LANGHILL MILK PRODUCTION

Question 1

What is the system Langhill farm for milking parlour?

What is the benefit of this type of parlour?

Answer 1

28:28 Herringbone parlour;
w/ large bore pipeline & milk flow meters

Benefit: gives milker easy access to the udders at a good working level

Question 2

How does Langhill ensure the Bactoscan of the milk is as low as possible?

Answer 2

• The milk is immediately pre-cooled through a heat exchange unit before entering the refrigerated bulk tank, to be cooled the last few degrees to 4 degree Celsius

Question 3

What are the purposes of fore-milking strips?

Answer 3

• To identify clinical mastitis
• Clears out teat canal (possibly reduces bactoscan)
• Stimulate milk let-down

Question 4

What is the purpose of keeping cows standing for 20 mins after milking?

Answer 4

To allow teat canals to close

Question 5

Describe the Langhill milking routine.

Answer 5

• 14 cows enter one side of the parlour
• Cows are automatically identified by electronic collars, (as they pass through a blue archway which contains a receiver that identifies each cow) which then activate the pre-determined amount of dairy concentrate to be dispensed into each feed trough
• Foremilk strip
• Clean teats w/ a handheld rotating brush
• Attach cluster
• Cluster removed
• Post-milking teat disinfection
• Stand cows for 20 mins

Question 6

What is the function of a dump bucket?

Answer 6

Collect milk which must not enter the bulk milk tank

- usually either colostrum or milk containing antibiotics

Question 7

What are the criteria to ensure the farm does not fail the antibiotic test?

Answer 7

• Cows being treated w/ antibiotics must be clearly identified (tail / leg tapes, computer Id, marker sprays)
• Accurate records must be kept
• Withholding times adhered to
• Good staff communication
• Mastitic milk should not be fed to calves

Question 8

What happens if the temperature of the milk is above 7C?

Answer 8

The milk flow meter will stop automatically and the milk will not be uplifted until it has been cooled properly to 4C.

Question 9

It is the responsibility of the tank driver to take a milk sample from the bulk tank at each collection. How many of these daily samples are tested each month?

Answer 9

4 samples

Question 10

What are tested in the 4 daily samples?

Answer 10

• Butterfat %
• Protein %
• Bactoscan
• Somatic cell count
• Antibiotics
• Extraneous water

Question 11

List the criteria for the items tested in the milk samples.

Answer 11

Butterfat%: Standard 4% (min acceptable 3.5%)

Protein%: Standard 3.3% (min acceptable 2.9%)

Bactoscan: Premium paid if below 30000/ml (penalties if >50000)

Somatic cell count: Premium paid below 200000 cells/ml (penalties if >250000/ml)

Antibiotics: Financial penalties if detected

Extraneous water: detected by freezing point depression

Question 12

How is the milk price of each month calculated?

Answer 12

The average of 4 weekly samples for butterfat% and protein% is calculated, which determines the basic milk price, then financial premiums or penalties for Bactoscan and somatic cell count are applied.

Question 13

How does the somatic cell count (SCC) indicate milk quality?

Answer 13

• The majority of the somatic cells are leukocytes (WBC), which become present in increasing numbers in milk usually as an immune response to a mastitis-causing pathogen
• A small number of epithelial cells, which are milk-producing cells shed from inside of the udder when an infection occurs

Question 14

What does each of the following SCC indicate:

Answer 14

SCC of 100,000 or less = indicates an uninfected cow, where there are no significant production losses due to sub-clinical mastitis

SCC of 200,000 = threshold value, determines whether a cow is infected with mastitis;

SCC of >200,000 = highly likely to be infected on at least 1/4

SCC of 300,000 or greater = cows infected with significant pathogens

Question 15

What is the trend in changes for SCC in milk.

Answer 15

SCC in milk increases after calving when colostrum is produced before the cow settles into lactation, and tend to rise towards the end of lactation, most likely due to the concentrating effect of lower amounts of milk being produced

Question 16

What is the SCC deemed unfit for human consumption by the European Union?

Answer 16

> 400,000

Question 17

What does low SCC indicate?

Answer 17

• Could be a sign of poor immune response but not necessarily true
• Could be simply a low level of current infection
• Immune response is best measured by how quickly the immune system reacts to the disease challenge , not how many WBC are present before infection occurs

Question 18

What does bactoscan indicate?

