A. CATTLE
Breed classifications:
- based on place of origin or adaptation
1. Bos indicus (Zebu breeds)
adapted to tropical conditions
has survived through centuries exposure to inadequate conditions such as food supplies, insect pests, parasites/diseases and weather extreme of tropical India.
2. Bos Taurus (European breeds)
adapted to temperate conditions
Characteristics of Zebu breeds as compared to temperate breeds:
1. large hump over top of shoulder and neck
2. large pendulous ears
3. dewlap having large amounts of excess skin
4. highly develop sweat glands (perspire more freely)
5. oily secretion from the sebaceous gland (believed to repel insect)
Based on the type of products:
- basically, cattle are kept to provide meat, milk and labor (draft animal power); beast of burden
1. Beef cattle – for meat
2. Dairy cattle – for milk
Breed – is a group of animals having common origin and possessing certain distinguishing characteristics which set them apart from other groups.
Zebu breeds Origin
Brahman US
Indu-brazil Brazil
Kankref India
Krishna India
Nellore Brazil
Red Sindhi Pakistan
Sahiwal India
Sta. Gertrudis US
Tharparkar India
Temperate breeds Origin
Angus Scotland
Chianina Italy
Simmental Switzerland
Ayrshire Scotland
Brown Swiss Switzerland
Guernsey France
Holstein-Friesian Netherlands
Jersey France
Breeding management:
- manipulative skills involved in producing the desired type of animals.
Breeding – art and science of genetic improvement
attained through proper mating of selected animals
Selection – process in which some individuals are chosen over as parents of the next generation
basis of selection; individual possessing desired traits and characteristics
1. Beef cattle – calf crop, rate of gain (ADG), carcass quality grade, FCE, etc.
2. Dairy cattle – milk yield, milk fat yield, FCE, etc.
System of breeding:
1. Inbreeding – is the mating of relatives (with common ancestor within the first 4 generations)
results in increased homozygosity (the state in which an animal has more uniform offspring because their chromosomes tend to be more alike)
a. linebreeding – is an inbreeding practice whereby several lines of pedigree are bred back to certain individuals
retains the favorable genetic traits of an ancestor to its offspring
2. Outbreeding – is the breeding/mating of unrelated individuals (heterozygosity or less uniform offspring)
offers opportunity to combine better genes through selection
a. crossbreeding – mating of individuals from two distinct breeds; crossbred is the resulting offspring
b. upgrading – mating of an animal from an unrecognized breed with a distinct breed; grade or upgrade is the resulting offspring
Breeding methods:
1. Natural method
- conventional use of bull to impregnate a heifer or cow
a. hand mating – a bull in good condition can serve 3-4 times/week or one service every other day
18 months old - 1:12-15
2 years old - 1:20-25
3 years old - 1:40-50
b. pasture mating (2-3 months)
2-3 year old bull - 10-15 cows
9 years old bull - 20-25 cows
2. Artificial insemination – process of inducing fertilization in female without the benefit of sexual contact between male and female animals
- involves collection of semen from bulls and artificially introducing it into the cow or heifers to achieve pregnancy
- requires detection of heat or estrus to determine when to inseminate
- requires detection of pregnancy to determine whether further insemination is needed
Outward physiological manifestation of in-heat animals (signs of estrus):
1. Reddening/swelling of vulva
2. Mucus discharges from vagina
3. Frequent urination
4. Restless and lack of appetite
5. Mounting other animals
6. Female stands still when mounted
Some basic parameters related to breeding management:
Parameters Goat Sheep Cattle
Weaning age (mos.) 3 3 6-8
Age at 1st estrus (mos.) 7-9 7-8 8-10
Estrous cycle (days) 18-24 15-19 18-24
Estrus (heat) period (hours) 24-72 18-24 8-30
Occurrence of estrus after parturition (post-partum) 2 months 17 days 3-8 weeks
Average length of gestation period (days) 150 150 283
Suitable age for breeding (months)
Male
Female
8
10
12
12
18
18-24
Male: Female (pasture mating) 1:20-25 1:20-25 1:10-25
Herd health management:
1. Hygiene and sanitation program
aimed at maintaining the contact of the animals with agents of infectious diseases or carriers/sources of these agents
hygienic measures:
- confine animals in suitable housing, whenever possible
- ample spaces or feeding, dinking, resting, clean house/disinfect; well-drained holding area
- proper disposal of dead animals
- check the drinking water supply (portable not contaminated with pathogenic microorganism)
- quarantine of premises during outbreaks of diseases
- regular grooming of animals
• to remove dirtstimulate the skins oil gland
2. Regular vaccination program
vaccination involves exposing an animal to an antigen derived from an infectious agent so that immune response is stimulated and the animal acquire to that infectious agent before natural infection occurs
groups of classic vaccines according to the status or bioactive agent included:
a. live antigen
b. killed (inactivated) antigen
- killed is for bacterial vaccines
- inactivated is for vaccines used against viruses or toxins
rendering immunity to animals against viruses or toxins
a. passive immunization – provides temporary resistance by transferring antibodies
e.g. colostral immunoglobulins
b. active immunization – is the result of natural infection or vaccination which involves the administration of antigen
some important disease in cattle
a. Foot and mouth disease (FMD) - Apthovirus types A, O, C
b. Hemorrhagic septicemia - Pasteurella multocida
c. Anthrax - Bacillus anthracis
d. Blackleg/malignant - Clostridium chauvei/septicum
e. Tetanus - Clostridium tetani
3. Regular parasitic control program
parasitism the most commonly encountered disease in the rural areas
- most important health problem considered by small farmers
type of parasites:
a. ectoparasites – found in the external surfaces of the animals body
b. endoparasites – inhabit the internal body organ (lungworms, liverflukes, kidney worms, intestinal worms)
Disease prevention procedures (biosecurity measures):
1. Quarantine measures
isolation of animals upon arrival
strict selection of animals free from diseases
usual symptoms of diseases:
a. fever
b. inappetence
c. coughing
d. sneezing
e. diarrhea
f. constipation
g. rapid breathing or thumping
h. recumbency
i. poor condition
j. rough hair coat
k. runting
l. abortion
2. Isolation of diseased animals
Feeding management:
ruminants (like cattle, carabao, goat, and sheep) can subsist on grasses and other fibrous feed materials
the compound stomach of ruminants enables it to utilize low quality feeds:
a. Rumen – fermentation vat; microbial degradation of ingesta
b. Reticulum – microbial degradation; aids in regurgitation
c. Omasum – further digestion
d. Abomasum – glandular (true) stomach
esophageal groove serve as passageway of milk in young ruminants to flow directly to the omasum bypassing the other compartments thus preventing microbial action
microbial action includes secretion of enzymes that converts carbohydrates and fiber in feeds to VFA (acetic acid, propionic acid, and butyric acid)
VFA the primary source of energy in ruminants
Groups of feeds for ruminants feeding:
1. Roughages – contain > 18 % CF e.g. grasses leaves of fodder trees like kakawate and ipil-ipil, rice straw, corn stover, etc.
2. Concentrates – contain < 18 % CF, high amount o digestible nutrients e.g. rice bran, copra meal, etc.
3. Feed additives and mineral supplements – added to improve feed utilization and balance the nutrients
shotgun treatment – giving of mineral mixtures to prevent deficiency
Ration – is the amount of feed provided to the animal in one day
Nutrient requirements – is the amount of nutrients required by the animal to meet the targeted production performance or output
Feeding strategy:
1. Confinement feeding (zero grazing) – cut and carry feeding system
lower energy expenditure for foraging
prevents trampling on high yielding pasture
lesser exposure to stresses imposed by weather changes, parasite infection
2. Tethering
practiced by small hold farmers
amount of feed intake is affected by the length of rope and frequency of tethering which is being dictated by the amount of available forage in the area.
3. Extensive grazing
animal freely forage feeds by itself in an area that may be enclosed by fences
Feed consumption capacity:
daily DM consumption ranges from 2.5 % of the body weight in mature animals to 3.0 % in younger or growing animals
in practical feeding, additional 10-15 % of the daily amount DM should be given to cover for animal feed preferences as not all the feeds will be consumed
feed wastage in the bran results trampling of the animal and contaminated with animals excreta. Animal will not consume such conditions of feeds
additional feed resources:
- leaves of leguminous fodder trees like ipil-ipil can supply up to 30 % of the total feed requirement. Legume leaves are good protein source which can replace the use of expensive protein feeds.
Housing:
the functions of animal shelter are as follows:
1. protection against climatic elements (rain, wind and temperature)
2. protection against losses due to theft, predators, infectious diseases and traumatic injuries
housing design must suit the desired performance and control of husbandry and breeding measures such as feeding, breeding and selection, reproductive events, rearing of the young and sanitation and hygiene.
in feedlot cattle production
- structure should be built with ample space foe efficient health maintenance and manure management
items to be included:
1. roofed, concrete floor squeeze for animal restraint
2. flow-through configuration to minimize distance to be traveled by the animal
3. durability of materials
other farm structures:
1. loading ramp
2. processing (routine operations: marketing, treatment deworming, spraying, etc.)
3. feeding pens
- floor space per animal 3-5 m2
- 1 side lined with feeding trough
• 0.45 m (18 in) elevated from the floor to trough bottom
• shallow trough floor (prevent feed decomposition)
• 0.45-0.6 m width
Manure management:
fresh manure
- about 5 % of a feedlot animals live weight
- which is 2x its 2.5 % DM daily ration
- contains 20-25 % DM, 75-80 % water
B. GOAT
Scientific name: Capra hircus
Some attributes:
1. Biological herbicide
2. Browsing ability (browser)
3. Diet: 40 % grasses and 60 % forbs (shrubs, herds)
4. bipedal stance
5. Ability to nibble barks of trees
6. Mobile lips (prehensile organ)
7. Walk long distances in search for food
8. Very selective in terms of feed preference (young shoot first is eaten)
Some breeds of goat in the country:
Breeds OriginAnglo-nubian England/USA
Saanen Switzerland
Alpine France/Switzerland
Toggenburg Switzerland
La Mancha Oregon/Spain
Boer South Africa
Native goat Philippines
C. SHEEP
Scientific name: Ovies aries
Some attributes:
1. Biological lawnmower
2. Essentially grazers
3. Flocking instinct
- pecking order, a social behavior related to hierarchy of dominance
4. Less selective of feed offered than goats
- can utilize rice straw
5. Feed preference and digestive efficiency
- comparable to cattle (commonly used to evaluate nutritive value of feeds intended or cattle)
- less efficient than goats and water buffaloes in utilizing highly fibrous roughages
Some breeds of sheep that has been brought into the country:
Breeds Origin
Barbados blackbelly Barabados Island with African ancestry
Priangan Indonesia
Shropshire England
Suffolk England
Merino Spain
Housing: floor space requirement (m2)
Category Zero grazing Day time grazing
Breeding females 1.5 0.8
Breeding bucks 2.0 1.5
Young stock (up to 1 yr old) 0.8 0.5
The estimation of the floor area of the goat house should be based on the number of breeding females with consideration o some of its parameters. This includes conception rate at 80 %; kidding interval of 8 months (or 1.5 kidding per year); an average kidding size of 1.5 kids per kidding; a disposal age of one year for grower animals; an annual replacement rate of 20 % for female breeders; and 80 % livability rate up to 1 year of age. However, the idea for possible expansion should be considered in the lay-out of the goat house.
e.g. 25 doe-level
1. Breeder females (does)
25 does x 1.5 m2 per doe = 37.5 m2
2. Breeder male (buck)
1 buck x 2.0 m2 per buck = 2 m2
3. Young stock
25 does x 80 % conception rate x 1.5 kids/kidding x 1.5 kidding/year x 80 % livability rate = 36 offspring/year x 0.8 m2 per animal = 28.8 m2
Total floor area = 68.3 m2
Total number of goats = 62 head
Feeding space – 0.4 m per animal
Floor elevation – 1.0-1.5 m above the ground (for ease of manure collection disposal)
Fencing is needed to effectively control the animals in the pasture
- goat = 1.5 m high (made of hog wire)
- sheep = 1.0 m high (made of hog wire)
- cattle = 1.0 m high (made of 3 strands of barbed wire)
Some infectious diseases of goats and sheep:
Disease Cause
1. Bacterial scours in kids Multiple bacterial agents (enteropathogen)
2. Bacterial pneumonia Multiple bacterial agents (pneumopathogens)
3. Infectious arthritis (big knee) Multiple bacterial agents acting singly or together (Erysipelorthrix, Corynebacterium, Chlamydia, Streptococcus, Staphylococcus, etc.)
Predisposing: dirty or unsanitary pens and areas of confinement
4. Mastitis Multiple bacterial causes with Streptococcus, Pasteurella, Corynebacteria and Escherichia most commonly noted. Also caused by Mycoplasma, Nochardia and Candida spp.
5. Contagious opthalmia or infectious kerato- Chlamydia and Mycoplasma spp.
conjunctivitis
6. Contagious ecthyma or sore mouth Virus
7. FMD (foot and mouth disease) Virus types identified in the Philippines: A, O, C
8. Foot rot Bacteria (Spherophorus necrophorus)
Predisposing: wounds in the feet, wet and muddy ground
9. Hemorrhagic septicemia Bacteria (Pasteurella multocida)
Predisposing: climatic stress, fatigue, transport, nutritional and parasitic stresses, etc.
10. Anthrax Bacteria (Bacillus anthracis)
11. Blackleg Bacteria (Clostridium chauvoei)
12. Tetanus Bacteria (Clostridium tetani)
Common parasitic diseases of goats and sheep:
Disease Cause
1. Parasitic gastroenteritis Various species of parasitic nematodes in the digestive tract. Young animals most susceptible.
2. Parasitic pneumonia Dictyocaulus spp. (adult stages in the bronchioles of lungs)
3. Tapeworm infection Moniesa spp.
4. Liver fluke infection Fasciola gigantica and F. hepatica. Requires intermediate hosts (Lymnea auriculata)
5. Coccidiosis Protozoa (Eimeria spp.) generally not a primary condition but exists with other enteric diseases
6. Cutaneous myasis or bowfly infestation Maggots of calliphorine lies (Lucilla, Calliphora and Chrysomia spp.)
Metabolic diseases of goats and sheep:
Disease Cause
1. Bloat Occurs under ordinary condition of management specially when feed lush herbage
2. Milk fever (hypocalcemia) Actual: deficiency of calcium in the bloodstream
Predisposing: grazing on young and rapidly growing forage, fasting or starvation in the last stages of pregnancy or during lactation, all forms of climatic and environmental stresses, heavy concentrate feeding without calcium supplement
3. Grass tetany (hypomagnesia) Actual: deficiency of magnesium in the bloodstream together with physiologic disturbances mostly neuromuscular arising from combined deficiency and steroid action.
Predisposing: lush pasture, over fertilization
of pasture with K and N or confinement and overfeeding with concentrate deficient in Mg or low in energy, pregnancy and lactation, sudden management or environmental stresses
4. Pregnancy toxemia (ketosis or acetonemia) Actual: acute glucose deficiency in the last stage of pregnancy due to twinning, large and rapid growing kid and sudden deficiency of feed
Predisposing: any sudden drop of intake attended stresses (starvation due to feed withdrawal/isolation without feed, transport climatic changes), also poor health, parasitism and other concomitant diseases
5. Urinary calculi Mostly associated with faulty mineral nutrition, confinement or concentrate feeding, inadequate water intake, vitamin A deficiency and infections of the urinary tract with Mycoplasma and Ureaplasma
6. Neonatal hypoglycemia Direct or actual: low glucose level in the blood
Predisposing: poor management at kidding time resulting to chilling, inability to suckle, prolonged delivery causing weak kids, injuries trauma, etc. may arise from individual unable to provide milk due to concurrent infection, low milk yield, or bad temper and other stressful conditions affecting dam and kid
7. Acute indigestion (lactic acidosis or grain Sudden dietary changes such as exposure and feeding of concentrates after prolonged high roughage diet
Some terms related to ruminant production:
Forage – edible parts of plants other than separated grain that can provide feed for grazing animals or that can be harvested for feeding.
Browse – leaf and twig growth of shrubs, woody vines, trees, cacti and other non-herbaceous vegetation available for animal consumption.
Forbs – any herbaceous broadleaf plant that is not a grass and is not grass-like (sedges).
Aftermath – forage grown following a harvest.
Sward – a population of herbaceous plants, characterized by a relatively short habit of growth and relatively continuous ground cover, including above and below-ground parts.
Animal unit – one mature non-lactating bovine weighing 350 kg (tropical condition) or 500 kg (temperate areas) and fed at a maintenance level, or the equivalent expressed as (weight) 0.75, in other kinds or classes o animals.
Daily dry matter intake or consumption – equal to 2.5-3.0 % of body weight.
Carrying capacity – the maximum stocking rate that will achieve a target level of animal performance, in a specified grazing method, that can be applied in over a defined time period without deterioration of the ecosystem.
Grazing pressure – the relationship between the number of animal units or forage intake units and the weight of forage drymatter per unit area at any one point in time; an animal to forage relationship.
Stocking density – the relationship between the number of animals and the specific unit of land being grazed at any one point.
Stocking rate – the relationship between the number of animals and the grazing management unit utilized over a specified time period.
Grazing cycle – the time elapsed between the beginning of one grazing period and the beginning of the next grazing period in the same paddock where the forage is regularly grazed and rested.
Grazing period – the length of times that grazing livestock or wildlife occupy a specific land area.
Alternate stocking – the repeated grazing and resting of forage using two paddocks in succession.
Continuous stocking – a method of grazing livestock on a specific unit of land where animals have unrestricted and uninterrupted access throughout the time period when grazing is allowed.
Deferred grazing – the deferred grazing in a non-systematic rotation with other and units.
Rotational stocking – a grazing method that utilizes recurring periods of grazing and rest among to or more paddocks in a grazing management unit throughout the period when grazing is allowed.
D. CARABAO/BUFFALO
What is the scientific name of?
1. Carabao – Bubalus bubalis carabanensis
2. Buffalo – Bubalus bubalis
3. Tamaraw – Bubalus mindorensis
Terminologies:
Carabao – Philippine water buffalo or swamp Carabao
Cara – prefix connected to the sex, class and meat of Carabao as introduced by Dr. Valente Villegas.
Carabeef – meat of Carabao
Carabull – breeding bull at any age
Caracow – mature female that already given birth
Caraheifer – female Carabao below 2 years of age and has not yet given birth
Chevron – two diagonal stripes on the ventral side of the neck, one near the brisket and the other near the jaw.
Draft animal – Carabao used for work
Silent heat – estrous behavior of Carabao wherein the animal is physiologically “in heat” but does not show any visible signs.
Wallow – to roll in mud or water
Yoke – a piece of arched or curved timber or wood fitted on the neck of draft Carabao.
