Isolation and Identification of Staphylococcus aureus from lactating goat milk

Abstract

Staphylococcus aureus is an opportunistic pathogen that causes both superficial, suppurative, and potentially life-threatening infections. They are gram positive, non-motile, facultative anerobic bacteria that are small, round, grapes like cluster forming. The present cross-sectional study was conducted to isolation and identification of S. aureus bacteria from lactating goat milk. Randomly 5 ml of milk sample was collected from ten healthy lactating goat. This samples were streak in 5% Bovine Blood agar and observe bacterial growth and the colony morphology. After 24 hours in blood agar S. aureus found as smooth, small, circular raised with gray yellowish color colony. Further this bacterial colony was streak in Mannitol salt agar that is a selective media for S. aureus. Finally small to large yellowish colonies found In MSA agar plates. The pure cultures were further subjected to catalase tests for biochemical confirmation. Evisceration of gas bubbles indicates positive test result. From this study,3 S. aureus were isolated from 10 healthy lactating goat milk samples. Overall, 30% prevalence of S. aureus were found in goat milk. S. aureus is one of the major pathogens cause clinical and subclinical mastitis in goat.