Answer 18

The level of bacterial contamination from external sources e.g. insufficient cleaning of the milking equipment / poor udder and teat preparation prior to milking, and can indicate a high level of environmental pathogens

Question 19

How does the California Mastitis Test work?

Answer 19

• Estimate the SCC of milk
• Gives immediate result
• Not numerical but an indication of whether the cell count is high or low
• Only show changes above 300,000 cells/ml
• Advantage over individual cow counts: assesses the level of infection of each quarter rather than an overall udder result

Question 20

Steps to carry out the California Mastitis Test

Answer 20

1. Discard the foremilk
2. Draw a few squirts of milk from each quarter into the paddle
3. Tip the paddle so that most of the milk is discarded (ensure each quarter has even volume of milk)
4. Swirl the mixture using a circular motion and examine for the presence of a gel or slime reaction
5. Record the result by quarter
6. Rinse out the paddle before testing the next cow

Question 21

How do you score on the California Mastitis Test ?

Answer 21

A negative result is seen when the milk remains watery; a score of 3 (highest) is when the solution almost solidifies.

0 - None gelling effect
1 - Mild gelling effect
2 - Moderate gelling effect
3 - Heavy gelling effect

Question 22

What are the uses of CMT?

Answer 22

• Identification of high cell count cows and quarters
• Double checking individual cell count results
• Checking a cow you suspect may have mastitis
• Checking cell counts after mastitis
• Identifying quarters for bacteriology sampling to identify mastitis bacteria responsible for high cell counts

Question 23

Give examples of factors which can affect Bulk tank Milk Quality results.

Answer 23

• Milk from a cow with clinical mastitis entering the bulk tank can significantly increase both the Bactoscan result and the Somatic Cell Count
• Milk from a cow being treated with antibiotics will cause a Fail in the Antibiotic test
• Problems with circulation cleaning of the milking equipment (water temperature not high enough, not sufficient water or wrong concentration of detergent steriliser) usually causes a gradual increase in Bactoscan result as the cleanliness of the internal surfaces deteriorates
• If the milking cooling system fails there is likely to be a significant and sudden increase in Bactoscan result
• An increase in Somatic Cell Count usually indicates a “cow” health problems whereas an increase in only the Bactoscan result usually indicates a hygiene / equipment type problem

Question 24

Describe the functions of the main components of the milk machine

Answer 24

Vacuum pump - Continuously draws air out of the system to create and maintain a vacuum (driven by electric motor)

Vacuum regulator/controller - Automatic valve to maintain a steady vacuum despite varying levels of air leakage into the system

Sanitary trap - Separates milk and air systems and intercepts liquids to prevent flooding the vacuum pump

Receiver vessel (large stainless steel container) - collects milk from the pipeline and feeds it to the milk pump

Interceptor vessel - This intercepts stray liquid (water/milk) to protect the vacuum pump from flooding; sits on top of the receiving vessel

Milk pump - Pumps milk from the receiver vessel to bulk tank

Vacuum Gauge - indicates the level of working vacuum in the system (must be sited in the parlour and be easily visible to the milker)

Cluster - clawpiece, shells, liners, pulse tubes and milk tubes

Milk meter - measures volume of milk passing through it

Keypad - For cow identification and display of milk yields and hazard warnings

Automatic Cluster Remover (ACR) - removes milking cluster from udder when milk flow sensor detects cessation of milk flow (drops below 0.2kg/min)

Pulsators - Operates the opening and closing pulse of the liners

Jetters - Connections to the wash circuit

Milk filter - Removes any extraneous matter from the milk as it leaves the pump

Plate cooler - heat exchange unit to pre-cool the milk

Bulk tank - refrigerated tank for cooling and storing the milk

Tank washer - automatic programmed wash sequence for sterilising bulk tank

Question 25

How does Langhill identify cows whose milk is to be withheld?
And how is milk being withheld?

Answer 25

• Cows are identified by red leg tapes / red warning light on the key pad
• Cluster will not be able to be applied until we acknowledge that the milk from this cow is to be withheld
• Attach dump bucket to the cluster and this diverts the milk into a holding bucket rather than the bulk tank

Question 26

What is the pulsation rate?

Answer 26

Number of times per minute that the pulsator alternates between the milking and massage phase

E.g. A pulsator rate of 50 the teat cup liners would pulse 50 times/min

Question 27

What is a pulsation ratio?

