On the basis of glucose fermentation and lysostaphin sensitivity, 71 gram-positive, catalase-positive cocci, isolated from mastitic ovine milk in Spain, were classified as members of the genus Staphylococcus. Identification at the species level was accomplished by complete characterization of the staphylococcal strains. Fifty-nine of the isolates were classified as S. aureus, 1 as S. simulans, 5 as S. epidermidis, a as S. haemolyticus and 5 could not be classified as any accepted or newly proposed species. The number of strains lysed by phages of S. aureus of human and bovine origin was 8 and 40, respectively. The phage pattern most frequently found was 78 (34 strains). Fifty of the S. aureus strains belonged to biotype C. Forty-nine of the S. aureus strains and 2 of the unclassified ones produced enterotoxin: 46 produced enterotoxin C, 2 produced enterotoxin A, 1 produced enterotoxin D and 2 produced both enterotoxins A and C. Forty-one of the 46 enterotoxin C producers belonged to biotype C, and 31 of these were lysed by phage 78.

A total of 195 Gram positive, catalase positive cocci, isolated from ovine mastitis, abscesses in slaughtered animals and parasitic pulmonary lesions in lambs were tested for glucose fermentation, anaerobic growth in thioglycollate medium, coagulase production and susceptibility to the lytic action of lysostaphin. On the basis of lysostaphin sensitivity, 192 strains were classified as staphylococci. The number of cultures able to produce acid anaerobically from glucose, or giving a positive result in the test of Evans and Kloos was lower. A good correlation among these three tests was not observed. Ninety-seven of the strains tested gave a positive coagulase reaction. Sensitivity to lysostaphin could not be used as a criterion for the differentiation of coagulase positive and coagulase negative strains. The turbidimetric method employed for the assessment of lysostaphin sensitivity is discussed.