DairyNZ: Focus on mastitis control makes life easier for farmers

Focusing on good mastitis control during lactation, and keeping animal health treatment records up to date, helps makes life easier at culling and dry off. Selecting cows for dry cow antibiotics is simpler when there are fewer infected cows in the herd.

By targeting antibiotics to only those cows with udder infections, and protecting other cows with non-antibiotic alternatives, we help reduce the risk of bacteria becoming resistant to antibiotics. Resistance to antibiotics will ultimately lead to poorer outcomes for animals receiving treatments, and there's a real risk that antimicrobial* resistance can affect the bacteria that cause infections in people.

Minimising the spread of infections during the milking season helps reduce the number of cows requiring antibiotics at dry off. Better control of contagious mastitis will also reduce the risk of missing cows that could develop new infections, close to drying off.

Top tips from two top farmers

Brendon O'Leary farms 400 cows near Gordonton. He puts his biggest focus on tracking the high-risk cows, those that went clinical this spring. He keeps a regular eye on their treatment records and how their somatic cell counts are tracking during the season — are they getting better, or are they joining the 'three-strikes' list? (Those that have had three separate cases of clinical mastitis and have become chronic infections.)

He finds good data recording now means better decisions when it comes to culling and drying off. During spring and summer, Brendon also adds additional emollient in the teat spray, to keep teat condition soft and supple and reduce the spread of infection.

Laurence Bartley contract milks for Alister Smith at Gordonton. Laurence has a similar view to Brendon, keeping a close eye on the sub-clinical cows found at calving (those that went positive when tested with the rapid mastitis test).

So long as they don't go clinical, they don't receive antibiotic treatment, but they are marked up with green tail paint and tested regularly for clinical signs during the lactation. As well as helping keep the herd grade-free, he also gets some of these cows checked for mastitis bacteria, which helps to make good decisions at dry off, when many of these cows are targeted with dry cow treatment.

Laurence acknowledges that he's a firm believer in the value of teat spraying, keeping the concentration of the active ingredient and emollient high when the weather is wet and reducing it when the risk is lower.

Find out more at dairynz.co.nz/dryingoff

*An antimicrobial is any substance of natural, semisynthetic or synthetic origin that kills or inhibits the growth of microorganisms but causes little or no damage to the host.

KEY POINTS
* Keep a close eye on at-risk cows.
* Keep teat spraying — every cow, every milking, every day.
* Keep treatment records up to date.
* Resistance to antibiotics will ultimately lead to poorer outcomes for animals receiving treatments