Types of water buffalo:
1. Swamp type – Bubalus bubalis carabanensis, 2n = 48
breeds available are Philippine Carabao, Cambodian and Chinese buffaloes
light gray to gray, white bands below the jaw and across the chest and legs
sickle-shaped horns
1.5-2 kg of milk/day
2. River type – Bubalus bubalis, 2n = 50
breeds available are Indian and Bulgarian buffalo
black or dark gray in color
with tightly curled or drooping straight horn
dairy type buffalo can produce 8-10 liters of milk daily
Philippine Carabao Center (PCC):
created by virtue of RA 7307, otherwise known as the Philippine Carabao Act of 1992
an attached agency of the department of agriculture
became operational in 1993
signed into law by president Cory Aquino
main thrusts are:
- to develop the Philippine Carabao as source of milk, meat and raft through AI and natural mating.
- to conserve the Philippine Carabao
- to produce the best riverine buffalo for dairy
- RA 8485 or animal welfare act was signed into law in 1997 by President Fidel Ramos
- to protect and promote the welfare of all animals by supervising and, regulating the establishment and operations of all facilities utilized for breeding, maintaining, treating or training all animals.
- this law supersede the EO 626 or the Carabao slaughter ban
Breeding:
the Carabao can be bred throughout the year. Mating season usually takes place during the wet season.
high incidence of silent heat during dry season
estrous cycle is usually occurs every 21 days (range from 18-25 days)
estrus period (sexual receptivity) is 18 hours (range from 5-36 hours)
ovulation takes place, on the average, 15 hours after estrus
Gestation length and others:
gestation period is about 320 days (range 295 to 339 days)
age at first calving is about 3 to 4 years old
calving interval may range from 18 to 24 months
Crossbreeding program:
If the swamp buffalo is crossed with riverine buffalo, what will be the chromosome number of the offspring?
- all first generation offspring will have a chromosome number of 49
- inter se mating of F1 resulted to offspring F2 with 48, 49, and 50 chromosome numbers having 1:2:1 ratio
The unbalanced chromosome is due to the fusion of chromosome 4 and 9
- Are they fertile? Yes
Housing for feedlot fattening:
in an open confinement
- Mature feeders = 4 to 4.7 sq. m.
- Yearling = 2.8 to 3.7 sq. m.
Comparative composition of milk:
Composition Cattle Carabao
Water 87.28 80.16
Fat 3.80 8.60
Protein 3.30 5.20
Sugar 4.90 5.10
Mineral 0.72 0.94
Physical characteristics of meat:
Parameters Cattle Carabao
Muscle fiber diameter, micron
Semi-membranosus 60.28 54.28
Longissimus dorsi 58.16 53.47
Tenderness, lb/sq. in. 2.02 1.63
Firmness, mm 10.30 11.21
Water holding capacity, % 79.55 80.33
Acidity, pH 6.09 6.07
Sensory characteristics of meat:
Parameters Cattle Carabao
Color 4.77 4.58
Flavor 5.31 5.20
Off-flavor 1.28 1.22
Tenderness 5.00 4.62
Juiciness 5.19 5.13
General acceptability 5.54 5.13
What is Carabao slaughter ban?
EO 628 of 1990 locally known as 7-11 law; prohibits the slaughter of Carabao below 7 years old for male and 11 years old for female (also known as the Carabao slaughter ban)
How was it lifted?
RA 8485 of 1998 sec. 8 “Animal Welfare Act” this allows the slaughter of Carabao/buffaloes of any age provided the animal is not pregnant.
Unit 15: Swine Production
What is the scientific name of swine?
Sus scrofa / domesticus
Common breeds of swine in the Philippines:
1. The Philippine native pig
the native pigs are generally small and mostly solid black or black and white, with small ears, sway back, and with weak pasterns. They have good mothering ability, mostly prolific, and generally resistant to adverse conditions and adapted to local rural arm conditions.
2. Large white (Yorkshire)
large white is a white breed known for its good mothering ability and large litter size. The ears are medium-sized and carried erect. The snout is relatively short and straight and the legs are generally sturdy and strong. Some individuals in this breed are relatively short with big belly. They also tend to produce carcasses with thicker back fat.
3. Landrace
Landrace is also a white breed; some landrace have bluish-black spots/markings on the skin. This breed has a long body, large drooping ears, and long and relatively straight snout. It is also known for its mothering ability and prolificacy. The major defect o this breed is the weak hind legs and pasterns.
4. Duroc
this breed varies considerably in color of the skin and coat, which ranges from light golden brown o very dark red. Most duroc are cherry red. The head is small in proportion to the body, with medium-sized drooping ears and a snout that is relatively short and straight.
5. Pietrain
this breed is mostly spotted black and white, with medium-sized erect ears, although some individuals have slightly drooping ears, and moderately long a slightly dished snout. This breed is known for its good muscle development in the ham, loin, and shoulder with very thin backfat. The reproductive performance and mothering ability are relatively good and acceptable.
6. Hybrids
most hybrids introduced into the country do not have distinguishing physical characteristics, which may differentiate them from other breeds. Most of these hybrids, however, are white with good muscle development. Hybrid sows are claimed to be highly prolific; have better fertility; have bigger and more uniform litter; and have heavier piglets at birth. Slaughter hybrid pigs, on the other hand, are claimed to be outstanding in terms of growth rate, fed conversion efficiency, and carcass quality.
Some hybrid pigs available in the country are :
a. Hypor
b. New Dalland
c. Seghers
d. Camborough
e. JSR
f. Topigs
Definition of terms:
Boar – male pig of any age that is usually intended for breeding.
Colostrums – a yellowish milky fluid secreted by the mammary glands shortly before and a few days after farrowing.
Contamination – organisms is inside the pigs body without causing any clinical damage or disease.
Farrowing – act of giving birth in sows.
Gilt – young female pig less than one year of age and has not yet given birth.
Lesion – the disruptive changes in the organs/tissues of the animal when infected.
Litter – group of pigs born in one farrowing.
Litter size – the number of pigs born in one litter.
Pathogenic – the ability of the organism to cause damage or disease.
Sow – mature female pig, one that has given birth.
Suckling – young pigs, from birth up to weaning.
Terminal sire – a boar used in a crossbreeding program for the production of slaughter pigs, e.g., Duroc x Pietrain sires.
Triple cross pigs – pigs produced from the mating o a two-breed crossbred sow to a carefully terminal sire of different breed.
Weaning – the process of separating the young from its dam.
Weanling – young pig separated from the sow; about 30-90 days old.
Thursday, July 7, 2011
Poultry Production
Common name Scientific name Egg weight (g) Incubation period (days)
Chicken Gallus gallus Linn 58 21
Ducks
Mallard Anas platyrhynchos 60 28
Muscovy Cairina moschata 70 35-37
Turkey Meleagris gallopavo 85 28
Quail Coturnix coturnix japonica 12 16-18
Pigeon Columbia livia 17 18
Geese Cygnopsis cygnoides 200 30-31
Swan Olor columbianus 285 35
Ostrich Struthio austrialis 1400 42
Peafowl Pavo cristiatus 95 28
Pheasant Phasiannis colchicus 32 23-24
Guinea fowl Numida meleagris 40 28
Poultry – a collective term or all domestic birds rendering economic service to man. Domesticated animals are those than can live and multiply freely under the care of man.
Fowl – generally is a term applied to all poultry species specifically, applied to designate mature domestic cocks and hens. Poultry can refer also to the dressed carcass of fowls.
Poultry species – kinds of birds that are included in the term poultry (chicken, ducks, quail, turkeys, pigeons, geese, etc.)
Average live weight – average weight (in live form) of chicken during harvest/market age.
Beak – the projecting mouthpart of the chicken and turkey consisting of upper and lower mandibles; organs of prehension.
Bill – the projecting mouthpart of waterfowls, consisting of upper and lower mandibles.
Breeder – general term that designate the poultry raiser who produces fowls for any special purpose with the object of improving their value of in conformity with an agreed standard of excellence, the same term can be used to mean the animals used for breeding.
Breed – a race of domestic fowls which maintains distinctive characteristic shape, growth, and temperament and shell colors of eggs produced. Breed is a broader term than variety. Breed includes varieties, examples: Barred, White and Buff varieties of Plymouth Rock breed.
Broiler – meat type chicken commonly grown up to 35-42 days and weighing 1.5-2.0 kg live weight.
Brooder – a place where young chicks/ducklings are cared for after hatching until they have grown to a point where they no longer need additional heat.
Capon – caponized cockerels; usually grown up to 4 months and weigh up to 3 kg with more improved quality of meat.
Chicken – the most popular poultry species; different from turkeys, ducks, quails, geese, etc.
Chick – young domestic chicken while in the downy stage.
Clutches – group of eggs laid or successive days.
Cock/rooster – a male fowl one year old or over.
Cockerel – a male fowl less than one year old.
Comb – made of vascularized tissue growing on top of fowls head, this serves as an ornamental function, signs of status and condition of the male and for heat dissipation. The standard varieties of comb are single, rose, pea, V-shaped, strawberry, cushion and the buttercup; all other being modifications of these.
Crop – the receptacle in which the fowl’s food is accumulated before it passes through the gizzard.
Culls – old hens that had passed their usefulness or commercial egg production.
Debeaking – cutting part of the upper and lower mandibles with the use of electrically controlled cauterizing blade having a temperature of 815 0C to destroy the tissue responsible to generate beak growth, this is done to prevent cannibalism.
Down – the first covering of the chick whose major function is for insulation.
Drake – a male of the duck family.
Dubbing – cutting of the comb, wattles or earlobes so as to leave the head smooth.
Duckling – the young of the duck family in the downy stage of plumage.
Feed conversion ratio – volume of feed necessary to produce a kilogram gain in weight.
Hatching – the process where the fully developed embryo (chick) breaks out of the eggs.
Hatchery – a place where the facilities and process of incubation and hatching is done.
Harvest recovery – the number or volume of chicken sold/marked based on the number of day old chicks raised.
Incubation – period (in days) where embryonic development is takes place out of the body of the hen.
Layer – egg-type or dual-type 6 months old female that lays eggs.
Morbidity weight – number of chicken afflicted by disease.
Mortality rate – number of chicken that died based on the total number of chickens raised.
Oviposition – act o laying eggs.
Ovulation – mature ova released from the ovary which is affected by hormonal secretions (LH).
Plumage – the feathers of a fowl.
Poult – the young of a domestic turkey; the terms is properly applied until sex can be distinguished and when they are called cockerels and pullets.
Pullet – female fowl 5-6 months of age intended for egg production.
Pullet duck – a female duck less than 6 months old.
Primaries – the longest feather of a wing, growing between the pinions and secondaries, hidden when wing is folded, otherwise known as flight feathers.
Quill – the hollow, horny, basal part of stem of feather.
Secondaries – long, large quill feathers that grow between the first and second joints of the wing, nearest to the body, these are visible when the wing is folded.
Shank – the portion of a fowl’s leg below the hock, exclusive of the foot and toes.
Single comb – a comb consisting of a single, fleshy; serrated formation extending from the beak backward over the crown of the head.
Strain – a family of any variety of poultry that possess and reproduces with mark regularity, common individual characters which distinguish it from the families of the same variety.
Variety – a subdivision of a breed, a term used to distinguish fowls having the standard shape and other characteristics of the breed to which they belong but differing in colors of plumage, shape of combs, etc., from other groups of the same breed.
Wattle – the pendant growth at the sides and base of the beak.
Web of feet – the flat skin beside the toes.
Web – (web of feather) the flat portion of a feather, made up of a series of barbs on either side of the shaft.
Web of wings – the triangular skin attaching he three joints of the wings, visible when the wing is extended.
Chicken Gallus gallus Linn 58 21
Ducks
Mallard Anas platyrhynchos 60 28
Muscovy Cairina moschata 70 35-37
Turkey Meleagris gallopavo 85 28
Quail Coturnix coturnix japonica 12 16-18
Pigeon Columbia livia 17 18
Geese Cygnopsis cygnoides 200 30-31
Swan Olor columbianus 285 35
Ostrich Struthio austrialis 1400 42
Peafowl Pavo cristiatus 95 28
Pheasant Phasiannis colchicus 32 23-24
Guinea fowl Numida meleagris 40 28
Poultry – a collective term or all domestic birds rendering economic service to man. Domesticated animals are those than can live and multiply freely under the care of man.
Fowl – generally is a term applied to all poultry species specifically, applied to designate mature domestic cocks and hens. Poultry can refer also to the dressed carcass of fowls.
Poultry species – kinds of birds that are included in the term poultry (chicken, ducks, quail, turkeys, pigeons, geese, etc.)
Average live weight – average weight (in live form) of chicken during harvest/market age.
Beak – the projecting mouthpart of the chicken and turkey consisting of upper and lower mandibles; organs of prehension.
Bill – the projecting mouthpart of waterfowls, consisting of upper and lower mandibles.
Breeder – general term that designate the poultry raiser who produces fowls for any special purpose with the object of improving their value of in conformity with an agreed standard of excellence, the same term can be used to mean the animals used for breeding.
Breed – a race of domestic fowls which maintains distinctive characteristic shape, growth, and temperament and shell colors of eggs produced. Breed is a broader term than variety. Breed includes varieties, examples: Barred, White and Buff varieties of Plymouth Rock breed.
Broiler – meat type chicken commonly grown up to 35-42 days and weighing 1.5-2.0 kg live weight.
Brooder – a place where young chicks/ducklings are cared for after hatching until they have grown to a point where they no longer need additional heat.
Capon – caponized cockerels; usually grown up to 4 months and weigh up to 3 kg with more improved quality of meat.
Chicken – the most popular poultry species; different from turkeys, ducks, quails, geese, etc.
Chick – young domestic chicken while in the downy stage.
Clutches – group of eggs laid or successive days.
Cock/rooster – a male fowl one year old or over.
Cockerel – a male fowl less than one year old.
Comb – made of vascularized tissue growing on top of fowls head, this serves as an ornamental function, signs of status and condition of the male and for heat dissipation. The standard varieties of comb are single, rose, pea, V-shaped, strawberry, cushion and the buttercup; all other being modifications of these.
Crop – the receptacle in which the fowl’s food is accumulated before it passes through the gizzard.
Culls – old hens that had passed their usefulness or commercial egg production.
Debeaking – cutting part of the upper and lower mandibles with the use of electrically controlled cauterizing blade having a temperature of 815 0C to destroy the tissue responsible to generate beak growth, this is done to prevent cannibalism.
Down – the first covering of the chick whose major function is for insulation.
Drake – a male of the duck family.
Dubbing – cutting of the comb, wattles or earlobes so as to leave the head smooth.
Duckling – the young of the duck family in the downy stage of plumage.
Feed conversion ratio – volume of feed necessary to produce a kilogram gain in weight.
Hatching – the process where the fully developed embryo (chick) breaks out of the eggs.
Hatchery – a place where the facilities and process of incubation and hatching is done.
Harvest recovery – the number or volume of chicken sold/marked based on the number of day old chicks raised.
Incubation – period (in days) where embryonic development is takes place out of the body of the hen.
Layer – egg-type or dual-type 6 months old female that lays eggs.
Morbidity weight – number of chicken afflicted by disease.
Mortality rate – number of chicken that died based on the total number of chickens raised.
Oviposition – act o laying eggs.
Ovulation – mature ova released from the ovary which is affected by hormonal secretions (LH).
Plumage – the feathers of a fowl.
Poult – the young of a domestic turkey; the terms is properly applied until sex can be distinguished and when they are called cockerels and pullets.
Pullet – female fowl 5-6 months of age intended for egg production.
Pullet duck – a female duck less than 6 months old.
Primaries – the longest feather of a wing, growing between the pinions and secondaries, hidden when wing is folded, otherwise known as flight feathers.
Quill – the hollow, horny, basal part of stem of feather.
Secondaries – long, large quill feathers that grow between the first and second joints of the wing, nearest to the body, these are visible when the wing is folded.
Shank – the portion of a fowl’s leg below the hock, exclusive of the foot and toes.
Single comb – a comb consisting of a single, fleshy; serrated formation extending from the beak backward over the crown of the head.
Strain – a family of any variety of poultry that possess and reproduces with mark regularity, common individual characters which distinguish it from the families of the same variety.
Variety – a subdivision of a breed, a term used to distinguish fowls having the standard shape and other characteristics of the breed to which they belong but differing in colors of plumage, shape of combs, etc., from other groups of the same breed.
Wattle – the pendant growth at the sides and base of the beak.
Web of feet – the flat skin beside the toes.
Web – (web of feather) the flat portion of a feather, made up of a series of barbs on either side of the shaft.
Web of wings – the triangular skin attaching he three joints of the wings, visible when the wing is extended.
Genetics and livestock improvement
Additive effect – the effect of each allele in the locus where no interaction exists.
Chromosome number – diploid (2n) complement.
- haploid (n) complement
- composed of autosomes and sex chromosomes
Cloning – process of replicating an individual out of its own body cells.
Charles Darwin – proposed the theory of evolution in his book “The Origin of Species” in 1859.
Evolution – the long process of change in the characteristics of organisms that result into new species.
Genetics – the study of the nature and function of genes.
Genetic parameters – heritability, repeatability, covariance, correlation
Gene frequency – the proportion of a particular gene at a given locus.
Generation interval – average age of parents when offspring are born.
Genotypic frequency – the proportion of a particular phenotype present in the population or a breeding group.
Gregor Mendel – an Austrian monk who founded genetics through his studies on crossbreeding of garden Peas in 1865.
Heritability – the degree by which a character is genetically transmitted from a parent to offspring.
Hugo de Vries, Carl Correns, and Erik von Tschermark (1901) – independently rediscovered the works of Mendel that the modern concept of inheritance started to be understood and accepted.
Jay Lush – American scientist who introduced the application of the various theories of the genetics of population to the practice of animal breeding.
Mendelian traits – governed by few pairs of genes.
1. qualitative
2. discreet classes
3. independent segregation
4. independent assortment
5. coat/plumage color
6. presence/absence of horns
Outbreeding – mating of individuals closely related than the average of the population. Other form includes crossbreeding, upgrading, topcrossing, interspecific (between species) and intraspecific (within species).
Recessive – the state where the expression of a gene is suppressed by it alternative allelic gene.
Response to selection - function of heritability and selection differential.
Ronald Fisher – British scientist responsible for the integration of the concept of Darwinian evolution and Mendelian inheritance into the discipline of population genetics.
Selection differential – is the difference between the mean of the selected parents and the mean of the base population.
Selection methods – based on records of individuals and/or relatives.
Selection procedures for simultaneous trait improvement
1. Tandem
2. Independent culling level
3. Index selection
Sewall Wright – American biologist who contributed significantly to the integration of evolutionary and genetic theories into the study of population genetics.
William Bateson – English biologist who found in 1906 that Mendelian inheritance applied to animals (chicken).
Wilhelm Johannsen (1909) – a Danish biologist who coined the term “gene” to refer to the particulate factor that Mendel hypothesized as the basic unit of inheritance.
Genes and their functions
Francis Crick proposed the biochemical nature of the genes together with James Watson in 1950.
