Epidemiology and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus in Cattle of Pothohar Region, Pakistan.

Sub-clinical mastitis has remained the leading cause for decline in production of dairy animals as a silent epidemic all the times in Pakistan. A questionnaire-based cross-sectional study was conducted to assess the prevalence and potential risk factors for sub-clinical mastitis in the Pothohar region of Pakistan in 2018. Total of 104 cattle milk samples were collected from commercial and subsistent dairy farms. CMT positive samples were cultured and biochemical tests were conducted before confirmed on PCR for mecA gene Methicillin Resistant Staphylococcus aureus (MRSA) bacteria. In-vitro antibiotic susceptibility was also assessed. An overall prevalence of 71.1% was found; where cross-bred was found more susceptible (80.7%) as compared to other breeds. MecA gene-MRSA prevalence based on PCR was 54%. On regression analysis the potential risk factors identified here included; daily milk yield, parity, udder shape, teat morphology, shed type, quarantine of new animals and deworming of animals (OR>1; P-value<0.05). In MRSA confirmed isolates, Penicillin group was found highly resistant (92.5%) amongst all the groups. While amongst individual antibiotics Amoxicillin was found highly (100%) resistant followed by Cefixime and Spectinomycin. Whereas based on sensitivity Quinolone (Moxifloxacin 95%) group was the most sensitive (91.7%) followed by Sulphonamides (Sulphaphenazole 87.5%) and Amino-glycoside (Gentamycin 90%). An emerging pattern of mecA gene MRSA was recorded here with alarming sub-clinical mastitis prevalence in the study area. Immediate preventive measures need to be taken to address the problem. The findings of the current study will assess in control and prevention of subclinical mastitis in Pakistan. [ABSTRACT FROM AUTHOR]