Dairy Flashcards
Milk Composition
● Water – 87.8%
● Butterfat – 3-4%
● Protein – 3.2%
● Lactose – 4.7%
● Minerals (calcium, magnesium, phosphates) – 0.8%
Proteins in milk
Casein and whey
Suspensory ligament
A supporting or holding ligament
Milk let down
Cows Teats are stimulated by milking machine, sends a message to brain.
Pituitary gland produces oxytocin which travels through blood to udder
Prolactin and oxytocin control milk synthesis and trigger milk let-down.
Oxytocin travels into the blood in the alveoli cells, where it initiates milk let down and causes muscles around alveoli to contract , forcing milk out teats.
- If cow disturbed during milking , she releases adrenaline , which stops oxytocin and therefore the milk letdown process. Routine important to prevent adrenaline release.
Liquid milk production
Constant milk supply all year round.
Milk Price per payment
(A x protein % + B x butterfat %) – C
A = set value for protein
B= set value for fat
C = processing charge based on volume component of milk and cost of collection and transport. Usually constant
TBC
Total bacteria count
Total number of living bacteria per ml of milk
SCC
Somatic cell count
Mainly the numbers of white blood cells. High numbers of these cells in milk are an indicator of mastitis in the herd
Milking interval
Is the time between successive milking. Most farmers operate a 14:10 hour or a 13:11 hour interval.
Residual milk
Milk that remains in the udder after the bulk of the milk has been removed during milking.
Withdrawal period
The minimum time that must elapse after the last administration of a drug (e.g. antibiotics) for the treatment of an illness in an animal, before that animal or its products (e.g. milk) can be used for human consumption.
Withdrawal periods prevent any residues of the drug being present in the animal or its
products.
Milk Composition Test
The percentage fat, protein and lactose in the milk are determined for payment purposes
TBC test
Indicator of hygiene on the farm. total number of living bacteria per ml is counted.
Should be under 100,000 per ml
High TBC caused by mastitis, dirty milking machines , not changing milk filter.
Reducing TBC
- Change milk filter to reduce debris content
- Clipping of tails to keep teats & udder clean
- Change liners of milk clusters twice a year to prevent build up.
SCC test
This test is an indicator of udder health. Somatic cells are W.B.C’s that occur naturally in milk, no. increases if udder has mastitis.
SCC should be below 400,000 per ml
High SCC affects the processing of the milk.
Reducing SCC
- Lime on cubicles to kill bacteria under cow’s udder
- Milk infected cows last to prevent transfer of disease to other cows and disinfect clusters.
- Teat dipping in antibiotic solution prior & post milking
- Cull old cows with high SCC to prevent spreading.
Antibiotic test
This is the first test carried out by all milk processors. Antibiotics must be absent from all milk as could contribute to antimicrobial resistance.
Delvo-test : colour change from purple to yellow = positive result.
Excess water test
Milk processors monitor milk for the addition of water by checking the freezing point of the milk. The addition of the water will change the freezing point of milk.
- Illegal to add water to increase yield.
- Decreases composition of SNE & fats
Resazurin test
Blue dye that investigates the quality of a milk sample. Resazurin is incubated with the milk sample at 37°C for 15 mins. It undergoes a colour change depending on the number of bacteria present. A blue colour indicates excellent quality and a white colour indicates poor quality
EBI
Economic Breeding Index
Is a single figure profit index given in euros of profit per lactation for the animal’s progeny compared to an average dairy cow.
Sub-indexes:
● Production
● Fertility
● Calving
● Maintenance
● Management
● Beef
● Health
Calf
Birth - 9 months
Heifer
A female that hasn’t had a calf
Steer/bullock
A castrated male
Mastitis
An inflammation of one or more of the quarters of the udders caused by a bacterial infection
British Friesian
Dual purpose breed
Milk yield of 6600 litres.
Jersey
Produces milk high in protein and fat
Lower yield - 5500 litres
Easy calving
High fertility
Resistance to lamness and longevity
Jersey X Holstein Friesian
- Smaller in size
Low milk yield – 5272 litres
High butterfat and protein content
Bovine Viral Diarrhoea (BVD)
Is a disease caused by a virus. There is a compulsory testing programme in Ireland to identity calves born with the disease. There is an eradication scheme
to eliminate this disease so calves tested positive for the disease are culled.
Colostrum
First milk produced by mammals. It is full of nutrients and antibodies.
Weaning
The process of changing a young animals diet to other food (concentrates and
other feeds) while withdrawing the supply of its own mothers milk.
Reasons for culling
- Age
- Health problems
- Problems with milk production
- Problems with fertility
- Grading up the herd
BCS
Body Condition Score
The ration of lean mean to fat. Scored from 1 to 5. 1 meaning extremely thin
animal. 5 meaning extremely fat.