Gene – carrier of hereditary characteristics.
a segment of the DNA (abbreviation of deoxyribonucleic acid, a biochemical substance that bear the genes) that determines the base sequence of the nucleotide in the mRNA (acronym for messenger mRNA the biochemical substance that transcribes the genetic code in the process of protein synthesis) that makes up the code for a certain biological function
occurs in pairs
coined by Johannsen
helical structure by Crick and Watson
located in the chromosomes
located in the sex chromosomes
The DNA is a biochemical compound consisting of a chain of nucleotides called polynucleotide. Each nucleotide consists of phosphate (P), a sugar (S), and a base (B). The coding system of the gene is based on the arrangement of the four bases, namely; guanine (G), adenine (A), thymine (T), and cytosine (C).
Functions of genes
1. copy and replicate itself
2. store and transmit genetic information
3. undergo mutation
The manner by which the genetic information is transmitted from cell to cell is made possible through somatic cell division (mitosis). The transmission of the genetic material from parent to offspring is made possible through the reduction division of the germinal cells (meiosis) and subsequent union of gametes (the collective term for the reproductive cells from either the male or female).
The DNA segment consists of two strands of the chain of bases. These two strands arte linked together at each of the base so that it forms a helical shape or a twisted ladder. The nature of the gene is such that each base in one strand can only pair with a specific base. Thus, adenine (A) could only pair with thymine (T) and guanine (G) could only pair with cytosine (C).
In spite of the consistency and the precision by which gene copies itself, mistakes, even if they are rare, occur. These mistakes are copied and become incorporated as part of the genetic information itself. Such mistakes are called mutations. If the mutation occurs in the somatic cell, then it is transmitted only from cell to cell in the same individual. But if it occurs in the germinal cell, then it may be transmitted to the next generation.
Genes provides the code for the synthesis of proteins through a process of transcription (process whereby the sequence of the bases in the DNA is transcribed by the mRNA in the nucleus for subsequent translation into the corresponding protein material) and translation (process of synthesis of the polypeptide chain based on the base sequence in the mRNA) involving the RNA and the ribosome in the cell.
The role of genotype and environment on the phenotypic
Genotype – the specific combination of genes in the diploid phase representing a phenotype. It is assemblage of gene in an individual.
- determined at the time of fertilization
- genetic make-up
- genetic constitution
Environment – the external factor, other than the genes that affects the character of an individual.
- non-genetic factor
- modifies phenotypic expression
- nutrition, climate, management, season, housing, etc.
Phenotype – the observable effect of a gene action. It is a function of gene and environment.
- outward manifestation of a genotype
- traits
- characteristics
- measurable
- expressed at different stages in life
- same as genotype if effect of environment is zero
- qualitative or quantitative
- production, reproduction and adaptation
- economically important or not
The G x E may be defined as the interaction between the genotype of the individual and the environment under which it is raised. The effect of Genotype x environment interaction when certain genotypes perform well under certain environments than other genotype, e.g. the Zebu (humped) cattle grow and reproduce better in arm tropical environment than the European (humpless) cattle.
Gene action
Genes may be active only when they occur in pairs of alleles during the diploid phase.
Allelic genes – genes that occupy the same locus (the specific location of a pair of genes in the chromosomes) in the chromosome (the colored bodies in the nucleus that contain the DNA).
Genes perform different roles. There are the structural genes which are directly responsible for the synthesis of certain biochemical products during cell metabolism and there are also the regulator genes which serve to control or regulate the function of other genes. Regulator genes may function in terms of quantity, quality or timing of the activity of certain structural genes.
Action of genes may be detected only from the phenotype. The action of genes as they influence genotypic values may be any or a combination of the following types:
a. Partial dominance or incomplete dominance – when a pair of allelic genes contribute independently to the genotypic value, the action of the gene is said to be additive. It is intra-allelic interactions.
- example:
when a red (NN) cattle is mated to a white (nn) one the progeny is roan (Nn)
b. Complete dominance – when a gene suppresses the expression of its allele, the former is called the dominant gene while the later is referred to as the recessive gene. It is intra-allelic interactions.
- example:
when homozygous pea comb (genotype PP) and a single comb (genotype pp) are crossed, the progeny will be heterozygous pea comb (genotype Pp)
c. Epistasis – from the Greek word which means “to stand upon”. It is a type of genetic interaction where a gene in one locus suppresses the action of a gene in another locus.
- example:
in chickens, the presence of a dominant gene C at the C-c locus and the dominant gene O at the O-o locus enables the individual to synthesize the color pigment for its feathers. But in the presence of a dominant I gene at the I-i locus, the action of C and O genes in inhibited.
The mechanics of inheritance
1. Gametogenesis and fertilization
- gametogenesis, the process of production of gametes
a. spermatogenesis – process of producing sperm cells
b. oogenesis - process of production of female gametes
- fertilization, the process of introduction of the sperm cell into the egg to form a zygote
2. The Mendelian inheritance
- laws of inheritance:
a. Laws of segregation – characters are determined by particulate factors (later given the term genes) and that these factors occur in pairs. In the formation of gametes, these factors are segregated so that only one of the pair is transmitted by a particular gamete.
b. Laws of independence – in the formation of gametes, members of one pair of genes segregate independently of other pairs.
3. Non-mendelian inheritance
- governed by many pairs of genes interacting with one another:
a. Sex-linkage – the state where a gene is located in the sex chromosomes
- mammals: XY-male; XX-female
- birds: ZZ-male; ZW-female
- homogametic, the sex that carries identical sex chromosomes, e.g. X and X in mammals
- heterogametic, the sex that carries the different sex chromosomes, e.g. X and Y in mammals
- there are known to be sex-linked, these include hemophilia and color blindness, barring plumage pattern and dwarfism
b. Autosomal linkage – state when the genes are located in the same autosome (the type of chromosome other than the sex chromosome)
- parental type of gametes, those that were similar to what the offspring received from the parents
- recombinant type of gametes, those that are different from what was received from either of the parents but were produced as a result of crossing over of chromosomes during meiosis
- test-crossing, crossing of an individual of unknown genotype
c. Non-nuclear inheritance – in this case, the females would play a larger role than the male in influencing the characteristics of the progeny since the sperm cells have very little, if any, cytoplasmic material
d. Quantitative traits
e. Continuous distribution
f. Sex-influenced
Maternal influence – the mother could further influence the characteristics of her offspring because of the maternal care she provides to her young.
Genes in Populations
- populations, a group of individual sharing a common gene pool
- gene pool, is the totality of the genes that could potentially be transmitted by individuals in a populations to the next generation
1. Genetic composition of animal population
-populations are characterized by the frequencies in which the genes and genotypes occur in them
2. Equilibrium population – a population in which the genes and genotypic frequencies do not change generation after generation
- Hardy-Weinberg Law, gene and genotypic frequency remain constant from generation to generation if population is large, there is random mating and there is absence or if there is balance of selection, migration and mutation. Hardy (British mathematician) and Weinberg (German physician) independently formulated the principle in 1908
- violation in Hardy-Weinberg equilibrium:
a. small population leads to genetic drift
b. assortative or dissortative mating
c. natural or artificial selection
d. movement of animals through importation of live animals, semen or embryo
e. change in biochemical structure of genes
3. Factors affecting change in the genetic composition of populations
a. Selection – process where certain individuals are able to contribute more progeny in the next generation than other individuals
- natural selection, natural forces
- artificial selection, intervention of man
b. Migration – process of movement of individuals from one population to another population
c. Mutation – spontaneous change in the biochemical or structural characteristics in the genetic material that results in a different biological action
d. Small population size
e. Non-random mating – occurs when some individuals do not have the same chances of mating with individuals of the opposite sex
- forms of non-random mating:
Assortative mating – individuals that are more phenotypically similar tend to mate more often
Disassortative mating – individuals which are less phenotypically similar tend to mate more often together than would be expected by chance
Inbreeding
Unit 7: Animal Breeding
- the art and science of genetic improvement of farm animals
1. Objectives of animal breeding
a. improve the quantity of production
b. improve the efficiency of production
c. improve the quality of farm animals
d. improve the aesthetic value of farm animals
2. Systems of animal breeding
a. Selection
b. Inbreeding – the process of mating animals that are closely related by descent
- increase genetic homozygosity
- inbreeding depression
- lowly heritable traits
- closest possible inbreeding animals is full-sib mating and parent-offspring mating
- inbreeding may be achieved by:
irregular systems, the relationship between mates in the pedigree is vary
regular systems, the relationship between mates is constant throughout the generations
c. Crossbreeding – the breeding of individuals from one population to individuals from another distinctly different population
- hybrid vigor or heterosis, a condition where the heterozygote is better than the average of the homozygote
F1 progeny is better than the average of the parents
Better than the average of the better parent
Occurring on lowly heritable traits
Caused by non-additive gene action (dominance, epistasis) higher than in the F1 than in the F2
Unit 8: Reproduction
- reproductive cycle and rate of genetic improvement
- frequency of ovulation and length of embryonic development:
Artificial insemination – techniques of introducing semen into the oviduct without the benefit of the male
- effective if the superior animal is the male
- benefit derived from artificial insemination:
a. the number of female that could be mated by a single male is increased dramatically
b. STD are minimized
c. male that are physically unable to mate naturally may still be used fro breeding
d. semen of bulls that have been long dead may still be used for inseminating cows
e. because the number of progeny that could be produced by a single male is increased the accuracy of evaluating the breeding value of a male is increased proportionately
Multiple ovulation and embryo transfer (MOET) – a process of hastening the reproductive rate of female animals
- effective if the superior animal is the female
- multiple ovulation, process by which the female animal is induced to simultaneously ovulate more eggs than what is normally shed
- embryo transfer, technique wherein a young embryo is collected from a donor female parent and then implanted into the uterus of a recipient female parent
Sexing semen – separating the fraction of the semen that would carry a much larger proportion of sperm cells carrying the Y-chromosomes than those that carry the X-chromosomes.
In vitro fertilization – experimentally induced biological processes outside the organisms.
Nuclear cloning – continued splitting of embryos that would lead to an indefinite duplication of an individual
Definition of terms
Meat terms:
Meat – the carcass or carcass parts coming from animals sufficiently mature and healthy
Beef – meat from cattle more than one year old
Veal – meat from cattle less than one year old
Carabeef – meat from carabao more than one year old
Chevon – meat from goats
Pork – meat from swine
Mutton – meat from sheep
Lamb – meat from lambs
Venison – meat from deers
Hot meat – meat coming from an illegal source
Fresh meat – meat that has not undergone any substantial physical, chemical and microbiological changes from the time of slaughter
Meat by-products – the edible by-products from the slaughterhouse
Abattoir – the premises approved and registered as premises for slaughtering animals for human food
Cold slaughter – slaughtering an animal dead of some causes prior to slaughter
Fabrication – process of cutting carcasses into standard wholesale and retail cuts
Flaying – a ct of removing hide from animals
Corned meat – prepared meat cured by soaking with or without one or more of nitrate, nitrite, sugar dextrose, syrup, honey and with or without the use of spices
Curing – the addition of salt with or without nitrite, nitrate and sugar for the purpose of lengthening shelf life and/or enhancing the development of odor, color, and flavor
Quick freezing – freezing products at a temperature of -20 °F or lower
Green hams – unsmoked cured hams
Hot boned meat – meat deboned before the development of rigor mortis
Milk terms:
Pasteurization – it is a process of heating a foodstuff, usually liquid, for a definite time at a definite temperature and thereafter cooling it immediately. US public health service recommends heating milk to at least 145 °F for at least 15 seconds
Homogenization – fat globules are subjected to mechanical treatment, which breaks them down into smaller globules, uniformly dispersed in the milk
Certified milk – fresh milk of higher purity to be delivered to the customer within 36 hours. The number of bacteria is 10,000 or less per ml
Pasteurized milk – milk heated to a temperature of not lower than 145 °F for a period of not less than 30 minutes
Homogenized milk – milk than contains finer globules of butterfat than those present in fresh milk. It is prepared by passing fresh milk through small openings by pressure.
Evaporated milk – fresh milk which has been evaporated to a concentration of 73.7 % water. It contains 7 % protein, 7.9 % fat, 9.9 % lactose and 1 % minerals
Condensed milk – concentrated milk to which sugar has been added. It has 27 % water, 8.1 % protein, 54.8 % lactose and 1.7 % minerals
Filled milk – milk where the butterfat is replaced with vegetable fat such as coconut fat
Dried or powdered milk – dried milk obtained by evaporating the moisture from the milk solids
Recombined milk – dry skim milk, dry buttermilk plus butter oil
Reconstituted milk – milk powder plus water
Basic principles of selecting animals prior for slaughter
- the basic considerations in selecting animals are as follows:
a. sex consideration
b. age consideration
c. size consideration
d. class considerations
e. health consideration
f. finish considerations
Management of Animals Prior to Slaughter
There are four management practices given to animals prior to slaughter. These are fasting, allowing animals to relax, handling them gently and keeping them as clean as possible.
Fasting
Feed is not given to the animal, however, sufficient amount of water is provided. Simple stomach animals are fasted for 12 to 24 hours whereas the ruminants are fasted for 24 to 48 hours. Advantages of fasting include savings of feeds, ease of cleaning entrails and eviscerating carcasses, thoroughly bled and brightly colored carcass, long shelf life and low shrinkage of resulting meat.
Relaxed animal
No form of stress should be given to animal prior to slaughter. If stress cannot be avoided, animals must be given enough time to rest and gain their composure before they are slaughtered. One to three-day relaxation in the holding pen is enough to remove the effects of stress on the animal depending on the degree of stress.
The disadvantages of stress include loss of muscle glycogen, high temperature of carcass, low water holding/binding capacity of resulting meat, low aroma, flavor, texture and juiciness scores.
Handling animal gently
The part of an animal whipped, kicked or boxed prior to slaughter develops blood clots and red spots in the meat. Blood clots in meat are support for luxuriant growth of microorganisms and cause accelerated meat spoilage.
Clean animal
Good sanitation practice is best started by keeping the animal clean. One of the worst contaminants of meat is the micro flora abundant in feces.
Basic requirements in slaughtering animals
Basic factors to consider in slaughtering:
1. cleanliness of meat produced
2. hygiene or production
3. efficiency of meat inspection
4. adequacy of meat preservation
The slaughterhouse:
1. There must be complete facilities for the proper care of animals prior to slaughter.
2. The slaughterhouse should have separate rooms for the slaughter of swine and ruminants.
3. The slaughterhouse must have good drainage and ventilation, must be at least 100 meters away from residential houses and must have adequate pollution control device.
Classification of slaughterhouse in the Philippines:
1. AAA – those with facilities and operational procedures so adequate that the meat processed herein is eligible for sale in any market in and out of the country.
2. AA – those with facilities and operational procedures sufficiently adequate that the meat processed herein is eligible for sale in any market in the Philippines.
3. A – those with facilities and operational procedures of minimum adequacy as defined by the National Meat Inspection Commission (NMIC), the meat processes herein is eligible for sale only in the city or municipality in which the plant is located.
4. Non-accredited – those with facilities and operational procedures of less than minimum standards that must be closed until minimum standards are provided or achieved.
Slaughtering animals
1. Ante-mortem inspection – is determining whether an animal is fit for slaughter or not.
2. Stunning – is making animals unconscious but not killing them.
3. Sticking – animals must be stuck within 3 minutes after stunning.
4. Cleaning of the carcass – vary within species. There are three distinct methods of cleaning carcasses:
a. Flaying – is removing the hide. This is commonly done in carabaos, cattle, horses and goats.
b. Scalding – is submerging the carcass in hot water to loosen the hairs and scurf. Scalding is necessarily followed by scraping. The temperature of scalding water must be controlled at 130-180 °F.
c. Singering - is burning the hairs and scraping the hairs as soon as these are burned. This is commonly done in goats.
5. Evisceration – starts from the time cuts to open the carcasses are made and end when the slaughter by-products are removed from the body cavity.
6. Splitting/washing – splitting is cutting the carcass into two equal parts. The carcass must be splitted at the backbone, but the tail normally goes with the left side if it is not removed before cutting. Right after splitting the carcass is washed very thoroughly and the parts with blood clots are trimmed.
7. Post-mortem inspection – this is inspecting the carcass for final determination whether it is fit for human consumption or not.
8. Shrouding – is wrapping the carcass with cheesecloth.
9. Chilling – the chilling room where carcasses are laced after slaughter should have a temperature of 0-4 °C (32-40 °F).
10. Aging – is holding the meat for 7-14 days at 36 °F to improve tenderness and flavor of meat.
Meat fabrication
Fabrication is cutting carcasses into standard wholesale and retail cuts.
Four principles to follow in cutting carcasses:
1. thick portions must be separated from the thin ones
2. the tender parts must be separated from the less tender portions
3. the high priced cuts are separated from the less expensive parts
4. cuts must be made across the muscle fibers
Dressing yield of common livestock and poultry:
Dressing % = carcass weight / slaughter x 100
- obtained after 24-48 hours chilling without the head and internal organs
Lean-fat-bone yield = component / live weight x 100
Boneless recovery = boneless carcass / live weight x 100
Unit 10: Composition of Meat, Milk and Eggs
The meat
General characteristics
1. Meat is a high quality, concentrated and easily digested source of nutrients and is well balanced with regard to the relative amounts of specific nutrients which it contains. It is an excellent source of high quality protein, B-complex vitamins and of certain minerals.
2. Meat provides satiety unequaled by other food items, it can be prepared in several ways and it provides nutrients almost in the proportion and amount needed by the human body. Because of its high nutritive content, microorganisms also love to attack it, hence spoils fast at ordinary room temperature.
Physical component of meat
a. The basic structures that can be seen in meat are lean, fat, bone, skin, connective tissues, and blood vessels. Some meat cuts have also noticeable bone marrow inside the bones.
b. The lean or muscle is considered the most important among the components because of its palatability and nutritive value. Muscle also comprises the bulk of the carcass (about 50-65 %).
c. The fat tissues are the most variable constituents of meat. The amount of fat in the body is markedly influenced by the diet, age, exercise and other physiological factors.
d. The amount of connective tissues is also important in meat because it determines the tenderness or toughness of the meat. The higher the amount of connective tissues, the tougher the meat is.
Chemical composition of meat
- The chemical composition of meat is usually presented by its proximate composition. The proximate composition of meat varies depending on:
1. species from which the meat was obtained
2. degree of fatness to which the animal has been fed
3. specific cut used
4. extend of cutting and trimming
5. curing and processing treatment
Relationship of physical structure and chemical composition to the eating qualities of meat
1. kind of protein
2. amount of fat specifically marbling
3. carbohydrates
4. moisture content
5. nitrogenous extractives
6. connective tissues
7. muscle fibers bundle
Nutritional value of meat
1. connective tissues proteins have high amount of proline, hydroxyproline, and glycine and has low tryptophan and tyrosine
2. meat is an excellent source of the B vitamins, phosphorus and iron but relatively low in calcium. The cooking and processing of meats do not appreciably affect the quantity or availability of the mineral elements present as long when mineral salts are added.
The milk
General characteristics of milk
1. Milk ranges from a bluish white to almost golden yellow color. In large quantities, milk appears entirely opaque.
2. Milk has no pronounced taste but slightly sweet to most persons. Freshly drawn milk has low characteristics odor but gets lost upon exposure to air.
3. The pH of fresh milk is about 6.5. When milk is allowed to stand undisturbed for a few hours, a layer forms on the surface. This layer is the cream which is composed of fat globules.
