WITHEE — The topic of somatic cell counts in milk is not a new one, but it is an important one, Marathon County UW-Extension Dairy Agent Heather Schlesser said at a Dec. 13 dairy management meeting in Clark County.
“Somatic cells are not affected by breed, milk yield, stage of lactation, nutritional management or other cow diseases, meaning they are independent of anything else going on in the cow,” Schlesser said. “They are affected by management practices that expose teats to bacteria that cause mastitis.”
Schlesser said farmers will often notice abnormalities in milk with high SCC, including discoloration and chunks, but those physical characteristics are the immune response of the bacterial infection, not the actual infection.
“If it looks like snot in your handkerchief, that is not 200,000 cells,” she said.
Schlesser said farmers should care about high somatic cell counts because it costs them money in losses in milk production and if the infection becomes bad enough, the cow may need to be treated with antibiotics, causing its milk to not be able to be shipped.
Mastitis problems often increase in the summer because of the warmer temperatures providing good growing conditions for bacteria.
“Bacteria love to grow in the summer,” Schlesser said. Minimizing their contact with the bacteria is crucial to preventing infection. Contagious mastitis is spread through direct contact so it is important to limit that contact as much as possible. This includes cleaning teat cups, using clean towels from cow to cow and washing hands often during milking. It can also be spread through flies or suckling so farmers should look at ways to reduce those too.
Contagious mastitis can also be spread from infected milk in the milking unit, so cows that are confirmed infected should be milked last in the milking rotation.
When looking at SCC, Schlesser said it is important for farmers to look at individual cows and not just the bulk tank count.
“If you are not measuring somatic cell count on individual cows, you cannot manage subclinical mastitis,” Schlesser said. Subclinical mastitis shows no abnormalities in milk and will go undetected if not tested for.
Schlesser said the California Mastitis Test is a simple and fast test that can show whether a cow is infected with subclinical mastitis. Once the cow is diagnosed, it can be treated.
Another key to managing SCC is making sure cows are comfortable and that their stalls are meeting their needs to prevent them from lying in alleys or gutters. If you find that many of the cows are lying improperly, analyze the stall design, bedding and other environmental issues to figure out the reason.
Overall, solving the source of SCC problems can be difficult to do alone. Schlesser suggests having a team of people working on the issue.
“Bring in consultants and have them work as a team to see what is happening on your farm,” she said.