BOVINE CLINICAL MASTITIS DUE O COAGULASE-NEGATIVE STAPHYLOCOCCI AND THEIR SUSCEPTIBILITY TO ANTIMICROBIALS

A total of 168 coagulase-negative staphylococci (CNS) strains were iso lated from milk samples taken from cows with clinical mastitis. The sa mples were collected between January 1990 and August 1992 from cows in the veterinary surveillance area of the Ambulatory Clinic, College of Veterinary Medicine, Hautjarvi, Finland. In 100 cases the effect of a ntibiotic treatment was evaluated 3-4 weeks after initial sampling. Cl inical symptoms of the animals were recorded, and the inflammatory sta tus of their udders was evaluated using the CMT test and assessing mil k NAGase activity. CNS mastitis was most common in young cows during e arly lactation. Staphylococcus hyicus, S. simulans and S. epidermidis were the most frequently isolated CNS. Clinical symptoms were most sev ere with S. hyicus. Cure rates for CNS induced mastitis were high.