4. Since milk is very nutritious, microorganisms grow in it very fast and spoil it. The normal freezing point is -0.545 °C.
Chemical composition of milk
1. Water is the principal constituents of milk. It is about 78-88 % (average of 87 %) of the fresh whole milk.
2. Fats are also present in the form of fat globules which amount to 3-10 % of milk. Fats are very good absorber of flavor and odor and usually come into two forms:
a. true fat (glycerides)
b. associated substances (lecithin, cholesterol, carotene, vit. A, D and E)
3. Carbohydrates in milk are in the form of lactose, which is about 4-5 % (average of 4.9 %) of the milk. Lactose is complex disaccharide made up of glucose and galactose. This is easily fermented by microorganisms to lactic acid.
4. Nitrogenous component of milk is made up of 95 % protein and 5 % non-protein. The milk has around 3-6 % protein. The 78.5 % of protein in milk is casein while 16.5 % rest is milk serum protein. The protein milk is considered as of high quality; almost the same as in meat, but a little bit lower than that of egg. Milk protein is slightly deficient is sulfur containing amino acid.
5. Milk has 0.7-1.0 % ash or inorganic minerals. Milk is a rich source of calcium, magnesium, phosphate and citrate.
The colostrums has 73.79 % water, 1.17 % protein, 6.74 % fat, 2.30 % lactose and 1.0 % ash while human has 87.6 % water, 1.2 % protein, 3.8 % fat, 7.0 % lactose and 0.4 % ash.
Nutritional value of milk
1. Milk contains broad distribution of nutrients. Milk is especially rich in high-quality protein, calcium, phosphorus, riboflavin, ands other B vitamins. It is poorer source of vitamin D, C, and iron.
2. Milk protein is one of the highest quality proteins. The only principal deficiency of milk protein is the sulfur containing amino acids: cystine and methionine. It is very rich in lysine. Milk lipids, however, contain high saturated fatty acids and low linoleic acid and linolenic fatty acid.
3. The fat-soluble vitamins of milk exist partially in a free state and partially bound to proteins. There, the biological activity of the bound forms may-depend on their release upon ingestion.
The egg
General characteristics
The egg is compact package of well-balanced food nutrients. Eggs have high protein, very low in carbohydrate, have high vitamin A, riboflavin and vitamin D. it is richest source of iron in animal foods. One chicken egg weighs on the average about 50-60 grams. Calcium is in the form of CaCO3.
Constituent of egg
The egg is basically composed of around 31 % yolk, 59 % albumen or white and 10 % shell. The yolk is made up of 47-48 % moisture, 16 % protein, 32-35 % ether extract or fat and around 1 % carbohydrate. The ether extract component of yolk contains phospholipids, triglycerides and cholesterol. On the other hand, the albumen is made up of 87-89 % moisture, 9.7-10.6 % protein, 0.5-0.6 % ash, 0.03 % fat and 0.5-0.9 % carbohydrates.
Common tests to determine composition of meat, milk and egg:
Composition Laboratory Analyses
Meat Milk Egg
Moisture Oven drying Oven drying /use of lactometer Oven drying
Total solids Oven drying Use of lactometer Oven drying
Ash Ignition Ignition Ignition
Crude fat Ether extraction /Babcock test Ether extraction Babcock test
CP Kjeldahl analysis Kjeldahl analysis Kjeldahl analysis
Casein N/A Walker method N/A
Measures of egg quality:
1. Whole egg characteristics
• Size, shape, color, texture, cleanliness, uniformity of eggs
• Floatation test
2. Candling characteristics
• shell, air cell, yolk, white and germ
• bubbly air cell – state, weak shell membrane, rough handling
• air cell moves – broken inner membrane
• normal yolk – faint shadow at the center of egg
• abnormal yolk – moves freely and casts darker shadow
• old egg – floats
• high quality egg has no germ development (blood begins to show after 48 hours at 100-103 °F)
3. Broken out odor, flavor, physical characteristics
• normal – yolk is well rounded
• old – flattered and spread out
• haugh unit – height of yolk – log of albumen
- height corrected to standard egg weight of 2.03
HU = 100 log {H – [G (30 W – 37 – 100) + /g] / 100}
HU – Haugh units
H – Albumen height
G – Gravitational constant
W – Weight of eggs
- simplified formula:
HU = 100 log (H + 7.57 – 1.7 W – 37)
4. Other measures of quality
• yolk index = measures of the standing up quality of yolk
= height of yolk / diameter
0.42 – 0.4 = normal
0.25 = low
Unit 11: Basic Principles of Proper Handling and Processing of Meat, Milk and Egg
Causes of deterioration
Categories:
1. Biological forces. Biological spoilages may also be brought about by flies, rodents and cockroaches. Spoilages of these kinds are however easy to control. Working in ideal rooms may entirely eliminate insect spoilage problems.
2. Chemical forces. Oxidation is a common chemical cause of meat, milk and egg deterioration. Oxidation of the fats causes rancidity while oxidation of the color pigment in meat causes darkening.
3. Physical forces. Dehydration and enzymatic action are two of the physical processes causing food deterioration. These two are expensive to minimize and very impractical to completely stop or control.
Processing of meat
Meat processing refers to any or combination of process utilized in altering fresh meat.
1. Cold storage may be divided into chilling and freezing.
a. Chilling is subjecting meat to a temperature of 32-40 0F (0-4 0C). There is rapid cooling but there is no hardening and freezing of meat juices.
b. Freezing of meat is either slow or quick freezing. The meat hardens in 30 minutes in quick freezing. Longer time is required in slow freezing. Quick freezing on the other hand can be accomplished by blast, deep, cryogenic, direct immersion, indirect immersion, indirect contact and spray freezing. Quick freezing is more advantageous than slow freezing because there is less destruction of the muscle fibers, less drip, minimal loss of water holding capacity and flavor of product.
2. Drying meat is lowering the available water in meat. This can be done by withdrawing the water by binding the water and renders it unavailable for microbial growth.
3. Salting is accomplished by the addition of salt, hypochlorite of calcium and/or other salts. Through osmosis, salts withdraw water from meat and causes plasmolysis of bacterial cells. Salts also ionize to yield chlorine ion, which is harmful to organisms. Other action of salts include reducing the availability of oxygen in the moisture, sensitizing bacterial cells to carbon dioxide, reducing the action of proteolytic enzymes and accelerating development of rancidity.
4. Canning is hermetically sealing of meat in a container and then subjecting it to thermal process. All the organisms present are killed in this process and the product is considered commercially sterile.
5. Curing started as a method of meat preservation; however, as time went by, people developed the liking for cured flavor. There are basic ingredients required in meat curing. These are salt, sugar, and nitrate/nitrite.
Ordinary table salt is the major portion of the curing ingredients. It inhibits the growth of putrefying bacteria, hardens muscle fibers and draws out moisture from the meat. Together with other ingredients, it adds desirable flavor and texture to the meat.
Sugar adds flavor, helps overcome saltiness and counteracts the toughening effect of salt. It is also utilized as media by some beneficial organisms.
Nitrate/nitrite helps develop cured color and flavor and inhibit microbial growth.
Quality in meat
The word quality infers superiority and degree of excellence
Measures used to evaluate quality in meat:
1. Lean color
- Bright colored meat gives so much appeal to the consumer
- Indicates how long a cut of meat has been held on meat stall
- Improves selling or marketability of meat
- Helps identify species of animals from which the meat is taken
2. Lean firmness
3. Lean texture
4. Marbling
5. Age or maturity of the carcasses
Milk processing
1. Straining – right after milking, the milk is strained using sterilized cheesecloth.
2. Cooling milk – the milk should be cooled to 50 0F of lower as soon as it is milked out to minimize microbial growth.
3. Clarification and filtration – this process is done to further remove dirt, which were not removed during straining. Clarification is the by the use of the principle of centrifugation, while filtration is using the principle of filter paper.
4. Separation – this is separating the cream and the skim milk. This can be accomplished by either gravity method or using a mechanical cream separator.
5. Pasteurization – treating milk with heat thereafter followed by rapid cooling to destroy bacteria. About 98.99 % of bacterial cells die. Pasteurization can be done by either:
a. Holding process – milk is heated to 145 0F (62. 8 0C) for 30 minutes, then cooled rapidly/.
b. Flash process:
- HTST (High temperature short time) – milk is heated at 165-185 0F (73.9-82.2 0C) for 15 seconds.
- UHT (Ultra high temperature) – milk is heated at 192-194 0F (80-90 0C) for 1 to 4 seconds.
6. Homogenization – forcing milk through small opening under high pressure. Normal pressure is from 2,500 – 5,000 psi. Fat particles are reduced to less than 2 microns in diameter.
Forms of milk in the market
1. Fresh whole milk
2. Whole milk powder – water is removed
3. Skim milk – fat or cream is removed
4. Skim milk powder (SKMP) – water is removed from the skim milk, also known as non-fat dry milk
5. Evaporated milk – some water removed
6. Condensed milk – more water removed plus water
7. Filled milk – SKMP = vegetable oil + Vitamin A and D
8. Homogenized – small fat globules (2,500-5,000 psi)
9. Flavored milk – SKMP + water + flavor
10. Whey powder
Unit 12: Marketing of Livestock and Livestock Products
Methods of marketing livestock in the Philippines
1. Livestock market/concentration yards - farmers or traders bring their animals to the concentration yards to sale. Markets usually have facilities for the care of animals. The transactions could be:
trader to trader;
farmer to trader; and
trader to farmer.
2. Barrio agents – perform one or both of the following:
buy livestock from scattered backyard farms and sell these to viajeros; and
act as a viajero or wholesaler and sell livestock, directly to retailers. These agents are highly skilled especially in live weight estimation.
3. Wholesalers or viajeros – buys livestock in wholesale quantity, transport the livestock and resell them to wholesalers, retailers and/or processors.
4. City dealers – are the intermediaries between the provincial viajeros and the wholesalers in the cities.
5. Retailers – are those who buy animals and sell them to consumers. These are very common in goat marketing.
6. Contract growing schemes – there are several approaches used in contact scheme. In all of the schemes, a mother company takes the animals produced and takes care of the processing before final sale to consumers.
Problems commonly encountered in the marketing of livestock
1. No grade standards
2. Lack of integrated information
3. Difficulty of transporting animals
4. Cost of transportation is very high
5. Lack of suitable public transport system
Meat and Meat Products Marketing
Traditionally, the meat distribution system is multi-layered with many middlemen involved in the whole process. The most common is the five (5) level distribution system.
Producer ------- Barrio agent ------- Wholesaler ------- Retailer -------- End consumer
However, recent trends indicate that more producers have resorted to direct marketing system in an effort to reduce or totally eliminate the middlemen involved and maximize profits.
Producers ----- retailers
• wet market
• institutional markets
- supermarkets
- groceries
- hotels
- restaurants
Types of meat markets
1. Retailers
a. Wet markets – are those meat stalls in public markets where meat are usually hung in bulk and sliced only when a customer comes. Wholesalers usually supply meats for these markets.
b. Supermarket style/meat shops – are components or grocery stores, supermarket or individual meat shops. Meats are properly fabricated and handled.
2. Wholesalers
a. pack trading
b. packers to retailers
c. retail outlets
d. institutional outlets
Chromosome number – diploid (2n) complement.
- haploid (n) complement
- composed of autosomes and sex chromosomes
Cloning – process of replicating an individual out of its own body cells.
Charles Darwin – proposed the theory of evolution in his book “The Origin of Species” in 1859.
Evolution – the long process of change in the characteristics of organisms that result into new species.
Genetics – the study of the nature and function of genes.
Genetic parameters – heritability, repeatability, covariance, correlation
Gene frequency – the proportion of a particular gene at a given locus.
Generation interval – average age of parents when offspring are born.
Genotypic frequency – the proportion of a particular phenotype present in the population or a breeding group.
Gregor Mendel – an Austrian monk who founded genetics through his studies on crossbreeding of garden Peas in 1865.
Heritability – the degree by which a character is genetically transmitted from a parent to offspring.
Hugo de Vries, Carl Correns, and Erik von Tschermark (1901) – independently rediscovered the works of Mendel that the modern concept of inheritance started to be understood and accepted.
Jay Lush – American scientist who introduced the application of the various theories of the genetics of population to the practice of animal breeding.
Mendelian traits – governed by few pairs of genes.
1. qualitative
2. discreet classes
3. independent segregation
4. independent assortment
5. coat/plumage color
6. presence/absence of horns
Outbreeding – mating of individuals closely related than the average of the population. Other form includes crossbreeding, upgrading, topcrossing, interspecific (between species) and intraspecific (within species).
Recessive – the state where the expression of a gene is suppressed by it alternative allelic gene.
Response to selection - function of heritability and selection differential.
Ronald Fisher – British scientist responsible for the integration of the concept of Darwinian evolution and Mendelian inheritance into the discipline of population genetics.
Selection differential – is the difference between the mean of the selected parents and the mean of the base population.
Selection methods – based on records of individuals and/or relatives.
Selection procedures for simultaneous trait improvement
1. Tandem
2. Independent culling level
3. Index selection
Sewall Wright – American biologist who contributed significantly to the integration of evolutionary and genetic theories into the study of population genetics.
William Bateson – English biologist who found in 1906 that Mendelian inheritance applied to animals (chicken).
Wilhelm Johannsen (1909) – a Danish biologist who coined the term “gene” to refer to the particulate factor that Mendel hypothesized as the basic unit of inheritance.
Genes and their functions
Francis Crick proposed the biochemical nature of the genes together with James Watson in 1950.
Gene – carrier of hereditary characteristics.
a segment of the DNA (abbreviation of deoxyribonucleic acid, a biochemical substance that bear the genes) that determines the base sequence of the nucleotide in the mRNA (acronym for messenger mRNA the biochemical substance that transcribes the genetic code in the process of protein synthesis) that makes up the code for a certain biological function
occurs in pairs
coined by Johannsen
helical structure by Crick and Watson
located in the chromosomes
located in the sex chromosomes
The DNA is a biochemical compound consisting of a chain of nucleotides called polynucleotide. Each nucleotide consists of phosphate (P), a sugar (S), and a base (B). The coding system of the gene is based on the arrangement of the four bases, namely; guanine (G), adenine (A), thymine (T), and cytosine (C).
Functions of genes
1. copy and replicate itself
2. store and transmit genetic information
3. undergo mutation
The manner by which the genetic information is transmitted from cell to cell is made possible through somatic cell division (mitosis). The transmission of the genetic material from parent to offspring is made possible through the reduction division of the germinal cells (meiosis) and subsequent union of gametes (the collective term for the reproductive cells from either the male or female).
The DNA segment consists of two strands of the chain of bases. These two strands arte linked together at each of the base so that it forms a helical shape or a twisted ladder. The nature of the gene is such that each base in one strand can only pair with a specific base. Thus, adenine (A) could only pair with thymine (T) and guanine (G) could only pair with cytosine (C).
In spite of the consistency and the precision by which gene copies itself, mistakes, even if they are rare, occur. These mistakes are copied and become incorporated as part of the genetic information itself. Such mistakes are called mutations. If the mutation occurs in the somatic cell, then it is transmitted only from cell to cell in the same individual. But if it occurs in the germinal cell, then it may be transmitted to the next generation.
Genes provides the code for the synthesis of proteins through a process of transcription (process whereby the sequence of the bases in the DNA is transcribed by the mRNA in the nucleus for subsequent translation into the corresponding protein material) and translation (process of synthesis of the polypeptide chain based on the base sequence in the mRNA) involving the RNA and the ribosome in the cell.
The role of genotype and environment on the phenotypic
Genotype – the specific combination of genes in the diploid phase representing a phenotype. It is assemblage of gene in an individual.
- determined at the time of fertilization
- genetic make-up
- genetic constitution
Environment – the external factor, other than the genes that affects the character of an individual.
- non-genetic factor
- modifies phenotypic expression
- nutrition, climate, management, season, housing, etc.
Phenotype – the observable effect of a gene action. It is a function of gene and environment.
- outward manifestation of a genotype
- traits
- characteristics
- measurable
- expressed at different stages in life
- same as genotype if effect of environment is zero
- qualitative or quantitative
- production, reproduction and adaptation
- economically important or not
The G x E may be defined as the interaction between the genotype of the individual and the environment under which it is raised. The effect of Genotype x environment interaction when certain genotypes perform well under certain environments than other genotype, e.g. the Zebu (humped) cattle grow and reproduce better in arm tropical environment than the European (humpless) cattle.
Gene action
Genes may be active only when they occur in pairs of alleles during the diploid phase.
Allelic genes – genes that occupy the same locus (the specific location of a pair of genes in the chromosomes) in the chromosome (the colored bodies in the nucleus that contain the DNA).
Genes perform different roles. There are the structural genes which are directly responsible for the synthesis of certain biochemical products during cell metabolism and there are also the regulator genes which serve to control or regulate the function of other genes. Regulator genes may function in terms of quantity, quality or timing of the activity of certain structural genes.
Action of genes may be detected only from the phenotype. The action of genes as they influence genotypic values may be any or a combination of the following types:
a. Partial dominance or incomplete dominance – when a pair of allelic genes contribute independently to the genotypic value, the action of the gene is said to be additive. It is intra-allelic interactions.
- example:
when a red (NN) cattle is mated to a white (nn) one the progeny is roan (Nn)
b. Complete dominance – when a gene suppresses the expression of its allele, the former is called the dominant gene while the later is referred to as the recessive gene. It is intra-allelic interactions.
- example:
when homozygous pea comb (genotype PP) and a single comb (genotype pp) are crossed, the progeny will be heterozygous pea comb (genotype Pp)
c. Epistasis – from the Greek word which means “to stand upon”. It is a type of genetic interaction where a gene in one locus suppresses the action of a gene in another locus.
- example:
in chickens, the presence of a dominant gene C at the C-c locus and the dominant gene O at the O-o locus enables the individual to synthesize the color pigment for its feathers. But in the presence of a dominant I gene at the I-i locus, the action of C and O genes in inhibited.
The mechanics of inheritance
1. Gametogenesis and fertilization
- gametogenesis, the process of production of gametes
a. spermatogenesis – process of producing sperm cells
b. oogenesis - process of production of female gametes
- fertilization, the process of introduction of the sperm cell into the egg to form a zygote
2. The Mendelian inheritance
- laws of inheritance:
a. Laws of segregation – characters are determined by particulate factors (later given the term genes) and that these factors occur in pairs. In the formation of gametes, these factors are segregated so that only one of the pair is transmitted by a particular gamete.
b. Laws of independence – in the formation of gametes, members of one pair of genes segregate independently of other pairs.
