Abstract

The effect of experimentally induced clinical mastitis in the early dry period (EDPCM) upon the milk production in the subsequent lactation was examined. Animals with low somatic cell counts at herd test (n=165) were experimentally exposed to Streptococcus uberis in their early dry period in an efficacy study of two external teat sealants. Animals that developed EDPCM after challenge (n=127) were treated with an antibiotic after observation of clinical mastitis. Total lactation yields of milk, fat, protein and milk solids were analysed with respect to treatment group (fixed effect) and the covariables: calving week (linear), parity (linear and quadratic) and proportion of Holstein-Friesian genes (linear). For animals that suffered EDPCM and those that did not, there was no difference in production (milk yield; 5126 vs. 5010 litres, fat yield; 267 vs. 264 kg, protein yield; 182 vs. 179 kg). It was concluded that promptly treated EDPCM due to S uberis, did not affect production in the subsequent lactation.

KR, Petrovski, NB Williamson, C Fernandez, A Grinberg, N Lopez-Villalobos, and TJ Parkinson

Proceedings of the New Zealand Society of Animal Production, Volume 67, Wanaka, 303-306, 2007