Identification of Staphylococcus species of bovine origin with the API Staph-Ident system

Abstract

The API Staph-Ident system was evaluated as a means for identifying the species of bovine strains of staphylococci routinely isolated from quarter-milk samples. The species identity of 314 of 581 (54%) isolates of staphylococci was correctly determined by this method. The API Staph-Ident system was more accurate in correctly identifying Staphylococcus alureus (93.9%) than in correctly MATERIALS AND METHODS Bacterial isolates. During a 20-month period, 581 gram-positive catalase-positive cocci of bovine origin were obtained by our laboratory from several sources. A total of 25 isolates were obtained by swabbing the distal end of the streak canal of 14 cows in the University of Kentucky dairy herd during their dry period. The remaining isolates were obtained from the following sources: 96 were activated from freeze-dried cultures of isolates obtained from quarter foremilk samples from the University of Kentucky dairy herd in 1969 (25, 26), 383 were from quarter foremilk samples obtained from the University of Kentucky dairy herd during the 20-month period of this study, 32 were from two private dairy herds in Kentucky with a high incidence of mastitis (18, herd A; 14, herd B), 37 were from J. W. Pankey, North Louisiana Hill Farm Experiment Station, Homer, La., and 9 were from K.

Slime production by bovine milk Staphylococcus aureus and identification of coagulase-negative staphylococcal isolates

“…Thus, we found a significantly different distribution. S. epidermidis made up the highest proportion of the isolates in the study by Langlois et al (19), with a variety of other species being found. In addition to S. aureus, S. simulans was often present in pure or heavy culture in our milk samples, which may indicate that this species has the ability to cause mastitis.…”

“…The API Staph-Ident system is designed for the rapid identification of staphylococcal species. Several studies have documented its use in identifying human staphylococcal species (1,5,18), but only one study has investigated its applicability to bovine isolates (19). Assuming the identifications given by the Kloos and Schleifer scheme are correct, the species most often correctly identified by the API system was S. aureus (82.3%).…”

“…The API Staph-Ident system, which was developed for the identification of human staphylococcal strains, correctly identified only 45.2% of these bovine isolates. This may have been due to biochemical differences between bovine and human staphylococci (19). Also, the results were difficult to interpret at times, with borderline reactions, especially in the carbohydrate tests, that were difficult to score as positive or negative.…”

“…artificial medium for 1.5 to 3 years were not encapsulated, although 28.8% of them grew as diffuse colonies in serumsoft agar. Langlois et al (19) reported that the API Staph-Ident system identified correctly only 41.8% of non-S. aureus bovine staphylococci from quarter milk isolates.…”

Evaluation of Two Commercial Systems and a New Identification Scheme Based on Solid Substrates for Identifying Coagulase‐Negative Staphylococci from Bovine Mastitis

“…Results obtained with these rapid identification kits for bovine strains have not been very reliable. Early reports have shown levels of agreement with conventional methods that were as low as 42 % (Langloise et al, 1983). Today, some U. S.…”