BCS at drying off – 3.0
BCS at precalving – 3.25
BCS at mating - 2.9
Selecting replacement heifers
BCS of 3.25 at mating
Good teeth and feet and well developed udder with 4 teats of uniform size.
Good udder conformation
Be free of disease
Come from a mother with high percentage of fat and protein in milk
Come from a mother that has good fertility and easy calving
Good temperament
Biosecurity
Measures that a farmer should take to prevent entry of disease to their farm.
Lactation period
The length of time (days) following birth that a cow produces milk , 305 until drying.
Early 0-3 months
Mid 4-7 months
Late 7-10months
Length of cycles & periods
Length of oestrous cycle – 21 days
Duration of oestrus – 18 to 24 hours
Gestation period – 283 days (9.5 months)
Lactation period – 305 days
Dried off – 60 days
Calving interval – 365 days ideally.
‘Milking off her back’
After calving a dairy cow will lose weight as her feed intake doesn’t meet her energy output. The cow will make up the deficit in energy by using up some
of her energy reserves.
Heat detection aids
A device that helps to conform or identify a cow when she is in heat. E.g. tail painting, kamar device, activity meter, chin ball.
Heat detection aids
A device that helps to conform or identify a cow when she is in heat. E.g. tail painting, kamar device, activity meter, chin ball.
Persistency
Rate at which the milk yield falls after the peak yield is reached.
Lactation Curve
Curve that plots milk production of a dairy cow over the couse of lactation until she is dried off.
Peak yield = day 70 after calving
Creamery Farm / Manufacturing Milk Production
- Spring calving, break in milking (dec-Jan) , produce milk between spring & autumn when can take advantage of grass.
- dairies pay for quality of milk and the fat % , Protein % don’t want quantity
- Jersey cow / hybrid vigour
- A.I selected for kg of solids yield
- bull calves used in beef trade
- Cows dried off in winter months
- Produces butter , yogurt , cheese
Liquid Farm
Year round calving,
- constant milk supply
- dairies pay for quantity not quality , paid flat rate over the winter months regardless of SNL % of milk.
- holstein Frisian
Cows AI selected for milk yield
Bull calves used for milk yield.
Cows not dried off over winter months
Drying off
The period of time the cow is not producing milk = 60 days
- ADVS : Allows repair of udder tissue, development of unborn calf , builds up BCS and energy , allows a production of colostrum & replenishment of minerals
- MANAGEMNT : Assessment of BCS , apply appropriate feeding regime , dry cow mastitis treatment , vaccinations & dosing
SNF
Solid - non fat ; Lactose , protein , minerals
Factors that affect milk composition
Cow breed : Holstein Friesian (quantity) / Jersey cow (high levels of SNF)
Age : The older the cow , the more milk composition will decrease.
Lactation : Fat & Protein content decrease as milking season progresses but rises again at the end of lactation
Milking Interval : Longer Interval = Lower fat % , 12 hours ideal.
Cow’s health : Mastitis , milk composition suffers due to W.B.C’s increase
Animal Feed : Fibre increases acetate fat levels , good grassland increases protein.
Total Milk Yield
Lactation X 200 = Average
Lactation X 220 = High
Mastitis
Infection of udder
Caused by bacteria
Symptoms : Swollen udder, clots in milk , high SCC
Treatment : Antibiotics
Prevention : Keep milking parlour clean
limit negative Energy Balance in early lactation
Good Quality grass feed 72% silage + DMD
Zero grazing , limits movement to store energy
Correct BCS at calving
Implication of negative energy balance for cow
Cows reproductive cycle may not start since calving , not ovulating causing longer calving interval. Reduces production efficiency.
Steaming up
Last 10 weeks of pregnancy
- Increases cow development
- Increases colostrum quality & production
- Ensures maximum milk yield during lactation.
Calf Prep
- Records of mating / A.I to be kept to predict calving dates.
Isolate cow from herd
Ensure a vet is on-call if needed
Have an experienced person on hand & calving jack nearby.
Once Calf is born :
Clear mucus from nose and mouth (opens airways)
- Allow the cow to lick calf to stimulate circulation (or rub vigorously with straw)
- Dip navel in iodine to prevent infection
- Feed calf 3L of colostrum within the first 12 hours
- Calf tagged for identification and traceability.
Calf Management
First 3 days : Indoors in disinfected, well ventilated , dry straw bed , separate pen from the rest of the herd , first 3 L of colostrum and then whole milk.
Weaning : after 5 days to 1 week , move into group housing , fed on whole milk 2x a day. Concentrates introduced at 1 week to develop rumen.
