Milk Quality: Winter is Coming

Now is the time to begin to think about teat end and teat condition issues typically observed in colder weather. Many herds have a history of winter teat lesions and just assume they are normal because it happens every year.

Teat end condition is directly related to milking duration. Key factors to consider when investigating a teat end condition issue on any dairy are udder preparation, take-off settings, peak flow average, vacuum level and pulsation performance. 

Avoid Dry Milking

Udder preparation is important because the two most common times for dry milking are shortly after the units are attached and toward the end of milking. The chart below illustrates when low flow is likely to occur.

The main control points for dry milking are the consistency of udder preparation and the take-off settings. An increase in duration means teats are subjected to more liner openings and closings. When teats are full of milk the effects of liner movement are minimal. However, when teats have little or no milk flow, liner movement is not cushioned by milk in the teat canal and the teat cistern.

The movement of the liner will stretch the teat in length and diameter, resulting in micro fissures in the outer layers of the skin. During colder periods, skin is drier because the air is drier. This makes teat skin more likely to crack due to the stretching initiated by liner movement. Damaged skin produces more skin and keratin, which results in hyperkeratosis lesions.

With adequate and consistent udder preparation the low flow period at the front end of milking will be minimized. Optimal oxytocin levels will be achieved and cows will reach peak milk flow sooner and milk out quicker.

Keep Teats Dry

Drying teats is critical. Make one circular motion on each teat, then flip the towel and aggressively pinch each teat end. Always start on the far teats and move to the closer teats to minimize recontamination.

Take off settings can be adjusted to remove units as soon as milk flow is reduced to an appropriate level. Strip milk as soon as the units come off. Use a cup and record the amount of milk and the resistance of the cows to being stripped. The goal is 100 mL to 250 mL from all four teats when stripped immediately after units detach. If cows have little milk and are resistant to stripping, adjust take-off settings to reduce milking duration.

The biggest cause of poor teat condition is low average peak milk flow claw vacuum levels. When performing a system analysis, closely examine the milk path. Minimize hose lengths and uphill movement of milk to improve the average peak milk flow claw vacuum. This principal applies to both parlor and highline milking systems and can be done in any herd even if the udder preparation and takeoff settings have not been optimized.

Pulsator performance is also important. Any deficiencies can result in an inadequate teat massage leading to more teat end congestion, cracking and stress. These factors will increase the appearance of teat lesions. 

Milking Tune Up

Having a tune up of the milking system and milking techniques will reduce the incidence of teat end lesions. When evaluating teat end condition, look at a representative herd sample and not just cows in the treatment pen. Most cows in treatment pens will have some of the worst teat condition because teats with poor condition are more difficult to clean during routine udder preparation and therefore are more likely to have mastitis.

David A. Reid, DVM owns and operates Rocky Ridge Dairy Consulting, LLC based in Hazel Green Wisconsin. Reid has 44 years of experience as a practicing dairy veterinarian and dairy consultant.

Note: This story appears in the December 2017 magazine issue of Dairy Herd Management.