PREVALENCE AND ETIOLOGY OF NONCLINICAL INTRAMAMMARY INFECTION IN MURCIANO-GRANADINA GOATS

Ten herds of Murciano-Granadina goats were examined to determine prevalence and aetiology of subclinical mastitis in Murcia (Spain). In the 369 milk samples analysed from 188 animals, intramammary infection was present in 18% of the glands and 30% of the goats. Prevalence of infection in the different herds ranged from 7% to 34% of the glands and 17% to 44% of the goats. Sixty-nine bacterial isolates were found, comprising staphylococci (71%), corynebacteria (12%), mycoplasmas (9%), enterobacteria (3%), pasteurellas (3%), streptococci (1%) and yeast (1%). Among the 49 staphylococcus isolates, Staphylococcus caprae (22%), Staphylococcus epidermidis (20%) and Staphylococcus chromogenes (12%) were the most frequent of the 12 species identified. Staphylococcus aureus (6%) had a low prevalence, and only one isolate was coagulase positive. S. caprae showed the highest prevalence among the herds, and mycoplasmas and S. epidermidis were most responsible for bilateral infections (60% of those detected).