Antibiotic Resistance Profiles of Lactic Acid Bacteria Isolated from Dairy Products in Lahore, Pakistan

Antibiotic resistance (AR) among lactic acid bacteria (LAB) in dairy products is an emerging concern due to their potential role as reservoirs of transferable resistance genes. While LAB are generally recognized as safe and widely used in fermentation, resistant strains may compromise food safety and public health. Objectives: To isolate and identify lactic acid bacteria (LAB) from popular dairy products (raw milk, yogurt, and cheese) in Lahore, Pakistan. Methods: This laboratory-based cross-sectional experimental study included a total of 60 dairy samples (raw milk, yogurt, and cheese) collected from local markets in Lahore, Pakistan. LAB were isolated and identified using standard microbiological and molecular methods, and their susceptibility to commonly used antibiotics was evaluated. Results: LAB were recovered from the majority of samples, predominantly Lactobacillus spp. Resistance was most frequently observed against tetracycline, erythromycin, and ampicillin, whereas vancomycin and chloramphenicol showed lower resistance levels. The multiple antibiotic resistance (MAR) index was used to estimate “resistance pressure,” referring to the extent of environmental or selective exposure to antibiotics that may promote resistance development. Overall, a subset of isolates exhibited multidrug resistance, indicating potential public health implications. Conclusions: This study highlights that LAB isolated from dairy products in Lahore harbor resistance to clinically important antibiotics. Although LAB are beneficial in food production, their potential role as reservoirs of resistance genes calls for monitoring programs and responsible antibiotic practices in dairy farming.