Staphylococcus spp. as mastitis-related pathogens in goat milk.

A total of 359 Micrococcaceae strains isolated from goat milk samples were differentiated with the commercially available ATB 32 Staph differentiation system. Of these strains, 303 (84.4%) were identified. Six strains were sensitive in the bacitracin resistance test, and accordingly classified as Micrococcus spp. Staphylococcal species isolated of goat milk were S. epidermidis, S. aureus, S. caprae, S. lentus, S. simulans, S. capitis, S. lugdunensis, S. xylosus, S. chromogenes, S. hominis, S. arlettae, S. warneri, S. sciuri, and S. saprophyticus. Highest somatic cell count (SCC) in milk and the highest prevalence of clinical udder alterations were associated with coagulase-positive S. aureus. Increases in milk SCC as well as pathological udder findings were observed in infections with coagulase-negative staphylococci such as novobiocin-sensitive S. epidermidis, S. simulans, S. lugdunensis, S. chromogenes, and S. warneri.