3. Non-mendelian inheritance
- governed by many pairs of genes interacting with one another:
a. Sex-linkage – the state where a gene is located in the sex chromosomes
- mammals: XY-male; XX-female
- birds: ZZ-male; ZW-female
- homogametic, the sex that carries identical sex chromosomes, e.g. X and X in mammals
- heterogametic, the sex that carries the different sex chromosomes, e.g. X and Y in mammals
- there are known to be sex-linked, these include hemophilia and color blindness, barring plumage pattern and dwarfism
b. Autosomal linkage – state when the genes are located in the same autosome (the type of chromosome other than the sex chromosome)
- parental type of gametes, those that were similar to what the offspring received from the parents
- recombinant type of gametes, those that are different from what was received from either of the parents but were produced as a result of crossing over of chromosomes during meiosis
- test-crossing, crossing of an individual of unknown genotype
c. Non-nuclear inheritance – in this case, the females would play a larger role than the male in influencing the characteristics of the progeny since the sperm cells have very little, if any, cytoplasmic material
d. Quantitative traits
e. Continuous distribution
f. Sex-influenced
Maternal influence – the mother could further influence the characteristics of her offspring because of the maternal care she provides to her young.
Genes in Populations
- populations, a group of individual sharing a common gene pool
- gene pool, is the totality of the genes that could potentially be transmitted by individuals in a populations to the next generation
1. Genetic composition of animal population
-populations are characterized by the frequencies in which the genes and genotypes occur in them
2. Equilibrium population – a population in which the genes and genotypic frequencies do not change generation after generation
- Hardy-Weinberg Law, gene and genotypic frequency remain constant from generation to generation if population is large, there is random mating and there is absence or if there is balance of selection, migration and mutation. Hardy (British mathematician) and Weinberg (German physician) independently formulated the principle in 1908
- violation in Hardy-Weinberg equilibrium:
a. small population leads to genetic drift
b. assortative or dissortative mating
c. natural or artificial selection
d. movement of animals through importation of live animals, semen or embryo
e. change in biochemical structure of genes
3. Factors affecting change in the genetic composition of populations
a. Selection – process where certain individuals are able to contribute more progeny in the next generation than other individuals
- natural selection, natural forces
- artificial selection, intervention of man
b. Migration – process of movement of individuals from one population to another population
c. Mutation – spontaneous change in the biochemical or structural characteristics in the genetic material that results in a different biological action
d. Small population size
e. Non-random mating – occurs when some individuals do not have the same chances of mating with individuals of the opposite sex
- forms of non-random mating:
Assortative mating – individuals that are more phenotypically similar tend to mate more often
Disassortative mating – individuals which are less phenotypically similar tend to mate more often together than would be expected by chance
Inbreeding
Unit 7: Animal Breeding
- the art and science of genetic improvement of farm animals
1. Objectives of animal breeding
a. improve the quantity of production
b. improve the efficiency of production
c. improve the quality of farm animals
d. improve the aesthetic value of farm animals
2. Systems of animal breeding
a. Selection
b. Inbreeding – the process of mating animals that are closely related by descent
- increase genetic homozygosity
- inbreeding depression
- lowly heritable traits
- closest possible inbreeding animals is full-sib mating and parent-offspring mating
- inbreeding may be achieved by:
irregular systems, the relationship between mates in the pedigree is vary
regular systems, the relationship between mates is constant throughout the generations
c. Crossbreeding – the breeding of individuals from one population to individuals from another distinctly different population
- hybrid vigor or heterosis, a condition where the heterozygote is better than the average of the homozygote
F1 progeny is better than the average of the parents
Better than the average of the better parent
Occurring on lowly heritable traits
Caused by non-additive gene action (dominance, epistasis) higher than in the F1 than in the F2
Unit 8: Reproduction
- reproductive cycle and rate of genetic improvement
- frequency of ovulation and length of embryonic development:
Artificial insemination – techniques of introducing semen into the oviduct without the benefit of the male
- effective if the superior animal is the male
- benefit derived from artificial insemination:
a. the number of female that could be mated by a single male is increased dramatically
b. STD are minimized
c. male that are physically unable to mate naturally may still be used fro breeding
d. semen of bulls that have been long dead may still be used for inseminating cows
e. because the number of progeny that could be produced by a single male is increased the accuracy of evaluating the breeding value of a male is increased proportionately
Multiple ovulation and embryo transfer (MOET) – a process of hastening the reproductive rate of female animals
- effective if the superior animal is the female
- multiple ovulation, process by which the female animal is induced to simultaneously ovulate more eggs than what is normally shed
- embryo transfer, technique wherein a young embryo is collected from a donor female parent and then implanted into the uterus of a recipient female parent
Sexing semen – separating the fraction of the semen that would carry a much larger proportion of sperm cells carrying the Y-chromosomes than those that carry the X-chromosomes.
In vitro fertilization – experimentally induced biological processes outside the organisms.
Nuclear cloning – continued splitting of embryos that would lead to an indefinite duplication of an individual
Chapter 4: Slaughter, Processing and Marketing of Farm Animals
Unit 9: Slaughtering and fabrication
Unit 10: Composition of meat, milk and eggs
Unit 11: Basic principles of proper handling and processing of meat, milk and egg
Unit 12: Marketing of livestock and livestock products
Unit 9: Slaughtering and Fabrication
Definition of terms
Meat terms:
Meat – the carcass or carcass parts coming from animals sufficiently mature and healthy
Beef – meat from cattle more than one year old
Veal – meat from cattle less than one year old
Carabeef – meat from carabao more than one year old
Chevon – meat from goats
Pork – meat from swine
Mutton – meat from sheep
Lamb – meat from lambs
Venison – meat from deers
Hot meat – meat coming from an illegal source
Fresh meat – meat that has not undergone any substantial physical, chemical and microbiological changes from the time of slaughter
Meat by-products – the edible by-products from the slaughterhouse
Abattoir – the premises approved and registered as premises for slaughtering animals for human food
Cold slaughter – slaughtering an animal dead of some causes prior to slaughter
Fabrication – process of cutting carcasses into standard wholesale and retail cuts
Flaying – a ct of removing hide from animals
Corned meat – prepared meat cured by soaking with or without one or more of nitrate, nitrite, sugar dextrose, syrup, honey and with or without the use of spices
Curing – the addition of salt with or without nitrite, nitrate and sugar for the purpose of lengthening shelf life and/or enhancing the development of odor, color, and flavor
Quick freezing – freezing products at a temperature of -20 °F or lower
Green hams – unsmoked cured hams
Hot boned meat – meat deboned before the development of rigor mortis
Milk terms:
Pasteurization – it is a process of heating a foodstuff, usually liquid, for a definite time at a definite temperature and thereafter cooling it immediately. US public health service recommends heating milk to at least 145 °F for at least 15 seconds
Homogenization – fat globules are subjected to mechanical treatment, which breaks them down into smaller globules, uniformly dispersed in the milk
Certified milk – fresh milk of higher purity to be delivered to the customer within 36 hours. The number of bacteria is 10,000 or less per ml
Pasteurized milk – milk heated to a temperature of not lower than 145 °F for a period of not less than 30 minutes
Homogenized milk – milk than contains finer globules of butterfat than those present in fresh milk. It is prepared by passing fresh milk through small openings by pressure.
Evaporated milk – fresh milk which has been evaporated to a concentration of 73.7 % water. It contains 7 % protein, 7.9 % fat, 9.9 % lactose and 1 % minerals
Condensed milk – concentrated milk to which sugar has been added. It has 27 % water, 8.1 % protein, 54.8 % lactose and 1.7 % minerals
Filled milk – milk where the butterfat is replaced with vegetable fat such as coconut fat
Dried or powdered milk – dried milk obtained by evaporating the moisture from the milk solids
Recombined milk – dry skim milk, dry buttermilk plus butter oil
Reconstituted milk – milk powder plus water
Basic principles of selecting animals prior for slaughter
- the basic considerations in selecting animals are as follows:
a. sex consideration
b. age consideration
c. size consideration
d. class considerations
e. health consideration
f. finish considerations
Management of Animals Prior to Slaughter
There are four management practices given to animals prior to slaughter. These are fasting, allowing animals to relax, handling them gently and keeping them as clean as possible.
Fasting
Feed is not given to the animal, however, sufficient amount of water is provided. Simple stomach animals are fasted for 12 to 24 hours whereas the ruminants are fasted for 24 to 48 hours. Advantages of fasting include savings of feeds, ease of cleaning entrails and eviscerating carcasses, thoroughly bled and brightly colored carcass, long shelf life and low shrinkage of resulting meat.
Relaxed animal
No form of stress should be given to animal prior to slaughter. If stress cannot be avoided, animals must be given enough time to rest and gain their composure before they are slaughtered. One to three-day relaxation in the holding pen is enough to remove the effects of stress on the animal depending on the degree of stress.
The disadvantages of stress include loss of muscle glycogen, high temperature of carcass, low water holding/binding capacity of resulting meat, low aroma, flavor, texture and juiciness scores.
Handling animal gently
The part of an animal whipped, kicked or boxed prior to slaughter develops blood clots and red spots in the meat. Blood clots in meat are support for luxuriant growth of microorganisms and cause accelerated meat spoilage.
Clean animal
Good sanitation practice is best started by keeping the animal clean. One of the worst contaminants of meat is the micro flora abundant in feces.
Basic requirements in slaughtering animals
Basic factors to consider in slaughtering:
1. cleanliness of meat produced
2. hygiene or production
3. efficiency of meat inspection
4. adequacy of meat preservation
The slaughterhouse:
1. There must be complete facilities for the proper care of animals prior to slaughter.
2. The slaughterhouse should have separate rooms for the slaughter of swine and ruminants.
3. The slaughterhouse must have good drainage and ventilation, must be at least 100 meters away from residential houses and must have adequate pollution control device.
Classification of slaughterhouse in the Philippines:
1. AAA – those with facilities and operational procedures so adequate that the meat processed herein is eligible for sale in any market in and out of the country.
2. AA – those with facilities and operational procedures sufficiently adequate that the meat processed herein is eligible for sale in any market in the Philippines.
3. A – those with facilities and operational procedures of minimum adequacy as defined by the National Meat Inspection Commission (NMIC), the meat processes herein is eligible for sale only in the city or municipality in which the plant is located.
4. Non-accredited – those with facilities and operational procedures of less than minimum standards that must be closed until minimum standards are provided or achieved.
Slaughtering animals
1. Ante-mortem inspection – is determining whether an animal is fit for slaughter or not.
2. Stunning – is making animals unconscious but not killing them.
3. Sticking – animals must be stuck within 3 minutes after stunning.
4. Cleaning of the carcass – vary within species. There are three distinct methods of cleaning carcasses:
a. Flaying – is removing the hide. This is commonly done in carabaos, cattle, horses and goats.
b. Scalding – is submerging the carcass in hot water to loosen the hairs and scurf. Scalding is necessarily followed by scraping. The temperature of scalding water must be controlled at 130-180 °F.
c. Singering - is burning the hairs and scraping the hairs as soon as these are burned. This is commonly done in goats.
5. Evisceration – starts from the time cuts to open the carcasses are made and end when the slaughter by-products are removed from the body cavity.
6. Splitting/washing – splitting is cutting the carcass into two equal parts. The carcass must be splitted at the backbone, but the tail normally goes with the left side if it is not removed before cutting. Right after splitting the carcass is washed very thoroughly and the parts with blood clots are trimmed.
7. Post-mortem inspection – this is inspecting the carcass for final determination whether it is fit for human consumption or not.
8. Shrouding – is wrapping the carcass with cheesecloth.
9. Chilling – the chilling room where carcasses are laced after slaughter should have a temperature of 0-4 °C (32-40 °F).
10. Aging – is holding the meat for 7-14 days at 36 °F to improve tenderness and flavor of meat.
Meat fabrication
Fabrication is cutting carcasses into standard wholesale and retail cuts.
Four principles to follow in cutting carcasses:
1. thick portions must be separated from the thin ones
2. the tender parts must be separated from the less tender portions
3. the high priced cuts are separated from the less expensive parts
4. cuts must be made across the muscle fibers
Dressing yield of common livestock and poultry:
Dressing % = carcass weight / slaughter x 100
- obtained after 24-48 hours chilling without the head and internal organs
Lean-fat-bone yield = component / live weight x 100
Boneless recovery = boneless carcass / live weight x 100
Unit 10: Composition of Meat, Milk and Eggs
The meat
General characteristics
1. Meat is a high quality, concentrated and easily digested source of nutrients and is well balanced with regard to the relative amounts of specific nutrients which it contains. It is an excellent source of high quality protein, B-complex vitamins and of certain minerals.
2. Meat provides satiety unequaled by other food items, it can be prepared in several ways and it provides nutrients almost in the proportion and amount needed by the human body. Because of its high nutritive content, microorganisms also love to attack it, hence spoils fast at ordinary room temperature.
Physical component of meat
a. The basic structures that can be seen in meat are lean, fat, bone, skin, connective tissues, and blood vessels. Some meat cuts have also noticeable bone marrow inside the bones.
b. The lean or muscle is considered the most important among the components because of its palatability and nutritive value. Muscle also comprises the bulk of the carcass (about 50-65 %).
c. The fat tissues are the most variable constituents of meat. The amount of fat in the body is markedly influenced by the diet, age, exercise and other physiological factors.
d. The amount of connective tissues is also important in meat because it determines the tenderness or toughness of the meat. The higher the amount of connective tissues, the tougher the meat is.
Chemical composition of meat
- The chemical composition of meat is usually presented by its proximate composition. The proximate composition of meat varies depending on:
1. species from which the meat was obtained
2. degree of fatness to which the animal has been fed
3. specific cut used
4. extend of cutting and trimming
5. curing and processing treatment
Relationship of physical structure and chemical composition to the eating qualities of meat
1. kind of protein
2. amount of fat specifically marbling
3. carbohydrates
4. moisture content
5. nitrogenous extractives
6. connective tissues
7. muscle fibers bundle
Nutritional value of meat
1. connective tissues proteins have high amount of proline, hydroxyproline, and glycine and has low tryptophan and tyrosine
2. meat is an excellent source of the B vitamins, phosphorus and iron but relatively low in calcium. The cooking and processing of meats do not appreciably affect the quantity or availability of the mineral elements present as long when mineral salts are added.
The milk
General characteristics of milk
1. Milk ranges from a bluish white to almost golden yellow color. In large quantities, milk appears entirely opaque.
2. Milk has no pronounced taste but slightly sweet to most persons. Freshly drawn milk has low characteristics odor but gets lost upon exposure to air.
3. The pH of fresh milk is about 6.5. When milk is allowed to stand undisturbed for a few hours, a layer forms on the surface. This layer is the cream which is composed of fat globules.
4. Since milk is very nutritious, microorganisms grow in it very fast and spoil it. The normal freezing point is -0.545 °C.
Chemical composition of milk
1. Water is the principal constituents of milk. It is about 78-88 % (average of 87 %) of the fresh whole milk.
2. Fats are also present in the form of fat globules which amount to 3-10 % of milk. Fats are very good absorber of flavor and odor and usually come into two forms:
a. true fat (glycerides)
b. associated substances (lecithin, cholesterol, carotene, vit. A, D and E)
3. Carbohydrates in milk are in the form of lactose, which is about 4-5 % (average of 4.9 %) of the milk. Lactose is complex disaccharide made up of glucose and galactose. This is easily fermented by microorganisms to lactic acid.
4. Nitrogenous component of milk is made up of 95 % protein and 5 % non-protein. The milk has around 3-6 % protein. The 78.5 % of protein in milk is casein while 16.5 % rest is milk serum protein. The protein milk is considered as of high quality; almost the same as in meat, but a little bit lower than that of egg. Milk protein is slightly deficient is sulfur containing amino acid.
5. Milk has 0.7-1.0 % ash or inorganic minerals. Milk is a rich source of calcium, magnesium, phosphate and citrate.
The colostrums has 73.79 % water, 1.17 % protein, 6.74 % fat, 2.30 % lactose and 1.0 % ash while human has 87.6 % water, 1.2 % protein, 3.8 % fat, 7.0 % lactose and 0.4 % ash.
Nutritional value of milk
1. Milk contains broad distribution of nutrients. Milk is especially rich in high-quality protein, calcium, phosphorus, riboflavin, ands other B vitamins. It is poorer source of vitamin D, C, and iron.
2. Milk protein is one of the highest quality proteins. The only principal deficiency of milk protein is the sulfur containing amino acids: cystine and methionine. It is very rich in lysine. Milk lipids, however, contain high saturated fatty acids and low linoleic acid and linolenic fatty acid.
3. The fat-soluble vitamins of milk exist partially in a free state and partially bound to proteins. There, the biological activity of the bound forms may-depend on their release upon ingestion.
The egg
General characteristics
The egg is compact package of well-balanced food nutrients. Eggs have high protein, very low in carbohydrate, have high vitamin A, riboflavin and vitamin D. it is richest source of iron in animal foods. One chicken egg weighs on the average about 50-60 grams. Calcium is in the form of CaCO3.
Constituent of egg
The egg is basically composed of around 31 % yolk, 59 % albumen or white and 10 % shell. The yolk is made up of 47-48 % moisture, 16 % protein, 32-35 % ether extract or fat and around 1 % carbohydrate. The ether extract component of yolk contains phospholipids, triglycerides and cholesterol. On the other hand, the albumen is made up of 87-89 % moisture, 9.7-10.6 % protein, 0.5-0.6 % ash, 0.03 % fat and 0.5-0.9 % carbohydrates.
Common tests to determine composition of meat, milk and egg:
Composition Laboratory Analyses
Meat Milk Egg
Moisture Oven drying Oven drying /use of lactometer Oven drying
Total solids Oven drying Use of lactometer Oven drying
Ash Ignition Ignition Ignition
Crude fat Ether extraction /Babcock test Ether extraction Babcock test
CP Kjeldahl analysis Kjeldahl analysis Kjeldahl analysis
Casein N/A Walker method N/A
Measures of egg quality:
1. Whole egg characteristics
• Size, shape, color, texture, cleanliness, uniformity of eggs
• Floatation test
2. Candling characteristics
• shell, air cell, yolk, white and germ
• bubbly air cell – state, weak shell membrane, rough handling
• air cell moves – broken inner membrane
• normal yolk – faint shadow at the center of egg
• abnormal yolk – moves freely and casts darker shadow
• old egg – floats
• high quality egg has no germ development (blood begins to show after 48 hours at 100-103 °F)
3. Broken out odor, flavor, physical characteristics
• normal – yolk is well rounded
• old – flattered and spread out
• haugh unit – height of yolk – log of albumen
- height corrected to standard egg weight of 2.03
HU = 100 log {H – [G (30 W – 37 – 100) + /g] / 100}
HU – Haugh units
H – Albumen height
G – Gravitational constant
W – Weight of eggs
- simplified formula:
HU = 100 log (H + 7.57 – 1.7 W – 37)
4. Other measures of quality
• yolk index = measures of the standing up quality of yolk
= height of yolk / diameter
0.42 – 0.4 = normal
0.25 = low
Unit 11: Basic Principles of Proper Handling and Processing of Meat, Milk and Egg
Causes of deterioration
Categories:
1. Biological forces. Biological spoilages may also be brought about by flies, rodents and cockroaches. Spoilages of these kinds are however easy to control. Working in ideal rooms may entirely eliminate insect spoilage problems.
2. Chemical forces. Oxidation is a common chemical cause of meat, milk and egg deterioration. Oxidation of the fats causes rancidity while oxidation of the color pigment in meat causes darkening.
