The first of the milk lorries rolled on to farms collecting milk last week, so the first milk quality test results are being texted back to farmers this week. The first few loads of milk often present surprises, with high SCC and TBC results.

High somatic cell count indicates the presence of infection in the milk. The body sends out white blood cells to fight the infection and it is these white blood cells that cause high SCC. Therefore, curing the infection will decrease the SCC.

But finding the offending cow or cows is the challenge. The first thing to do is to check the milk filter for signs of clots. Farmers should be doing this every day anyway, but particular attention should be placed to it when sorting an SCC problem.

If there are clots in the filter, it means there is a cow or two with clinical mastitis. Pre-stripping before milking will usually pick up the offending cow(s). Cows should probably be pre-stripped at least once a day when indoors and the risk of mastitis is high.

CMT test

Where no clots are present and the SCC is still high, using a CMT test is the next step. The CMT test uses a reagent that forms a gel when mixed with high SCC milk. CMT test kits are readily available in most farm stores or can be homemade by mixing washing-up liquid in water.

Squirt some CMT solution into a sample of milk from each quarter, swirl the sample for a few seconds and observe the reaction. Where the milk turns into a gel, this indicates high SCC and that cow should be treated in that quarter.

While it is a slow process to CMT-test a line of cows, the results are instant, so is a worthwhile practice. It would be a good idea to CMT-test the milking cows when a relatively small proportion is calved and then CMT all cows on their last milking before their milk is ready for the bulk tank.

Consult with your vet about the best products to use to treat the infection. Some vets will prescribe an anti-inflammatory along with an antibiotic. Antibiotics can be given into the muscle or into the udder.

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