At this time of year, when the herd reaches peak milk production, the bulk milk somatic cell count (SCC) is at its lowest. But from here on, the bulk milk SCC level will only rise.
Systems to prevent new infections, and find and treat mastitis, have a large impact on degree and speed of this rise in SCC.
Reduce the risk of grading
Did you know your risk of SCC grading in autumn is linked to your bulk milk SCC at peak milk production?
For herds at 100,000 cells/ml now, the risk of grading for SCC, once or more by the end of lactation, is about 39 percent. This rises to 56 percent for herds at 150,000 cells/ml and 71 percent for herds at 200,000 cells/ml.
To keep your season grade-free, take steps now to reduce mastitis and thus improve bulk milk SCC.
Bulk milk SCC doubles
Between the third and last month of supply, the bulk milk SCC generally doubles. The figure below shows this for herds that averaged 150,000 cells/ml for the whole season.
Two things are driving this rise – firstly, the spread of new infections between cows at milking time and, secondly, a steady increase in SCC as milk volume declines.
You can’t prevent the latter but you can prevent new infections.
Reduce mastitis spread
Don’t be fooled into treating high SCC cows or culling too early. These are expensive and ineffective ways to reduce the bulk milk SCC.
The best way is to look after the teats. Use a registered teat spray, make it up to the right dilution for your herd’s mastitis risk and check that every teat is covered after every milking.
Maintain the milking machine and fix problems promptly to help prevent unnecessary teat damage.
Continuing to do the same thing and expecting a different outcome is a quick route to insanity! If you want to better prevent mastitis, seek help.
The SmartSAMM team are developing a New Zealand-wide initiative with vets. Called the Healthy Udder Service, this will help develop long-term and effective solutions for your herd.
Particular vets are also accredited by the National Mastitis Advisory Committee (NMAC) to perform detailed mastitis investigations, which can be eligible for demerit relief. Such investigations are often the only way to get to the root cause of a problem and achieve long-term solutions.
Check your SCC now and predict your risk for autumn. Time and effort invested now will reap benefits after Christmas.
This article was originally published in Inside Dairy October 2013