Persistent Coliform Mastitis

Abstract

The debate over treating clinical mastitis with an antibiotic has hinged around the isolation of environmental pathogens. Although intramammary antibiotics may be successful in eliminating gra~-positive organisms, beta-lactam antibiotics have little efficacy on gram-negative organisms. Research also reports¹ that many of the gram-negative coliforms are self-eliminating, and are generally cleared by the time clinical mastitis is detected when antibiotics are administered. However, others have reported² that coliforms can persist without treatment and can contribute to increased somatic cell count in a herd. This study looked at the persistence of gram-negative coliforms in quarters that have been identified by culture at the signs of clinical mastitis.