Staphylococcus species, mainly S. aureus, S. intermedius, and S. hyicus species, are the primary causes of intra-mammary infections in cows and causes human food poisoning infections
hence, this study aimed to assess the prevalence, antibiogram, virulence, and methicillin resistance gene profiles of pathogenic Staphylococcus species from bovine milk samples. A cross-sectional study design was employed to collect milk samples from February to August 2022 from 290 lactating cows in 38 small and medium-scale dairy farms. Isolation of pathogenic Staphylococcus species was performed by plate culturing and biochemical tests and the antimicrobial susceptibility profiles were determined by Kirby-Bauer disc diffusion method. Virulence and methicillin-resistant genes were detected using conventional PCR. Logistic regression and Chi-square test were used for data analysis. The overall Staphylococcus species prevalence was 16.6% (95% CI= 12.5-21.3). Of these, 52.1%, 33.3%, and 14.6% were S. aureus, S. intermedius, and S. hyicus species, respectively. Farm management, herd size, parity, milk yield and breed risk factors had a significant association with the occurrence of Staphylococcus species. All the isolates showed 100% resistance to amoxicillin and ampicillin discs, while 41.7% (95% CI= 27.6- 56.8) of the isolates showed multidrug resistance. The study revealed that 68.8%,33/48 (95% CI= 53.7-81.3) of the pathogenic Staphylococcus isolates carried one or more of the virulence and/ or methicillin resistance genes. The mecA, hlb, hla, icaD, pvl, tsst-1, and sec genes were detected in 58.3%, 54.2%, 50%, 41.7%, 29.2%, 10.4%, and 4.2%, respectively, from 48 Staphylococcus isolates. The study revealed that pathogenic Staphylococcus isolates carried various virulence and became multidrug resistant
which necessitates employing Staphylococcus caused mastitis control and prevention measures.