3. Physical forces. Dehydration and enzymatic action are two of the physical processes causing food deterioration. These two are expensive to minimize and very impractical to completely stop or control.
Processing of meat
Meat processing refers to any or combination of process utilized in altering fresh meat.
1. Cold storage may be divided into chilling and freezing.
a. Chilling is subjecting meat to a temperature of 32-40 0F (0-4 0C). There is rapid cooling but there is no hardening and freezing of meat juices.
b. Freezing of meat is either slow or quick freezing. The meat hardens in 30 minutes in quick freezing. Longer time is required in slow freezing. Quick freezing on the other hand can be accomplished by blast, deep, cryogenic, direct immersion, indirect immersion, indirect contact and spray freezing. Quick freezing is more advantageous than slow freezing because there is less destruction of the muscle fibers, less drip, minimal loss of water holding capacity and flavor of product.
2. Drying meat is lowering the available water in meat. This can be done by withdrawing the water by binding the water and renders it unavailable for microbial growth.
3. Salting is accomplished by the addition of salt, hypochlorite of calcium and/or other salts. Through osmosis, salts withdraw water from meat and causes plasmolysis of bacterial cells. Salts also ionize to yield chlorine ion, which is harmful to organisms. Other action of salts include reducing the availability of oxygen in the moisture, sensitizing bacterial cells to carbon dioxide, reducing the action of proteolytic enzymes and accelerating development of rancidity.
4. Canning is hermetically sealing of meat in a container and then subjecting it to thermal process. All the organisms present are killed in this process and the product is considered commercially sterile.
5. Curing started as a method of meat preservation; however, as time went by, people developed the liking for cured flavor. There are basic ingredients required in meat curing. These are salt, sugar, and nitrate/nitrite.
Ordinary table salt is the major portion of the curing ingredients. It inhibits the growth of putrefying bacteria, hardens muscle fibers and draws out moisture from the meat. Together with other ingredients, it adds desirable flavor and texture to the meat.
Sugar adds flavor, helps overcome saltiness and counteracts the toughening effect of salt. It is also utilized as media by some beneficial organisms.
Nitrate/nitrite helps develop cured color and flavor and inhibit microbial growth.
Quality in meat
The word quality infers superiority and degree of excellence
Measures used to evaluate quality in meat:
1. Lean color
- Bright colored meat gives so much appeal to the consumer
- Indicates how long a cut of meat has been held on meat stall
- Improves selling or marketability of meat
- Helps identify species of animals from which the meat is taken
2. Lean firmness
3. Lean texture
4. Marbling
5. Age or maturity of the carcasses
Milk processing
1. Straining – right after milking, the milk is strained using sterilized cheesecloth.
2. Cooling milk – the milk should be cooled to 50 0F of lower as soon as it is milked out to minimize microbial growth.
3. Clarification and filtration – this process is done to further remove dirt, which were not removed during straining. Clarification is the by the use of the principle of centrifugation, while filtration is using the principle of filter paper.
4. Separation – this is separating the cream and the skim milk. This can be accomplished by either gravity method or using a mechanical cream separator.
5. Pasteurization – treating milk with heat thereafter followed by rapid cooling to destroy bacteria. About 98.99 % of bacterial cells die. Pasteurization can be done by either:
a. Holding process – milk is heated to 145 0F (62. 8 0C) for 30 minutes, then cooled rapidly/.
b. Flash process:
- HTST (High temperature short time) – milk is heated at 165-185 0F (73.9-82.2 0C) for 15 seconds.
- UHT (Ultra high temperature) – milk is heated at 192-194 0F (80-90 0C) for 1 to 4 seconds.
6. Homogenization – forcing milk through small opening under high pressure. Normal pressure is from 2,500 – 5,000 psi. Fat particles are reduced to less than 2 microns in diameter.
Forms of milk in the market
1. Fresh whole milk
2. Whole milk powder – water is removed
3. Skim milk – fat or cream is removed
4. Skim milk powder (SKMP) – water is removed from the skim milk, also known as non-fat dry milk
5. Evaporated milk – some water removed
6. Condensed milk – more water removed plus water
7. Filled milk – SKMP = vegetable oil + Vitamin A and D
8. Homogenized – small fat globules (2,500-5,000 psi)
9. Flavored milk – SKMP + water + flavor
10. Whey powder
Unit 12: Marketing of Livestock and Livestock Products
Methods of marketing livestock in the Philippines
1. Livestock market/concentration yards - farmers or traders bring their animals to the concentration yards to sale. Markets usually have facilities for the care of animals. The transactions could be:
trader to trader;
farmer to trader; and
trader to farmer.
2. Barrio agents – perform one or both of the following:
buy livestock from scattered backyard farms and sell these to viajeros; and
act as a viajero or wholesaler and sell livestock, directly to retailers. These agents are highly skilled especially in live weight estimation.
3. Wholesalers or viajeros – buys livestock in wholesale quantity, transport the livestock and resell them to wholesalers, retailers and/or processors.
4. City dealers – are the intermediaries between the provincial viajeros and the wholesalers in the cities.
5. Retailers – are those who buy animals and sell them to consumers. These are very common in goat marketing.
6. Contract growing schemes – there are several approaches used in contact scheme. In all of the schemes, a mother company takes the animals produced and takes care of the processing before final sale to consumers.
Problems commonly encountered in the marketing of livestock
1. No grade standards
2. Lack of integrated information
3. Difficulty of transporting animals
4. Cost of transportation is very high
5. Lack of suitable public transport system
Meat and Meat Products Marketing
Traditionally, the meat distribution system is multi-layered with many middlemen involved in the whole process. The most common is the five (5) level distribution system.
Producer ------- Barrio agent ------- Wholesaler ------- Retailer -------- End consumer
However, recent trends indicate that more producers have resorted to direct marketing system in an effort to reduce or totally eliminate the middlemen involved and maximize profits.
Producers ----- retailers
• wet market
• institutional markets
- supermarkets
- groceries
- hotels
- restaurants
Types of meat markets
1. Retailers
a. Wet markets – are those meat stalls in public markets where meat are usually hung in bulk and sliced only when a customer comes. Wholesalers usually supply meats for these markets.
b. Supermarket style/meat shops – are components or grocery stores, supermarket or individual meat shops. Meats are properly fabricated and handled.
2. Wholesalers
a. pack trading
b. packers to retailers
c. retail outlets
d. institutional outlets
Chapter 2: Animal Nutrition
Feed Nutrients
Nutrition is the series of process by which an organism takes in and assimilates food for promoting growth and replacing worn-out or injured tissues.
A nutrient is any feed constituent or group of feed constituent of the same general chemical composition that aids in the support of life.
Digestion is the breakdown of feed particles into suitable products for absorption.
Absorption is the transfer of substances from GIT to the circulatory (blood or lymph) system.
A metabolism is the combination of anabolic and catabolic reactions occurring in the body with the liberation of energy.
Enzymes is a complex protein produced in living cells that causes changes in other substances within the body without being changed itself (organic catalysts).
Classes of nutrients
Water – the cheapest and most abundant nutrient. It makes up to 65-68 % of animal BW at birth and 45-60 % of BW at maturity.
- accounts 90-95 % of blood and many tissues contain 70-90 % water
- found in:
1. Intracellular water – mainly muscles and skin
2. Extracellular water – mainly interstitial fluids, blood plasma, lymph, synovial and cerebrospinal fluids.
- functions:
1. transport of nutrients and excretions
2. chemical reactions and solvent properties
3. body temperature regulation
4. maintain body cells
5. lubricates and cushion joints and organs in the body cavity
- deficiencies:
1. reduced feed intake and palatability
2. weight loss due to dehydration
3. increased secretions of N and electrolytes such as Na and K
Carbohydrates – made up of C (40 %), H (7 %) and O (53 %). It makes up approximately ¾ of plant dry weight and thus the largest part of animals food supply.
- formed by photosynthesis
- classification:
1. Monosaccharide – includes hexose (glucose, fructose, galactose) and pentose (arabinose, xylose, ribose)
2. Disaccharide – includes sucrose, maltose, lactose, cellobiose
3. Polysaccharide – includes starch (amylase, amylopectins, glycogen), cellulose, mixed polysaccharide (hemicellulose, pectin), and lignin
- functions:
1. source of energy
2. source of heat
3. building stores for other nutrients
4. stores in animal body by converting to fats
- deficiencies:
1. ketosis
2. diabetes mellitus
Fats (lipids or ether extract) – made up of C (77 %), H (12 %), and O (11 %). It is insoluble in water but soluble in organic solvents.
- fat will yield 2.25 times more energy than CHO or proteins
- classifications:
1. Simple lipids
2. Compound lipids – includes phospholipids (phosphoric acid and nitrogen), glycolipids, and lipoproteins
3. Derived lipids – includes fatty acids and sterols
- functions:
1. dietary supply
2. source of heat, insulation and protection for animal body
3. source of essential fatty acids (linoleic, linolenic and arachidonic acid)
4. serve as carrier for absorption of fat soluble vitamins
- deficiencies:
1. skin lesions, hair loss and reduced feed growth rate
2. ketosis (catabolism of body fat)
3. fatty liver (abnormal metabolism of liver)
Proteins – made up of C (53 %), H (7 %), O (23 %), N (16 %) and P (1 %). It is the principal constituents of the organ and sifts structures of the animal body.
- true proteins, composed of amino acids
- non-protein nitrogen (NPN), not true protein in nature but contain N and can be converted to protein by bacterial action, e.g. urea
- crude proteins (CP), composed of true proteins and any nitrogenous products (CP = % N x 6.25)
- protein quality refers to the amount and ratio of essential amino acids present in protein.
- classifications of proteins:
1. Simple (globular) proteins – yielding only amino acids or their derivatives upon hydrolysis, e.g. albumins, histones, protamines, globulins, glutelins, and prolamins
2. Fibrous proteins – constitute about 30 % of total protein in animal body, connective tissue, e.g. collagens, elastin, keratins
3. Conjugated proteins – a simple proteins are combined with non-proteins radical, e.g. nucleoprotein, glycoprotein, phosphoproteins, hemoproteins, lecithoproteins, lipoproteins, metalloproteins.
- functions of proteins:
1. basic structural unit of the animal body
2. body metabolisms
- classifications of amino acids:
1. Essential amino acids – those amino acids which are essential to the animal and must be supplied in the diet because the animal cannot synthesize them fast enough to meet its requirements. Examples: phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, histidine, arginine, leucine, lysine
2. Non-essential amino acids – those amino acids which are essential to the animal but are normally synthesized or sufficient in the diet and need not be supplement. Examples: alanine, asparagines, aspartic acid, cysteine, cystine, glutamic acid, glutamine, glycine, hydroxyproline, praline, serine, tyrosine
- deficiencies:
1. reduced growth rate and feed efficiency
2. anorexia
3. infertility
Minerals – are inorganic solids, crystalline chemical elements. It makes up 5 % of an animal body on dry weight basis.
- ash, total mineral content of plants or animals
- functions:
1. skeletal formation and maintenance
2. protein synthesis
3. oxygen transport
4. fluid balance (osmotic pressure)
5. regulating acid-base balance of enzyme systems
6. activators and/or component of enzyme system
7. mineral-vitamin relationship
- classifications:
1. Major mineral or macro minerals – normally present at greater level in animal body or needed in large amounts in the diet.
- examples:
a. Sodium and chlorine – for formation of digestive juices, control of body fluid concentration, control of body fluid pH, and nerve muscle activity.
deficiency:
• unthrifty appearance and impaired performance
• disrupted nerve and muscle function
• nervous prostrations
b. Calcium – for bone and teeth formation, nerve and muscle function, acid-base balance, and milk production and egg production
deficiency:
• rickets
• osteomalacia or osteoporosis
c. Phosphorus – for bone and teeth formation, component of protein in the soft tissues, milk production and egg production, and metabolic processes.
deficiency:
• rickets
• osteomalacia or osteoporosis
• poor appetite, slow gain, lowered milk production, low blood phosphorus and unthriftiness
• animal may eat soil and chew on nonfeed objects
d. Magnesium – necessary for many enzyme systems, play as a role in CHO metabolisms, and necessary for the proper functioning of the nervous system.
deficiency:
• hypermagnesemic tetany – hyper-irritability of neuromuscular system producing hyperexcitability, incoordination and frequently death
e. Potassium – for osmotic pressure, acid-base balance, rumen digestion, and intracellular cation in neuromuscular activity
deficiency:
• decreased feed consumption
• lowered feed efficiency
• slow growth
• stiffness
• emaciation
f. Sulfur – for component of the amino acid (cystine and methionine) and vitamins (biotin and thiamine), synthesis of sulfur containing amino acids in the rumen, and the formation of various body compounds
deficiency:
• protein deficiency – general unthrifty conditions and poor appearance
2. Minor/trace or micro minerals – normally present at low levels in animal body or small amount in the diet.
- examples:
a. Iron – necessary for hemoglobin formation, essential for the formation of certain enzymes related to oxygen transport and utilization, and formation of certain compounds which serve iron stores in the body, e.g. ferritin (found primarily in the liver and spleen) and hemosiderin (found mainly in the blood)
deficiency:
• low blood hemoglobin
• labored breathing
• listlessness
• pale eyelids, ears and nose
• flabby, wrinkled skin
• edema of head and shoulder
b. Iodine – for production of thyroxine by the thyroid glands.
deficiency:
• goiter at birth or soon thereafter
• dead or weak at birth
• hairlessness at birth
• infected navels esp. foals
c. Cobalt – for component of Vit. B12 molecule and rumen synthesis of Vit. B12.
deficiency:
• poor appetite
• unthriftiness
• weakness
• anemia
• decreased fertility
• slow growth
• decreased milk and wool production
d. Copper – for iron absorption, hemoglobin formation, synthesis of keratin for hair and wool growth, and various enzyme systems.
deficiency:
• low blood and liver copper
• bleaching of hair in cattle
• abnormal wool growth in sheep
• abnormal bone metabolism
• muscular incoordination
• weakness at birth
• anemia
e. Fluorine – for reduces incidence of dental caries, and retards osteoporosis in mature animals.
deficiency:
• excessive dental caries esp. children
f. Manganese – for influencing estrus, ovulation, fetal development, udder development, milk production, and growth and skeletal development.
deficiency:
• delayed estrus
• reduced ovulation
• abortions
• resorptions
• deformed young
• poor growth
• lowered serum alkaline phosphates
• lowered tissue manganese
• knuckling over in calves
g. Selenium – for Vit. E absorption and utilization, component of enzyme (glutathione peroxidase – destroy toxic peroxide in the tissues thereby having a sparing effect in the Vit. E requirement), and maintenance of normal cell functions and membrane health.
deficiency:
• muscular dystrophy (white muscle disease)
• retained placenta in cows
• heart failure
• paralysis
• poor growth
• low fertility
• liver necrosis
• pancreatic fibrosis in chicks
h. Zinc – prevents parakeratosis, promotes general thriftiness and growth, promotes wound healing, related to hair and wool growth and health, and deficiency impairs testicular growth function.
deficiency:
• parakeratosis
• general thriftiness
• poor growth
• unhealthy looking hair or wool
• slow wound healing
Vitamins – is organic components of natural food. It is present in foods in minute amounts and effective in small amounts. It is also essential for development of normal tissue necessary for metabolic activity but do not enter into structural portion of the body. Other function is necessary for growth and maintenance.
- cannot be synthesized by the animal
- related substances:
1. Provitamins or precursors (carotene)
2. Antivitamins, vitamin antagonists or pseudovitamins
- 2 forms of vitamins:
1. Fat-soluble vitamins – can be dissolved in fats
a. Vitamin A – is also known as retinol. It promotes the development of visual pigments. It is indispensable for the formation of epithelial tissues and improves the resistance to infection.
b. Vitamin D – also known as calciferol. It regulates the incorporation of Ca and P into the bone matrix and the Ca absorption from the intestinal lumen.
c. Vitamin E – also known as tocopherol. It works as a biological antioxidant (detoxifying agents). It participates as a component of the respiratory chain and function in nucleic acids metabolisms and in endocrine glands.
d. Vitamin K – also known as menadione. It functions in the blood coagulation system. It acts in the maturation of the bone structure.
2. Water-soluble vitamins – can be dissolved in water
a. Vitamin B1 – also known as thiamin. It participates in the process of carbohydrate metabolisms.
b. Vitamin B2 – also known as riboflavin. It acts in the respiratory chain as a constituent of the flavin enzymes concerned with H transfer.
c. Vitamin B6 – also known as pyridoxine. It is active in amino acids metabolisms as a coenzyme of several enzyme systems.
d. Vitamin B12 – also known as cyanocobalamin. It is essential in the reduction of one carbon compounds in the fat and protein metabolisms.
e. Biotin – also known as Vit. H. It is necessary for gluconeogenesis and fatty acid synthesis where it acts in carboxylation reactions.
f. Folic acid – it acts in the one carbon metabolisms where it is indispensable in the formation of amino acids and nucleic acids.
g. Nicotinic acid – also known as niacin or nicotinamide. It acts as an active group of different coenzyme which is related to the citric acid cycle.
h. Pantothenic acid – part of coenzyme A which occupies a central position in the intermediary metabolisms by activating weakly active acids.
i. Vitamin C – also known as ascorbic acid. It is essential in the formation and maintenance of skeletal tissues. It participates as an oxidation-reduction system in cellular oxidation processes and also involved in defensive mechanisms.
- vitamin deficiency in poultry:
1. nervous disorders such as convulsions
2. skin or mouth lesions
3. discharge from eyes or swollen, pasted eyelids
4. reduced resistance to infectious diseases
5. poor feathering
6. bone abnormalities
7. leg weakness or paralysis
8. egg production reduced or below full potential
9. retarded growth
10. hatchability reduced or below full potential
- vitamin deficiency in pigs:
1. muscular incoordination of other nervous signs
2. reduced feed intake
3. impaired vision or blindness
4. scours and/or vomiting
5. hair, skin and claw problems
6. anemia
7. impaired feed conversion
8. lameness or unsteady gait
9. poor reproduction
10. retarded growth
11. weakness or increased mortality of newborn pigs
- vitamin deficiency in ruminants:
1. muscular incoordination or other nervous signs
2. reduced feed intake
3. impaired vision or blindness
4. digestive disturbances
5. rough hair coat
6. degeneration of heart and skeletal muscle
7. poor reproduction
8. retarded growth
9. bone deformities or swollen joints
Unit 4: Digestive Systems and Absorption of Food Nutrients
The digestive system consists of the teeth, mouth, gullet (esophagus), stomach, liver, intestine, pancreas, and rectum.
Digestion begins in the mouth where feed is broken down into small pieces by the teeth and mixed with saliva before being swallowed.
In the stomach feed is mixed with the juices to form a soft paste. This then passes into the intestine where bile from the liver and juices from the pancreas are added. The action of these juices is to break down the feed and allow the nourishment it contains to be absorbed by the blood in the walls of the intestine. Waste matter collects in the rectum and passes out of the body through the anus (or cloaca in birds).
Splanchnology is the name of the study of digestive system.
