Hemolysin production by Staphylococcus aureus species isolated from mastitic goat milk in Brazilian dairy herds

Staphylococci isolated from mastitic goat's milk in 29 Brazilian dairy herds were analyzed for the production of alpha, beta and delta-hemolysin on sheep and horse red blood cells. Of the total strains studied, 80% demonstrated hemolytic activity. Among coagulase-negative staphylococci (CNS) isolated from subclinical mastitis, 65.2% produced alpha-hemolysin, 19% beta-hemolysin and 83.3% delta-hemolysin, either alone or combined. Staphylococcus aureus isolates showed hemolytic activity for all hemolysin types studied-76.7% of them produced alpha-hemolysin, 74.4% beta-hemolysin and 83.7% delta-hemolysin, either alone or co-produced. The results suggest that goat's mammary glands are an important reservoir of hemolytic staphylococci.