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