Animal’s carnivore, omnivore and herbivores
Animals are divided into three groups:
Carnivores which eat meat, e.g. dog, lion
Omnivores which eat meat and plants e.g. pig
Herbivores which eat plants e.g. cow, horse
The digestive system of omnivores and carnivores is as described above. In herbivores the digestive system is very large because they eat large amounts of grass.
- The horse, donkey and mule are herbivores but do not chew the cud. They are non-ruminants.
- Cattle, goats, sheep and buffalo chew the cud. They are ruminants.
Digestion – includes 2 processes the mechanical process and chemical process. The mechanical process includes chewing (mastication) and muscular contractions of the GIT. The chemical process involves the action of acids in the GIT or enzymes produced by the microorganisms located in various parts of the GIT.
- types of GIT:
1. Non-ruminant or simple stomach
2. Ruminant or compound stomach
3. Avian type or modified-simple stomach
Non-ruminant
- includes the pigs, horse, rabbit, dog and cat and humans
- major parts includes the mouth, esophagus, stomach, small intestine, large intestine
Mouth – consists of tongue (grasping food), teeth (mastication of food), and salivary gland (produce saliva which contains water to moisten food, mucin to lubricates food for easy swallowing, bicarbonates salts to buffer or regulate pH and salivary amylase to start CHO digestion).
Esophagus – a muscular tube. It allows passage of food from mouth to stomach.
Stomach – a muscular digestive organ. It is for storage of ingested feed, mechanical breakdown, and production of HCl, enzymes and mucus.
- 3 regions:
1. Cardiac – cells produce mucus that protects the stomach lining.
2. Peptic – cells produce HCl, pepsin (proteolytic enzyme) and mucus.
3. Pyloric – mucus producing cells.
Small intestine – has 3 divisions, namely:
1. Duodenum – first section that is very active site of digestion that receives secretions from pancreas, liver, and intestinal walls.
2. Jejunum – middle sections that involved in nutrient absorption.
3. Ileum – last section that also involved in nutrient absorption.
Large intestine – has 3 sections, namely:
1. Cecum – first section that is large in horse and rabbit and well developed as in the horse that contains many bacteria which produced enzymes that digest fiber.
2. Colon – middle section that involved in reabsorption of water.
3. Rectum – last section
Ruminants
- includes the cattle, sheep, goat and carabao
- 4 compartment stomachs:
1. Rumen – large muscular compartment which fills the left side of the body cavity. It is also called paunch.
- has papillae that covered by projections for absorptions of nutrients
- provide favorable environment for protozoa and bacteria
- pregastric fermentation produces enzymes that breakdown fiber as well as starch and protein, and volatile fatty acids (VFA) such as propionic acid, butyric acid and acetic acid.
- water soluble vitamins and vitamin K
- bacterial synthesis of amino acids and protein
- favorable conditions:
a. anaerobic environment
b. constant warm temperature
c. moisture
d. constant food supply
e. mixing
f. removal of toxic end-products
- additional functions:
a. storage
b. soaking
c. physical mixing and breakdown
2. Reticulum – also called honeycomb. The main function is to move food into the rumen or omasum and collect of dense particles of food and in regurgitation of ingesta during rumination.
- rumination, movement of ingesta back up the esophagus to the mouth for additional mechanical breakdown (chewing the cud)
3. Omasum – is a round muscular organ which contains many muscular laminae. It is also called many fold or many plies.
- functions:
a. controlling passage of ingesta to lower tract (act as pump)
b. reduce particles size of ingesta
c. absorption
4. Abomasums – also called as true gastric stomach. It is identical to the gastric stomach of non-ruminants.
- small intestine and large intestine is similar in form and functions as in the non-ruminants
- additional features in ruminants:
1. Esophageal groove – found at the base of the esophagus and when stimulated by sucking forms a tube which empties into the abomasums. The main function is to direct milk obtained from sucking to escape microbial digestion in the rumen.
2. Rumination – described as controlled vomiting. It is control set of contractions of esophagus, reticulum, and rumen that allows ingesta to be swallowed regurgitated back up to the esophagus where fluids swallowed again. It has additional remastication and reswallowing of solids.
3. Eructation – belching of gas. It is removal of large volumes of gas produced in the rumen. It is contractions of the upper part of the rumen force the gas up the esophagus and from there the gas penetrates into the trachea and lungs.
When the ruminant has finished eating, the food is brought back up and rechewed. This is called chewing the cud or rumination. If the animal stops ruminating this is a sign of ill health.
Ruminants make a lot of gas in their stomachs and belch once every minute, (unlike people they belch silently). If the belching stops the stomach swells with gas. We call this bloat or tympany.
The rumen moves regularly and contracts about once every minute. By putting your fist on the left flank (in the hollow behind the ribs) you will be able to detect the contractions. Regular contractions are a sign of good health.
Avian type
– consists of beak, crop, proventriculus, ventriculus, small intestine and large intestine, e.g. all birds.
Beak – collects particles of feed and breaks some large particles into smaller pieces. The tongue and salivary glands are present and saliva does not contain salivary amylase.
Crop – enlarged area that connected to the esophagus. The functions are for temporary storage and moistening of food, place for salivary amylase to work, and microbial fermentation in some species.
Proventriculus – true stomach of birds. It is the site of HCl and pepsin production. The ingesta pass through the proventriculus very rapidly (14 seconds).
Ventriculus – commonly called gizzard. It is muscular area that contains grit. The muscular contractions which are involuntary aid in the mechanical breakdown of food and it is similar to the mastication by the teeth in the non-ruminant and ruminant.
Small intestine – it is similar to the small intestine of the non-ruminant and ruminant.
Large intestine – has 2 areas (called ceca) which are very similar in form and function to the cecum of non-ruminant and ruminants.
The bird has no teeth, food is swallowed whole and goes into the crop where it is stored and mixed with saliva. If you feel the crop you can tell if a bird has been feeding or not.
The feed passes from the crop into the stomach where it mixes with the juices before passing into the roundish, thick walled, muscular organ called the gizzard. The gizzard contains small stones which the bird has eaten to help the gizzard to grind up the food for digestion. Nutrients are absorbed as ground up feed passes along the intestine.
Birds do not produce liquid urine. Waste from the kidneys forms a thick white material which is mixed with the feces (droppings). Both are then passed out through the cloaca. The duck produces wetter droppings than the chicken.
Nutrient Basic unit
Protein ---------------------------------------------------------- amino acids
Starch -------------------------------------------- glucose (non-ruminant), VFA and lactic acid (ruminant)
Cellulose ------------------------------------------------------- VFA
Sucrose -------------------------------------------------------- glucose and fatty acids
Lactose ------------------------------------------------------- glucose and galactose
Lipids ---------------------------------------------------------- fatty acids and glycerol
Minerals ------------------------------------------------------- any soluble form
Vitamins ------------------------------------------------------- any soluble form
End products of enzymes
1. Saliva
- salivary amylase, starch to maltose
2. Rumen
- microbial cellulose, cellulose to VFA
- microbial amylase, starch to VFA and lactic acid
- microbial proteases, protein to amino acids and NH3
- microbial urease, urea to CO2 and NH3
3. Stomach, abomasums, proventriculus
- pepsin, protein to polypeptides
4. Pancreas
- trypsin, protein to peptides and amino acids
- chymotrypsin, protein to peptides and amino acids
- carboxypeptidase, protein to peptides and amino acids
- amylase, starch to maltose
- lipase, lipids to fatty acids and glycerol
5. Small intestine
- aminopeptidase, protein to peptides and amino acids
- dipeptidase, peptides to amino acids
- maltase, maltose and glucose
- lactase, lactose to glucose and galactose
- sucrase, sucrose to glucose and fructose
Absorption – occurs primarily in small intestine.
- villi, small projections which line the small intestine
- papillae, projections which line the rumen (VFA)
- occurs as the result of diffusion or active transport
- diffusion, movement of the basic units from areas of high concentration (GIT) to area of lower concentration (blood)
Metabolisms – occurs only after basic units of nutrients have been absorbed into the blood. The chemical reactions performed by the cells to use the basic units of the nutrients for their specific functions (glucose – for energy and amino acids – for protein synthesis).
- reactions functions in series and are described as pathways or cycles:
1. Embden myerhof pathway of glucose metabolisms
2. Krebs cycle
- has two forms:
1. Anabolisms – building up of tissues
2. Catabolism – breaking down of tissues
Unit 5: Ration Formulation
Feeds – naturally occurring ingredients in the rations of animals that are used to sustain life.
Classification of feeds
1. Roughage – livestock feeds that contain more than 18 % crude fiber when dry.
- examples:
a. hay
b. silage
c. pasture
d. fodder
2. Concentrates – livestock feeds that contain less than 18 % crude fiber when dry.
- examples:
a. meat scraps
b. meat and bone meal
c. fish meal
d. blood meal
A ration is the amount of feed given to an animal to meet its needs during a twenty-four hour period.
A balanced ration is one that has all the nutrients the animal needs in the right proportions and amounts.
Ration formulation is a process of combining different feed ingredients to a proportion that will give the animals the proper amount of nutrients needed at their particular stage of production.
Important consideration in feed formulation
1. acceptability
2. digestibility
3. cost
4. presence of anti-nutritional factors and toxins
Methods of ration formulation
1. Pearson square method
2. Simultaneous equation method
3. Two-by-two matrix method
4. Trial-and-run method
5. Linear programming
Pointers in ration formulation
1. listing of nutrients requirements of animals
2. nutrient analyses of feed ingredients and cost to be used
3. usage and limitation of feed ingredients
4. check ration for each nutrient content cost/kg of mixed feed
Ration functions
1. Maintenance
- feed/ration or nutrients for the following purposes:
a. maintain BW or size
b. support essential life processes
c. maintain body temperature
d. maintain the different body secretions
- basal metabolisms or fasting catabolism, minimum energy expenditure to maintain essential life processes.
- energy requirement for maintenance is related to the body surface are or metabolic body size.
- activity increment, energy expenditure due to normal body movements and associated activities.
- protein requirement for maintenance is made up of two portions:
a. Endogenous urinary nitrogen (EUN) – normal wear and tear of the body organs and tissues
b. Adult growth functions – feathers, hairs, hoofs, nails
2. Growth
- correlated increase in the mass of the body to reach the size at maturity fixed by heredity.
- reflected in increased weight and size
- characterized by:
a. increase in the number of cells
b. increase in size of the cells
- optimum growth is in high protein level and good protein quality (essential amino acids)
- energy (CHO, fats, CHON) is the driving force for tissue synthesis or anabolisms
- high energy ration will make it faster and shorten the feeding or growth period
- low energy ration will slow down the growth rate and thus lengthen the growth rate
- ways of energy restrictions:
a. limit the total feed intake
b. lower the energy content or density of the ration
- energy to protein ratio is an important factor in the efficiency and economy of growth
- measures by the average daily (ADG) and feed efficiency affected by:
a. heredity (breed or strain of the animal)
b. environment (nutrition and management)
3. Reproduction
- nutrient requirement needed for:
a. female coming into estrus, subsequent conception and adequate development of the fetus until birth
b. males integrity of the reproductive organs and its sperm cells and sex hormones
- development of fetus (energy, CHON, Ca and P)
- severe deficiencies giving rise to low level of fertility by the following symptoms:
a. cessation of estrus
b. resorption of fetus
c. abortion
d. birth of dead or weak young
- principal nutrient deficiencies involved are protein, Ca, P and Vit. A
4. Milk production
- dairy type animals produce milk for human consumption and relatively very much less for the nourishment of their young
- temperate cows can yield 25-35 kg milk daily in 305 lactation period
- tropical cows can yield 8-12 kg daily
- genetics and climate (direct and indirect effects) have very much to do with this difference
- commercial dairying would generally need intensive grazing management or intensive forage production
- dairy cows need improved forages for efficient and economical production
- energy rather than crude protein seems to be the more critical problem in meeting adequate needs of the dairy cows in the Philippines
- concentrate would be needed to provide that energy deficit
- common rule of thumb, 1 kg of good concentrate mixture of every 2.5 kg of milk in excess of 5 kg if forage is of good quality
- milk constituents and blood sugars:
Casein ------------------------------------------------------ blood amino acids
Immune globulins ---------------------------------------- blood globulins
Fat ---------------------------------------------------------- fatty acids; acetate
Lactose ----------------------------------------------------- glucose
Minerals --------------------------------------------------- minerals in blood
Vitamins --------------------------------------------------- vitamins in blood
5. Egg production
- major factors affecting nutrient requirement :
1. rate of egg production
2. egg size or weight
3. egg shell thickness
4. body size of layer
- factors affecting egg shell quality is dietary calcium
- egg shell quality can be measured :
1. specific gravity of egg
2. shell thickness
3. shell smoothness
4. breaking strength
5. percentage of cracks or shell appearance
- low dietary calcium levels, less than 2 % decrease egg quality in chickens
Nutrition is the series of process by which an organism takes in and assimilates food for promoting growth and replacing worn-out or injured tissues.
A nutrient is any feed constituent or group of feed constituent of the same general chemical composition that aids in the support of life.
Digestion is the breakdown of feed particles into suitable products for absorption.
Absorption is the transfer of substances from GIT to the circulatory (blood or lymph) system.
A metabolism is the combination of anabolic and catabolic reactions occurring in the body with the liberation of energy.
Enzymes is a complex protein produced in living cells that causes changes in other substances within the body without being changed itself (organic catalysts).
Classes of nutrients
Water – the cheapest and most abundant nutrient. It makes up to 65-68 % of animal BW at birth and 45-60 % of BW at maturity.
- accounts 90-95 % of blood and many tissues contain 70-90 % water
- found in:
1. Intracellular water – mainly muscles and skin
2. Extracellular water – mainly interstitial fluids, blood plasma, lymph, synovial and cerebrospinal fluids.
- functions:
1. transport of nutrients and excretions
2. chemical reactions and solvent properties
3. body temperature regulation
4. maintain body cells
5. lubricates and cushion joints and organs in the body cavity
- deficiencies:
1. reduced feed intake and palatability
2. weight loss due to dehydration
3. increased secretions of N and electrolytes such as Na and K
Carbohydrates – made up of C (40 %), H (7 %) and O (53 %). It makes up approximately ¾ of plant dry weight and thus the largest part of animals food supply.
- formed by photosynthesis
- classification:
1. Monosaccharide – includes hexose (glucose, fructose, galactose) and pentose (arabinose, xylose, ribose)
2. Disaccharide – includes sucrose, maltose, lactose, cellobiose
3. Polysaccharide – includes starch (amylase, amylopectins, glycogen), cellulose, mixed polysaccharide (hemicellulose, pectin), and lignin
- functions:
1. source of energy
2. source of heat
3. building stores for other nutrients
4. stores in animal body by converting to fats
- deficiencies:
1. ketosis
2. diabetes mellitus
Fats (lipids or ether extract) – made up of C (77 %), H (12 %), and O (11 %). It is insoluble in water but soluble in organic solvents.
- fat will yield 2.25 times more energy than CHO or proteins
- classifications:
1. Simple lipids
2. Compound lipids – includes phospholipids (phosphoric acid and nitrogen), glycolipids, and lipoproteins
3. Derived lipids – includes fatty acids and sterols
- functions:
1. dietary supply
2. source of heat, insulation and protection for animal body
3. source of essential fatty acids (linoleic, linolenic and arachidonic acid)
4. serve as carrier for absorption of fat soluble vitamins
- deficiencies:
1. skin lesions, hair loss and reduced feed growth rate
2. ketosis (catabolism of body fat)
3. fatty liver (abnormal metabolism of liver)
Proteins – made up of C (53 %), H (7 %), O (23 %), N (16 %) and P (1 %). It is the principal constituents of the organ and sifts structures of the animal body.
- true proteins, composed of amino acids
- non-protein nitrogen (NPN), not true protein in nature but contain N and can be converted to protein by bacterial action, e.g. urea
- crude proteins (CP), composed of true proteins and any nitrogenous products (CP = % N x 6.25)
- protein quality refers to the amount and ratio of essential amino acids present in protein.
- classifications of proteins:
1. Simple (globular) proteins – yielding only amino acids or their derivatives upon hydrolysis, e.g. albumins, histones, protamines, globulins, glutelins, and prolamins
2. Fibrous proteins – constitute about 30 % of total protein in animal body, connective tissue, e.g. collagens, elastin, keratins
3. Conjugated proteins – a simple proteins are combined with non-proteins radical, e.g. nucleoprotein, glycoprotein, phosphoproteins, hemoproteins, lecithoproteins, lipoproteins, metalloproteins.
- functions of proteins:
1. basic structural unit of the animal body
2. body metabolisms
- classifications of amino acids:
1. Essential amino acids – those amino acids which are essential to the animal and must be supplied in the diet because the animal cannot synthesize them fast enough to meet its requirements. Examples: phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, histidine, arginine, leucine, lysine
2. Non-essential amino acids – those amino acids which are essential to the animal but are normally synthesized or sufficient in the diet and need not be supplement. Examples: alanine, asparagines, aspartic acid, cysteine, cystine, glutamic acid, glutamine, glycine, hydroxyproline, praline, serine, tyrosine
- deficiencies:
1. reduced growth rate and feed efficiency
2. anorexia
3. infertility
Minerals – are inorganic solids, crystalline chemical elements. It makes up 5 % of an animal body on dry weight basis.
- ash, total mineral content of plants or animals
- functions:
1. skeletal formation and maintenance
2. protein synthesis
3. oxygen transport
4. fluid balance (osmotic pressure)
5. regulating acid-base balance of enzyme systems
6. activators and/or component of enzyme system
7. mineral-vitamin relationship
- classifications:
1. Major mineral or macro minerals – normally present at greater level in animal body or needed in large amounts in the diet.
