Weather impacts somatic cell counts in milk

Farm Forum

BROOKINGS – Wet weather conditions experienced in eastern South Dakota increase the risk of mastitis and the resultant increase in somatic cells counts on dairies, says Alvaro Garcia, SDSU Extension Dairy Specialist.

“Some herds have already experienced moderate spikes in somatic cell counts in their milk during the month of May, an indication that an inflammation process is occurring in the udder,” Garcia said.

This comes at a time when counts state-wide have trended downward.

“Dairy somatic cell counts have seen constant improvements in the state,” Garcia said.

In the last five years dairy herds on DHIA in South Dakota have improved somatic cell counts by nearly 21 percent from 282,000 to 255,000. He adds that during the last year alone this improvement was 13 percent from 255,000 to 222,000.

What to do if your counts increase

If producers need to address a sudden increase in somatic cells during wet weather Garcia says they should consider two main areas:

First, make sure an adequate milking protocol is followed.

“Place particular emphasis on stripping (at least three squirts) to eliminate the most contaminated milk first, which is the one present in the teat cistern,” he said.

Make sure that teat dip coverage is thorough and that it remains in contact with the skin for at least 20 seconds. Garcia says using clean, dry towels to wipe the teats clean is critical.

“Make sure cloth towels are washed properly with detergent and bleach and the temperature setting in the machine is on hot – not just warm,” Garcia said.

Do not overload the washing machine as this will not allow for a good washing cycle. Make sure the drier is not overload also to allow towels to dry completely. Ask employees to maintain the towel bins closed while not being in use to prevent manure to splash on the clean towels. Cutting a relatively small round hole on the lid of the tote through which the towels can be retrieved will reduce the chances of them getting soiled while in the parlor.

Second, he says producers should focus on cow comfort and cleanliness.

“Make sure bedding is replaced as often as possible, and that it is clean and dry,” he said.

He says deep bedding replaced less often is worse than more-shallow bedding that producers replace daily.

“Those producers that use recycled manure solids or bedded packs as bedding must take extra precautions during wet weather by removing solid bedding often,” Garcia said. “These two types of bedding are high in organic matter and an increase in moisture will promote bacteria proliferation.”

In addition, Garcia says manure-soiled water from alleys is more likely to splash on udders in barns that are not cleaned regularly. It happens more often when cows are moved rapidly from the parlor.

In general, Garcia says milking protocols have been more consistent and milk quality has improved when the same person takes care of stripping, pre-dipping, drying the teats and attaching the unit.

Any producer who feels the need to revisit the milking procedure of his employees can contact SDSU Extension Dairy Specialists for help.

“It is easier to correct any milking procedural drifts early than to wait after somatic cells increase too much,” Garcia said.

Any producer interested in establishing a clinic for their dairy, or needing to work with a SDSU Extension Specialist, may contact an SDSU Extension Regional Center or call the SDSU dairy science department at 605 688-4166.

Visit for more information and a complete listing of SDSU Extension Regional Centers.