Taxonomy of some Staphylococci and Micrococci Isolated from Bovine Teat Canals and Foremilks

SUMMARY The taxonomy of 2404 cultures of Gram positive, catalase positive, nonmotile cocci was determined using Baird‐Parker's (1963) classification. The bacteria were isolated from bovine teat canals and milk samples during 2 lactations of an experimental herd of cattle and their taxonomic positions were assessed on the basis of 8 reactions. Most were clearly assigned to typical subgroups, although some arabinose positive staphylococci and VP positive and phosphatase positive micrococci were atypical. Cultures representative of these and typical subgroups were examined in more detail using 25 reactions. Most cultures were again classified as being typical but it was shown that the atypical cultures were genuinely different from bacteria examined by Baird‐Parker. A marked difference was found in the results of the phosphatase reaction on Baird‐Parker's phosphatase medium and on that prepared with a different base used in this work. The atypical micrococci gave a negative result when tested on Baird‐Parker's medium but their carbohydrate reactions still differentiated them from other subgroups. Carbohydrate oxidation tests varied in intensity depending on whether the medium was prepared as slopes or plates. The slopes gave a more intense reaction which persisted once a positive reaction occurred. The methods used provide additional means for epidemiological studies of Micrococcaceae in dairy herds.