- examples:
a. Sodium and chlorine – for formation of digestive juices, control of body fluid concentration, control of body fluid pH, and nerve muscle activity.
deficiency:
• unthrifty appearance and impaired performance
• disrupted nerve and muscle function
• nervous prostrations
b. Calcium – for bone and teeth formation, nerve and muscle function, acid-base balance, and milk production and egg production
deficiency:
• rickets
• osteomalacia or osteoporosis
c. Phosphorus – for bone and teeth formation, component of protein in the soft tissues, milk production and egg production, and metabolic processes.
deficiency:
• rickets
• osteomalacia or osteoporosis
• poor appetite, slow gain, lowered milk production, low blood phosphorus and unthriftiness
• animal may eat soil and chew on nonfeed objects
d. Magnesium – necessary for many enzyme systems, play as a role in CHO metabolisms, and necessary for the proper functioning of the nervous system.
deficiency:
• hypermagnesemic tetany – hyper-irritability of neuromuscular system producing hyperexcitability, incoordination and frequently death
e. Potassium – for osmotic pressure, acid-base balance, rumen digestion, and intracellular cation in neuromuscular activity
deficiency:
• decreased feed consumption
• lowered feed efficiency
• slow growth
• stiffness
• emaciation
f. Sulfur – for component of the amino acid (cystine and methionine) and vitamins (biotin and thiamine), synthesis of sulfur containing amino acids in the rumen, and the formation of various body compounds
deficiency:
• protein deficiency – general unthrifty conditions and poor appearance
2. Minor/trace or micro minerals – normally present at low levels in animal body or small amount in the diet.
- examples:
a. Iron – necessary for hemoglobin formation, essential for the formation of certain enzymes related to oxygen transport and utilization, and formation of certain compounds which serve iron stores in the body, e.g. ferritin (found primarily in the liver and spleen) and hemosiderin (found mainly in the blood)
deficiency:
• low blood hemoglobin
• labored breathing
• listlessness
• pale eyelids, ears and nose
• flabby, wrinkled skin
• edema of head and shoulder
b. Iodine – for production of thyroxine by the thyroid glands.
deficiency:
• goiter at birth or soon thereafter
• dead or weak at birth
• hairlessness at birth
• infected navels esp. foals
c. Cobalt – for component of Vit. B12 molecule and rumen synthesis of Vit. B12.
deficiency:
• poor appetite
• unthriftiness
• weakness
• anemia
• decreased fertility
• slow growth
• decreased milk and wool production
d. Copper – for iron absorption, hemoglobin formation, synthesis of keratin for hair and wool growth, and various enzyme systems.
deficiency:
• low blood and liver copper
• bleaching of hair in cattle
• abnormal wool growth in sheep
• abnormal bone metabolism
• muscular incoordination
• weakness at birth
• anemia
e. Fluorine – for reduces incidence of dental caries, and retards osteoporosis in mature animals.
deficiency:
• excessive dental caries esp. children
f. Manganese – for influencing estrus, ovulation, fetal development, udder development, milk production, and growth and skeletal development.
deficiency:
• delayed estrus
• reduced ovulation
• abortions
• resorptions
• deformed young
• poor growth
• lowered serum alkaline phosphates
• lowered tissue manganese
• knuckling over in calves
g. Selenium – for Vit. E absorption and utilization, component of enzyme (glutathione peroxidase – destroy toxic peroxide in the tissues thereby having a sparing effect in the Vit. E requirement), and maintenance of normal cell functions and membrane health.
deficiency:
• muscular dystrophy (white muscle disease)
• retained placenta in cows
• heart failure
• paralysis
• poor growth
• low fertility
• liver necrosis
• pancreatic fibrosis in chicks
h. Zinc – prevents parakeratosis, promotes general thriftiness and growth, promotes wound healing, related to hair and wool growth and health, and deficiency impairs testicular growth function.
deficiency:
• parakeratosis
• general thriftiness
• poor growth
• unhealthy looking hair or wool
• slow wound healing
Vitamins – is organic components of natural food. It is present in foods in minute amounts and effective in small amounts. It is also essential for development of normal tissue necessary for metabolic activity but do not enter into structural portion of the body. Other function is necessary for growth and maintenance.
- cannot be synthesized by the animal
- related substances:
1. Provitamins or precursors (carotene)
2. Antivitamins, vitamin antagonists or pseudovitamins
- 2 forms of vitamins:
1. Fat-soluble vitamins – can be dissolved in fats
a. Vitamin A – is also known as retinol. It promotes the development of visual pigments. It is indispensable for the formation of epithelial tissues and improves the resistance to infection.
b. Vitamin D – also known as calciferol. It regulates the incorporation of Ca and P into the bone matrix and the Ca absorption from the intestinal lumen.
c. Vitamin E – also known as tocopherol. It works as a biological antioxidant (detoxifying agents). It participates as a component of the respiratory chain and function in nucleic acids metabolisms and in endocrine glands.
d. Vitamin K – also known as menadione. It functions in the blood coagulation system. It acts in the maturation of the bone structure.
2. Water-soluble vitamins – can be dissolved in water
a. Vitamin B1 – also known as thiamin. It participates in the process of carbohydrate metabolisms.
b. Vitamin B2 – also known as riboflavin. It acts in the respiratory chain as a constituent of the flavin enzymes concerned with H transfer.
c. Vitamin B6 – also known as pyridoxine. It is active in amino acids metabolisms as a coenzyme of several enzyme systems.
d. Vitamin B12 – also known as cyanocobalamin. It is essential in the reduction of one carbon compounds in the fat and protein metabolisms.
e. Biotin – also known as Vit. H. It is necessary for gluconeogenesis and fatty acid synthesis where it acts in carboxylation reactions.
f. Folic acid – it acts in the one carbon metabolisms where it is indispensable in the formation of amino acids and nucleic acids.
g. Nicotinic acid – also known as niacin or nicotinamide. It acts as an active group of different coenzyme which is related to the citric acid cycle.
h. Pantothenic acid – part of coenzyme A which occupies a central position in the intermediary metabolisms by activating weakly active acids.
i. Vitamin C – also known as ascorbic acid. It is essential in the formation and maintenance of skeletal tissues. It participates as an oxidation-reduction system in cellular oxidation processes and also involved in defensive mechanisms.
- vitamin deficiency in poultry:
1. nervous disorders such as convulsions
2. skin or mouth lesions
3. discharge from eyes or swollen, pasted eyelids
4. reduced resistance to infectious diseases
5. poor feathering
6. bone abnormalities
7. leg weakness or paralysis
8. egg production reduced or below full potential
9. retarded growth
10. hatchability reduced or below full potential
- vitamin deficiency in pigs:
1. muscular incoordination of other nervous signs
2. reduced feed intake
3. impaired vision or blindness
4. scours and/or vomiting
5. hair, skin and claw problems
6. anemia
7. impaired feed conversion
8. lameness or unsteady gait
9. poor reproduction
10. retarded growth
11. weakness or increased mortality of newborn pigs
- vitamin deficiency in ruminants:
1. muscular incoordination or other nervous signs
2. reduced feed intake
3. impaired vision or blindness
4. digestive disturbances
5. rough hair coat
6. degeneration of heart and skeletal muscle
7. poor reproduction
8. retarded growth
9. bone deformities or swollen joints
Unit 4: Digestive Systems and Absorption of Food Nutrients
The digestive system consists of the teeth, mouth, gullet (esophagus), stomach, liver, intestine, pancreas, and rectum.
Digestion begins in the mouth where feed is broken down into small pieces by the teeth and mixed with saliva before being swallowed.
In the stomach feed is mixed with the juices to form a soft paste. This then passes into the intestine where bile from the liver and juices from the pancreas are added. The action of these juices is to break down the feed and allow the nourishment it contains to be absorbed by the blood in the walls of the intestine. Waste matter collects in the rectum and passes out of the body through the anus (or cloaca in birds).
Splanchnology is the name of the study of digestive system.
Animal’s carnivore, omnivore and herbivores
Animals are divided into three groups:
Carnivores which eat meat, e.g. dog, lion
Omnivores which eat meat and plants e.g. pig
Herbivores which eat plants e.g. cow, horse
The digestive system of omnivores and carnivores is as described above. In herbivores the digestive system is very large because they eat large amounts of grass.
- The horse, donkey and mule are herbivores but do not chew the cud. They are non-ruminants.
- Cattle, goats, sheep and buffalo chew the cud. They are ruminants.
Digestion – includes 2 processes the mechanical process and chemical process. The mechanical process includes chewing (mastication) and muscular contractions of the GIT. The chemical process involves the action of acids in the GIT or enzymes produced by the microorganisms located in various parts of the GIT.
- types of GIT:
1. Non-ruminant or simple stomach
2. Ruminant or compound stomach
3. Avian type or modified-simple stomach
Non-ruminant
- includes the pigs, horse, rabbit, dog and cat and humans
- major parts includes the mouth, esophagus, stomach, small intestine, large intestine
Mouth – consists of tongue (grasping food), teeth (mastication of food), and salivary gland (produce saliva which contains water to moisten food, mucin to lubricates food for easy swallowing, bicarbonates salts to buffer or regulate pH and salivary amylase to start CHO digestion).
Esophagus – a muscular tube. It allows passage of food from mouth to stomach.
Stomach – a muscular digestive organ. It is for storage of ingested feed, mechanical breakdown, and production of HCl, enzymes and mucus.
- 3 regions:
1. Cardiac – cells produce mucus that protects the stomach lining.
2. Peptic – cells produce HCl, pepsin (proteolytic enzyme) and mucus.
3. Pyloric – mucus producing cells.
Small intestine – has 3 divisions, namely:
1. Duodenum – first section that is very active site of digestion that receives secretions from pancreas, liver, and intestinal walls.
2. Jejunum – middle sections that involved in nutrient absorption.
3. Ileum – last section that also involved in nutrient absorption.
Large intestine – has 3 sections, namely:
1. Cecum – first section that is large in horse and rabbit and well developed as in the horse that contains many bacteria which produced enzymes that digest fiber.
2. Colon – middle section that involved in reabsorption of water.
3. Rectum – last section
Ruminants
- includes the cattle, sheep, goat and carabao
- 4 compartment stomachs:
1. Rumen – large muscular compartment which fills the left side of the body cavity. It is also called paunch.
- has papillae that covered by projections for absorptions of nutrients
- provide favorable environment for protozoa and bacteria
- pregastric fermentation produces enzymes that breakdown fiber as well as starch and protein, and volatile fatty acids (VFA) such as propionic acid, butyric acid and acetic acid.
- water soluble vitamins and vitamin K
- bacterial synthesis of amino acids and protein
- favorable conditions:
a. anaerobic environment
b. constant warm temperature
c. moisture
d. constant food supply
e. mixing
f. removal of toxic end-products
- additional functions:
a. storage
b. soaking
c. physical mixing and breakdown
2. Reticulum – also called honeycomb. The main function is to move food into the rumen or omasum and collect of dense particles of food and in regurgitation of ingesta during rumination.
- rumination, movement of ingesta back up the esophagus to the mouth for additional mechanical breakdown (chewing the cud)
3. Omasum – is a round muscular organ which contains many muscular laminae. It is also called many fold or many plies.
- functions:
a. controlling passage of ingesta to lower tract (act as pump)
b. reduce particles size of ingesta
c. absorption
4. Abomasums – also called as true gastric stomach. It is identical to the gastric stomach of non-ruminants.
- small intestine and large intestine is similar in form and functions as in the non-ruminants
- additional features in ruminants:
1. Esophageal groove – found at the base of the esophagus and when stimulated by sucking forms a tube which empties into the abomasums. The main function is to direct milk obtained from sucking to escape microbial digestion in the rumen.
2. Rumination – described as controlled vomiting. It is control set of contractions of esophagus, reticulum, and rumen that allows ingesta to be swallowed regurgitated back up to the esophagus where fluids swallowed again. It has additional remastication and reswallowing of solids.
3. Eructation – belching of gas. It is removal of large volumes of gas produced in the rumen. It is contractions of the upper part of the rumen force the gas up the esophagus and from there the gas penetrates into the trachea and lungs.
When the ruminant has finished eating, the food is brought back up and rechewed. This is called chewing the cud or rumination. If the animal stops ruminating this is a sign of ill health.
Ruminants make a lot of gas in their stomachs and belch once every minute, (unlike people they belch silently). If the belching stops the stomach swells with gas. We call this bloat or tympany.
The rumen moves regularly and contracts about once every minute. By putting your fist on the left flank (in the hollow behind the ribs) you will be able to detect the contractions. Regular contractions are a sign of good health.
Avian type
– consists of beak, crop, proventriculus, ventriculus, small intestine and large intestine, e.g. all birds.
Beak – collects particles of feed and breaks some large particles into smaller pieces. The tongue and salivary glands are present and saliva does not contain salivary amylase.
Crop – enlarged area that connected to the esophagus. The functions are for temporary storage and moistening of food, place for salivary amylase to work, and microbial fermentation in some species.
Proventriculus – true stomach of birds. It is the site of HCl and pepsin production. The ingesta pass through the proventriculus very rapidly (14 seconds).
Ventriculus – commonly called gizzard. It is muscular area that contains grit. The muscular contractions which are involuntary aid in the mechanical breakdown of food and it is similar to the mastication by the teeth in the non-ruminant and ruminant.
Small intestine – it is similar to the small intestine of the non-ruminant and ruminant.
Large intestine – has 2 areas (called ceca) which are very similar in form and function to the cecum of non-ruminant and ruminants.
The bird has no teeth, food is swallowed whole and goes into the crop where it is stored and mixed with saliva. If you feel the crop you can tell if a bird has been feeding or not.
The feed passes from the crop into the stomach where it mixes with the juices before passing into the roundish, thick walled, muscular organ called the gizzard. The gizzard contains small stones which the bird has eaten to help the gizzard to grind up the food for digestion. Nutrients are absorbed as ground up feed passes along the intestine.
Birds do not produce liquid urine. Waste from the kidneys forms a thick white material which is mixed with the feces (droppings). Both are then passed out through the cloaca. The duck produces wetter droppings than the chicken.
Nutrient digestion
Nutrient Basic unit
Protein ---------------------------------------------------------- amino acids
Starch -------------------------------------------- glucose (non-ruminant), VFA and lactic acid (ruminant)
Cellulose ------------------------------------------------------- VFA
Sucrose -------------------------------------------------------- glucose and fatty acids
Lactose ------------------------------------------------------- glucose and galactose
Lipids ---------------------------------------------------------- fatty acids and glycerol
Minerals ------------------------------------------------------- any soluble form
Vitamins ------------------------------------------------------- any soluble form
End products of enzymes
1. Saliva
- salivary amylase, starch to maltose
2. Rumen
- microbial cellulose, cellulose to VFA
- microbial amylase, starch to VFA and lactic acid
- microbial proteases, protein to amino acids and NH3
- microbial urease, urea to CO2 and NH3
3. Stomach, abomasums, proventriculus
- pepsin, protein to polypeptides
4. Pancreas
- trypsin, protein to peptides and amino acids
- chymotrypsin, protein to peptides and amino acids
- carboxypeptidase, protein to peptides and amino acids
- amylase, starch to maltose
- lipase, lipids to fatty acids and glycerol
5. Small intestine
- aminopeptidase, protein to peptides and amino acids
- dipeptidase, peptides to amino acids
- maltase, maltose and glucose
- lactase, lactose to glucose and galactose
- sucrase, sucrose to glucose and fructose
Absorption – occurs primarily in small intestine.
- villi, small projections which line the small intestine
- papillae, projections which line the rumen (VFA)
- occurs as the result of diffusion or active transport
- diffusion, movement of the basic units from areas of high concentration (GIT) to area of lower concentration (blood)
Metabolisms – occurs only after basic units of nutrients have been absorbed into the blood. The chemical reactions performed by the cells to use the basic units of the nutrients for their specific functions (glucose – for energy and amino acids – for protein synthesis).
- reactions functions in series and are described as pathways or cycles:
1. Embden myerhof pathway of glucose metabolisms
2. Krebs cycle
- has two forms:
1. Anabolisms – building up of tissues
2. Catabolism – breaking down of tissues
Unit 5: Ration Formulation
Feeds – naturally occurring ingredients in the rations of animals that are used to sustain life.
Classification of feeds
1. Roughage – livestock feeds that contain more than 18 % crude fiber when dry.
- examples:
a. hay
b. silage
c. pasture
d. fodder
2. Concentrates – livestock feeds that contain less than 18 % crude fiber when dry.
- examples:
a. meat scraps
b. meat and bone meal
c. fish meal
d. blood meal
A ration is the amount of feed given to an animal to meet its needs during a twenty-four hour period.
A balanced ration is one that has all the nutrients the animal needs in the right proportions and amounts.
Ration formulation is a process of combining different feed ingredients to a proportion that will give the animals the proper amount of nutrients needed at their particular stage of production.
Important consideration in feed formulation
1. acceptability
2. digestibility
3. cost
4. presence of anti-nutritional factors and toxins
Methods of ration formulation
1. Pearson square method
2. Simultaneous equation method
3. Two-by-two matrix method
4. Trial-and-run method
5. Linear programming
Pointers in ration formulation
1. listing of nutrients requirements of animals
2. nutrient analyses of feed ingredients and cost to be used
3. usage and limitation of feed ingredients
4. check ration for each nutrient content cost/kg of mixed feed
Ration functions
1. Maintenance
- feed/ration or nutrients for the following purposes:
a. maintain BW or size
b. support essential life processes
c. maintain body temperature
d. maintain the different body secretions
- basal metabolisms or fasting catabolism, minimum energy expenditure to maintain essential life processes.
- energy requirement for maintenance is related to the body surface are or metabolic body size.
- activity increment, energy expenditure due to normal body movements and associated activities.
- protein requirement for maintenance is made up of two portions:
a. Endogenous urinary nitrogen (EUN) – normal wear and tear of the body organs and tissues
b. Adult growth functions – feathers, hairs, hoofs, nails
2. Growth
- correlated increase in the mass of the body to reach the size at maturity fixed by heredity.
- reflected in increased weight and size
- characterized by:
a. increase in the number of cells
b. increase in size of the cells
- optimum growth is in high protein level and good protein quality (essential amino acids)
- energy (CHO, fats, CHON) is the driving force for tissue synthesis or anabolisms
- high energy ration will make it faster and shorten the feeding or growth period
- low energy ration will slow down the growth rate and thus lengthen the growth rate
- ways of energy restrictions:
a. limit the total feed intake
b. lower the energy content or density of the ration
- energy to protein ratio is an important factor in the efficiency and economy of growth
- measures by the average daily (ADG) and feed efficiency affected by:
a. heredity (breed or strain of the animal)
b. environment (nutrition and management)
3. Reproduction
- nutrient requirement needed for:
a. female coming into estrus, subsequent conception and adequate development of the fetus until birth
b. males integrity of the reproductive organs and its sperm cells and sex hormones
- development of fetus (energy, CHON, Ca and P)
- severe deficiencies giving rise to low level of fertility by the following symptoms:
a. cessation of estrus
b. resorption of fetus
c. abortion
d. birth of dead or weak young
- principal nutrient deficiencies involved are protein, Ca, P and Vit. A
4. Milk production
- dairy type animals produce milk for human consumption and relatively very much less for the nourishment of their young
- temperate cows can yield 25-35 kg milk daily in 305 lactation period
- tropical cows can yield 8-12 kg daily
- genetics and climate (direct and indirect effects) have very much to do with this difference
- commercial dairying would generally need intensive grazing management or intensive forage production
- dairy cows need improved forages for efficient and economical production
- energy rather than crude protein seems to be the more critical problem in meeting adequate needs of the dairy cows in the Philippines
- concentrate would be needed to provide that energy deficit
- common rule of thumb, 1 kg of good concentrate mixture of every 2.5 kg of milk in excess of 5 kg if forage is of good quality
- milk constituents and blood sugars:
Casein ------------------------------------------------------ blood amino acids
Immune globulins ---------------------------------------- blood globulins
Fat ---------------------------------------------------------- fatty acids; acetate
Lactose ----------------------------------------------------- glucose
Minerals --------------------------------------------------- minerals in blood
Vitamins --------------------------------------------------- vitamins in blood
5. Egg production
- major factors affecting nutrient requirement :
1. rate of egg production
2. egg size or weight
3. egg shell thickness
4. body size of layer
- factors affecting egg shell quality is dietary calcium
- egg shell quality can be measured :
1. specific gravity of egg
2. shell thickness
3. shell smoothness
4. breaking strength
5. percentage of cracks or shell appearance
- low dietary calcium levels, less than 2 % decrease egg quality in chickens
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