Answer 27

Ratio of the proportion of the time that the teat cup liner is in the open position and:

• vacuum applied to the teat end (allowing milk to flow out of the teat)
• collapsed (to allow blood to flow round the teat to maintain teat health)

Pulsation ratio affects milk flow and milking time;
a careful balance is required to milk as quickly as possible but maintaining good teat health and condition

E.g. A pulsation ratio of 60:40 the liner would be open and milk drawn out of the teat under vacuum 60% of the pulse and closed to allow blood flow round the teat (no milk flow) for 40% of the pulse

Question 28

When attaching the clusters to cow teats, why should the clusters be held horizontally?

Answer 28

• to prevent air leakage into the cluster

- make each teat cup easier to attach, and will minimise vacuum fluctuations in the system

Question 29

What should be done to guide the teat into the teatcup?

Answer 29

Teatcups should be held at the very top on the liner and the index finger used to feel for and guide the teat into the teatcup. Failure to do so can result in teat being folded over in the teatcup which will then not milk out.

Normally front teat cups are applied first followed by the back ones;
Once’s fitted the cluster must hang freely under the udder so that it milks out properly

Question 30

What does overmilking mean?

Answer 30

The clusters are to be regularly left on too long on the teats
—> leads to teat end damage, cows more susceptible to mastitis

Question 31

What is used to prevent bacteria invasion of the teat canal after milking?

Answer 31

Teat canal remains open for around 30 mins after milking;
iodine based solution is used as a teat sprayer;
Spray also contains an emoillent which helps to keep the skin of the teats in a good condition

Question 32

The final stage of clean milk production on the farm is milk cooling. At langhill how many stages is the milk cooled?

Answer 32

2 stages:

1. Pre-cooling
   Uses a Plate Cooler which is a heat exchange system.
   Heat from the warm milk is transferred to cold water as they pass each other in a series of plates
2. Refrigeration
   Milk enters the refrigerated bulk tank which then takes the milk down to 4C

Question 33

How is milk quality divided?

Answer 33

• Hygienic quality: Bactoscan and Somatic Cell Count

- Compositional quality: Butterfat%, protein%

Question 34

To be in the premium band for Bactoscan, an average monthly Bactoscan level of below 30,000/ml is required. What are the possible sources that bacteria could have originated?

Answer 34

• inside the udder
• dirty teats
• the milking equipment
• the bulk tank
• poor milking hygiene

Question 35

What is the difference between sub-clinical mastitis and clinical mastitis?

Answer 35

Sub-clinical mastitis is where the milk may look normal to the naked eye,
but these cows are likely to have reduced milk yields and may be excreting large numbers of bacteria and therefore be an infection risk to healthy udders

Question 36

What is the normal range for butterfat% bulk milk from a Holstein Friesian herd?

And what are the factors affecting butterfat%?

Answer 36

3.5-4.5%, with an average 4%

• Diet: butterfat production is related to level of fibre in the diet
• Stage of lactation
• Genetics

Question 37

Normal range of Protein% ;

Factors which can affect protein%

Answer 37

• Diet (milk protein levels are related to diet energy levels)
• Stage of lactation
• Genetics

Question 38

What is extraneous water?

Answer 38

Water which has been added to the milk after leaving the cow

Question 39

How is milk sample checked to see if extraneous water is added?

Answer 39

Freezing Point Depression (FPD test)

- Checks at what temperature the milk sample freezes at and can detect quite low volumes of added water

Question 40

How can water be accidentally added on?

Answer 40

• Residual cleaning solution in the pipeline/equipment after circulation cleaning
• Residual cleaning solution in the bulk tank

Question 41

Why is the ideal time to hose down the standing is between batches of cows?

Answer 41

• Hosing faeces away while the cows are in the parlour seems to encourage others to make more mess, risks spraying dirty water over udders and clusters
• Small scraper is an useful alternative when faeces have to be cleared when cows are in the parlour

Question 42

How many times should the collecting yards be scraped and hosed per day?

Answer 42

At lease once per day

Question 43

What is the method for circulation cleaning where a single pass system involving boiling water with an added acid is called?

Answer 43

Acid Boiling Wash

Question 44

How is the milking parlour set to cleaning mode?

Answer 44

Attaching the cleaned clusters to the jetters to allow the washing system to sterilise the internal surfaces

Question 45

How often should the teatcup liners be replaced?

Answer 45

After 2500 milkings/ every 6 months (whichever is the shorter)

Question 46

How often should a milking plant be tested and serviced by a qualified engineer?
What test is carried out during milking time to check vacuum levels?

Answer 46

Every 6 months;

Dynamic Test