6-8 weeks weaned off milk and eating 1KG hay & concentrates . Then left out on grass, weather permitting (leader - follower system)
Colostrum
6.7% Fat , protein 14.9 % , Lactose 2.5%
- Contains large amounts of antibodies that protect the calf against disease ,
- important as calves have no immune system also acts as a laxative to help clean out calves digestive system.
- High in protein for increased growth.
- High in fat for insulation or vitamins for body processes
Early lactation Management for Cow
- Fed on a high plane of nutrition
- Mineral supplements to prevent grass tetany & milk fever
- Grass growth slow , concentrate feeding should be maintained .
Tail Painting
Top of cows tail is painted when she is in heat she is mounted by another bull which rubs off the paint
Kamar Device
Pressure Sensitive chamber which contains a dye , attached to top of tail , when mounted chamber bursts
Chin Ball
Attached to a vasectomised bull , will mark the cows in eat without fertilising them
Replacement Heifers
Females reared to be used as replacements for breeding cows in the herd.
- Allow farmers to maintain & expand herd size
- Teagasc recommends annual replacement of 17 %
- Rear our own replacement heifers to maintain closed herd & prevent entrance of disease.
Selecting a replacement heifer
Maternal line - desirable maternal traits relating to milk production, quality and fertility & calving.
BCS of 3.25 (required at mating )
Healthy Udder - (4 teats) , impacts ease of milking & production efficiency.
Breed - Suitable genetics for the farm , could increase the genetic merit of the herd.
Bull selection
Important that farmers select an ‘easy’ calving bull for first-time heifers.
- Cows should be mated with high EBI sires
- Select through A.I unless stock bull has a high EBI to improve genetic merit.
Why should colostrum be fed to calves within 4 hours of birth
- Colostrum quality decreases (3.7 %) every hour after birth
- A calfs ability to absorb antibodies directly into bloodstream decreases with time.
Why is dried colostrum not as effective as colostrum from calf’s mother
Doesn’t contain antibodies to diseases present on the farm.
Explain why good hygiene is essential in harvesting colostrum
- Prevent bacteria multiplying
- Antibody levels decrease
- Prevent bacteria entering udder
- Prevent microbial infection in the calf.
Advantages of feeding transition milk to replacement heifers
- Increased energy to support metabolism = stronger calf & high protein levels for increased growth rate, less concentrates required.
- good animal health
- Better development of digestive tract
- More nutrition then powdered milk
Aspects of sheds to make suitable for calves
High roof = good airflow ventilation
Board or concrete walls ensuring pen is draft free
Large area with adequate lying space
long feed barrier = adequate feeding space
roof lights = plenty of natural light.
Advantages of a grass fed system in a dairy enterprise
- healthier for animal health & welfare
- More natural method of feeding for animals
- Better quality of food entering food chain
- Products such as butter have a better taste - creamy
Artisan Food
- Food or drink made in a traditional manner using high-quality ingredients.
Challenges facing farmers with sustainable intensification on a dairy farm
-Capacity of a farm to produce fodder, may have to import feed for herd which impacts the sustainability of farm.
- Reducing the environmental impact of intensification
- Increased slurry , silage effluent and dairy washings more storage required to use all slurry produced on the farm , prevent run-off , low emission slurry spreading to reduce amt of ammonia emissions being lost & more productive land.
- Ability to find market for fairy bull calves and extra labour required for milking , calving and livestock management
Value added
Changing / processing a product from its raw state to a more valuable state.
How to increase fat & protein contents in milk
- Breeding high EBI cows
- Clover in sward
- Good quality silage (72-75% DMD) will increase milk solids
- Cross breed with jersey cows to increase milk solids = hybrid vigour
How to increase fat & protein contents in milk
- Breeding high EBI cows
- Clover in sward
- Good quality silage (72-75% DMD) will increase milk solids
- Cross breed with jersey cows to increase milk solids = hybrid vigour
Reason for negative energy balance in early lactation
Daily requirement of a cow cannot be met by the energy she consumes (cows cannot physically eat enough to meet the demands of lactation) so cow’s off her back
Feeding regime for mid-lactation
In mid lactation cows can produce milk on a grass-only diet , rotational grazing keeps highly digestible grass fed to the cows at all times, no requirements for concentrates at this stage.
Importance of “drying off”
Allows repair of udder tissue
- development of unborn calf
- production of colostrum
- Avoids calving difficulty or cow regains body condition
- allows milk reserves to be built up
- minerals replenished
Digestible energy
The gross energy minus the amount of energy digested in the faeces
Metabolisable energy
The digestible energy minus the energy lost in the form of methane gas and urine
production Diet
The extra amount of feed to produce 1KG of LWG or to produce a calf
Maintenance Diet
The amount of feed that allows an animal to maintain good health and condition with no loss or gain in weight.
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