Detection and Antimicrobial Resistance Profile of Salmonella Isolated From Raw Cow Milk and Its Products in Bishoftu Town, Central Ethiopia: Implication for Public Health

Background Salmonella is a significant foodborne pathogen, with milk and milk products commonly implicated in its transmission. However, limited information is available regarding the direct link between antimicrobial use (AMU), dairy hygiene practices, and antimicrobial resistance (AMR) in Salmonella strains isolated from dairy products in Bishoftu town. Methods Cross-sectional research was done from October 2023 to April 2024 to assess dairy farmers' antimicrobial usage (AMU) and hygiene practices and the occurrence of antimicrobial resistance (AMR) profiles of Salmonella isolated from raw cow milk and its products. Two hundred samples were collected from dairy farms, milk vendors, and restaurants and analyzed using standard microbiological methods. Using the OmniLog system, Salmonella enterica was successfully identified. Then, the antimicrobial susceptibility was evaluated using the Kirby-Bauer disc diffusion technique. Data were analyzed using STATA version 14.2. Results Overall, 2% (n = 4) of the samples tested positive for S. enterica . Of the 4 isolates, 3 were identified in dairy farm samples, whereas 1 were isolated from milk vendors. However, no Salmonella was identified in cheese or yogurt samples obtained from the restaurants. Regarding the AMR profile, S. enterica isolates were resistant to amoxicillin (75%), streptomycin (75%), and tetracycline (50%). Resistant to two or more antimicrobials were identified in 75% of the isolates. Conclusion This study indicated contamination of cow milk and its products with S. enterica . Therefore, appropriate control measures, including awareness creation among personnel and improving hygienic practices at the milk value chains is recommended to mitigate cross-contamination.