Case study: Selective Dry Cow Therapy reducing antimicrobial use and resistance

29 May 2026

Keeping the prevalence of antimicrobial resistance (AMR) low, and ensuring that antibiotics remain effective in the long-term, are a key part of the updated prescribing advice for dry cow therapy (DCAT) which comes into effect on 1 January 2027. The Veterinary Council of New Zealand’s new Statement on the authorisation of dry cow therapy supports a shift in practice to selective DCAT, backed by research which found it is unlikely that herds with a low bulk milk somatic cell count, low incidence rate of clinical mastitis, and low culling percentage for mastitis-related problems have many cows truly infected at the time of dry-off. Where a cow is unlikely to be infected, internal teat sealants (ITS) should be used rather than antibiotic dry cow therapy, to prevent new infections over the non-lactating period. DCAT remains the appropriate choice for individual cows where infection is indicated.

At Taranaki Veterinary Centre, reducing the use of critically important antibiotics and reducing whole herd DCAT usage has been underway for several years, and is achieving great results. The Centre, which has clinics in Stratford, Waverley, Patea, Hawera and Manaia, has a diverse client base, with dairy farms making up about 80 per cent of it.