The Value of re-treating the dry cow

Abstract

Since the anti-mastitic effects of mammary gland infusion carried out at drying off last for approx. 20 days, whereas dry period tends to be approx. 60 days, a study was carried out to assess the economic and prophylactic value of re-treatment of cows during the dry period. Udders of Holstein cows that had been selected alternately from a herd of 420 were infused with Cephalosporin (200 mg/quarter) 2-3 wk prior to parturition. Incidence of mastitis at and after parturition was then assessed, and costs of re-treatment were compared with costs for treatment of mastitis outbreaks. For simple mastitis, cost of prophylactic retreatment was considerably higher than cost of treating one episode of mastitis; costs for treatment of severe mastitis were, however, approx. equivalent to costs of re-treatment. Routine prophylactic re-treatment is not therefore recommended for cows prepartum unless there is a high incidence of severe clinical mastitis post partum.