Milking Parlour and Mastitis Flashcards
How often do rubber units on clusters have to be replaced?
Every 2500 milking’s or every 6 months - whichever is closest
Describe the pathway of milk from the udder to the bulk tank
Udder -> teat -> short milk tube -> claw -> long milk tube -> bulk tank
Which feature on the cluster is required to allow milk to enter the claw?
Air bleed hole
How is milk removed from the udder by the milk machine?
Milk removed by creating negative pressure outside the teat – applying a vacuum (42-48 kpa) controlled by regulator
Does the vacuum on the milk machine need to be continuous, or not? Explain
Continuous vacuum would stop circulation in teat. Applied intermittently via pulsator liner opens and closes allowing teat to rest and circulation restored, 60/min
Which part of the milking machine connects the claw piece to the bulk tank?
Long milk tube
Where do environmental and contagious mastitis pathogens live?
- Contagious pathogens spread from cow to cow in the milk
- Environmental pathogens on teats and teat ends
What happens to the milking machine when the vacuum is off/on?
Vacuum off
- Liner closed
- Milk flow stops and test rests
Vacuum on
- Liner opens and milk flows out
How is the milking parlour involved in mastitis?
Milking Parlour Hygiene - prevent introduction and spread of infection
Milking machine:
- Damage to teats and teat ends
- Vector for spread of infection
Contamination of which part of the milking machine leads to transfer of pathogens onto teat skin?
Liners
How can inadequate milking machines lead to milk being flushed upwards into the teat canal, carrying pathogens with it?
Inadequate vacuums
Fluctuating vacuum
Blocked Air bleed
How can vacuums on milking machines lead to problems
- Too high
- Settings
- Regulator (usually in dairy) not working (if it is you should hear a hissing sound) - Fluctuating/ Inadequate vacuum:
- Inadequate vacuum pump
- Holes in tubing
- Liner slip/ clusters falling off
- Inadequate vacuum reserve
What are the consequences of a blocked air bleed?
Flooding of the claw piece
So milk not drained away from claw piece properly
- Teat end impacts
- Fluctuating vacuums
Why does faulty pulsation on milking machines cause problems?
Poor circulation
Set too fast (60 per minute) poor circulation
Set Inadequate rest phase (poor circulation)
Holes in tubing
List some simples tests that need to be carried out on milking machines
- Examine clusters: blocked air bleeds, cleanliness of liners, wear on liners, holes in tubing
- Vacuum gage in parlour note level and watch whilst milking and observe for fluctuations
- Liners slipping see, hear “shh” sound inadequate vacuum
How should you observe cows in the milking parlour?
Paddling or kicking – if uncomfortable:
- Over milking (at end)
- Faulty vacuum or pulsators
- Excess vacuum
- Hard liners
Teat score
Describe the key features of milking parlour hygiene
- Major site of spread of mastitis organisms
- Key area for good hygiene for mastitis control
- Takes time and attention to detail
- Staff may want to get through milking quickly
- Problem as herds get bigger and manpower reduced on farms: but may be more focussed
- Easy to cut corners
- Look for stones/bricks in parlour used to weigh clusters down
- Observe routine and see if ALL staff follow it!
Which features of the milking parlour/routine need to be assessed in terms of hygiene
- Gloves
- Premilking Teat Preparation: Fore-milking, teat disinfection
- Post Milking Teat Dipping
- Loafing time
- Parlour Management of clinically or sub-clinically infected cows
- Milking Order, Cluster Disinfection
- Parlour wash up routine
Describe fore milking
Legal requirement
Early detection of mastitis
Stimulation of milk let down reflex
The first milk drawn from a cow’s udder prior to milking
Describe cleaning and disinfection as part of the pre-milking teat preparation and why is it used
- Depends on how dirty teats are therefore how dirty environment is
- Decrease environmental bacterial contamination
- Good for public health
- Reduce mastitis esp.environmental pathogens like Streptococcus uberis and Escherichia coli
- Aids in milk let down therefore rapid milking
Describe the 6 methods of pre-milking teat preparation
- None
- Wipe with common udder cloth (not enough)
- Disinfectant wipe - one per cow
- Wash (+disinfectant) +/- Dry
IF WASH MUST ALWAYS DRY - Spray or Dip cup with disinfectant
- Foaming products
List some common disinfectants used to prep the teats
Chlorhexidine
Iodophors
Chlorine dioxide
What else needs to be considered when using disinfectants to make sure its done properly?
- Correct concentration being used
- Correct contact time 30 sec – 2 mins
- Thorough teat coverage often not with sprays (esp automatic)
Timing between cow being prepped and cluster application should be …?
Between 30 and 60 seconds
How can you make sure the timings between prep and cluster application are met?
Group cows into small groups
Describe the milk ejection reflex
- Teat stimulation causes afferent neural inputs terminating in paraventricular nucleus of hypothalamus
- Oxytocin released from posterior pituitary
- Oxytocin causes contraction of myoepithelial cells in the mammary gland
- Stimulation to secretion delay determines milking routine
What happens if the time between prep and cluster application isn’t right?
Slow milk let down initially - can lead to teat end damage
Describe the steps in a typical milking routine from start to end
- Clean (pre-dip or wipe)
- Identify animal?
- Foremilk – inspect for clots – legal requirement
- Leave 30-45 seconds for oxytocin release and action
- (Wipe if pre-dipped)
- Cluster on
- Milk flow reduced
- Cluster removed
- Post milking teat dip applied
- Loafing time to allow teat sphincter to close?
How can you prevent exchange of milk between quaters?
Claw piece with valves
Liner with air vent
How can bacteriology of milk be assessed?
Milk filter analysis
Describe post milking teat dipping and explain why it is done
- Remove bacteria transferred to teats during milking
- Key prevention for infection with the Contagious pathogens;-Staphylococcus aureus, Streptococcus dysgalactiae and Streptococcus agalactiae
- Can see where the teat has been dipped due to red dye
Describe loafing time and why it is used
Allow closure teat sphincter post milking
Prevent environmental infections
30 minutes
Clean area
When is loafing time contra-indicated?
It can exacerbate lameness issues
Why would you want to implement a milking order?
Preventing spread of infection
Milk least likely to be infected and most susceptible first
List a typical milking order for the 6 types of cow you may have on farm
- Heifers
- Fresh calvers
- High yielders
- Low yielders
- High cell count cows
- Mastitic cows
Describe the features of a parlour wash routine
Clean milk out and remove bacteria deposited
Cold rinse (once daily)
Hot wash (once daily)
Rinse with hypochlorite
Acid and alkali washes
What are some possible problems of the parlour wash routine
Not hot enough (>60C so tank needs to be 85-90C)
Not enough hot water 10-12 litres per unit
Hot washing needs to be done in the parlour after every milking if which agent is present on farm?
Staphylococcus aureus
