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Bovine milk and milk products may contain pathogens, antimicrobial resistant bacteria, and antibiotic residues that could harm consumers. We analyzed 282 gram-positive isolates from milk samples from dairy farmers and vendors in Haryana and Assam, India, to assess the prevalence of methicillin-resistant staphylococci using microbiological tests, antibiotic susceptibility testing, and genotyping by PCR. The prevalence of genotypic methicillin resistance in isolates from raw milk samples was 5% [95% confidence interval, CI (3-8)], with 7% [CI (3-10)] in Haryana, in contrast to 2% [CI (0.2-6)] in Assam. The prevalence was the same in isolates from milk samples collected from farmers [5% (n = 6), CI (2-11)] and vendors [5% (n = 7), CI (2-10)]. Methicillin resistance was also observed in 15% of the isolates from pasteurized milk [(n = 3), CI (3-38)]. Two staphylococci harboring a novel mecC gene were identified for the first time in Indian dairy products. The only SCCmec type identified was Type V. The staphylococci with the mecA (n = 11) gene in raw milk were commonly resistant to oxacillin [92%, CI (59-100)] and cefoxitin [74%, CI (39-94)], while the isolates with mecC (n = 2) were resistant to oxacillin (100%) only. All the staphylococci with the mecA (n = 3) gene in pasteurized milk were resistant to both oxacillin and cefoxitin. Our results provided evidence that methicillin-resistant staphylococci occur in dairy products in India with potential public health implications. The state with more intensive dairy systems (Haryana) had higher levels of methicillin-resistant bacteria in milk.

The consumption of milk contaminated with antibiotic-resistant bacteria poses a significant health threat to humans. This study aimed to investigate the prevalence of Enterobacteriaceae producing β-lactamases (ESBL, MBL, and AmpC) in cow and buffalo milk samples from two Indian states, Haryana and Assam. A total of 401 milk samples were collected from dairy farmers and vendors in the specified districts. Microbiological assays, antibiotic susceptibility testing, and PCR-based genotyping were employed to analyze 421 Gram-negative bacterial isolates. The overall prevalence of β-lactamase genes was 10% (confidence interval (CI) (7–13)), with higher rates in Haryana (13%, CI (9–19)) compared to Assam (7%, CI (4–11)). The identified β-lactamase genes in isolates were bla_CMY, bla_MOX, bla_FOX, bla_EBC, and bla_DHA, associated with AmpC production. Additionally, bla_CTX-M1, bla_SHV, and bla_TEM were detected as ESBL producers, while bla_VIM, bla_IMP, bla_SPM, bla_SIM, and bla_GIM were identified as MBL producers. Notably, Shigella spp. were the dominant β-lactamase producers among identified Enterobacteriaceae. This study highlights the presence of various prevalent β-lactamase genes in milk isolates, indicating the potential risk of antimicrobial-resistant bacteria in dairy products. The presence of β-lactam resistance raises concern as this could restrict antibiotic options for treatment. The discordance between genotypic and phenotypic methods emphasizes the necessity for comprehensive approaches that integrate both techniques to accurately assess antibiotic resistance. Urgent collaborative action incorporating rational and regulated use of antibiotics across the dairy value chain is required to address the global challenge of β-lactam resistance.

Antimicrobial resistance (AMR) in livestock is a growing One Health concern in India, where dairy is vital for nutrition and livelihoods. This study examined AMR in bacterial isolates from 256 cow milk samples in Assam and Haryana, including raw and pasteurized milk from farmers and vendors. AMR prevalence was high (90%) with no state-level differences. Dual AMR (Gram-positive and Gram-negative bacteria) occurred in 48% of samples, while multidrug resistance (MDR) was also 48%; dual MDR was less frequent (7%). Pasteurized milk showed significantly higher dual MDR (23%) compared to raw milk (6%, p = 0.023). No associations were found between AMR/MDR and herd size, mastitis history, antibiotic use, or farmer knowledge. These results highlight widespread AMR in milk, including vendor-sourced and pasteurized milk, and suggest complex systemic drivers beyond farm-level practices. Strengthened surveillance, with improved hygiene and handling during and after pasteurization, is critical to reduce AMR risks in the dairy sector.

Background: The rapid expansion of the poultry industry has positioned it as a key source of animal protein globally, with India ranking eighth in broiler meat production. However, intensification and increased input reliance have raised concerns over antibiotic overuse and antimicrobial resistance (AMR), particularly in low- and middle-income countries like India.

Methods: This study assessed the prevalence and resistance profiles of non-typhoidal Salmonella (NTS) and Escherichia coli (E. coli) in poultry environments (water, fecal, feed, and litter samples) across two Indian states, Assam and Karnataka. Antibiotic residues in meat and feed samples were also tested.

Results: Of 283 samples, NTS and E. coli were detected in 32% (90/283) and 56% (158/283), respectively. Prevalence varied significantly by region, with Karnataka reporting higher NTS [44% (59/133)] than Assam [21% (31/150)]. Both pathogens were detected in treated water used in poultry, suggesting ineffective sanitation. Predominant Salmonella serovars included Typhimurium, Kentucky, and Infantis, many of which showed multidrug resistance (MDR), including to critical fluoroquinolones. Alarmingly, carbapenem-resistant E. coli strains were also identified.

Larger flock sizes were associated with a higher risk of MDR in both NTS and E. coli, suggesting a possible link between production intensity and resistance, though not statistically significant. Multivariable analysis showed higher odds of resistant Salmonella in Karnataka, and sock samples were particularly effective for detection. E. coli resistance was widespread, with no individual predictor reaching significance in multivariable models. No antibiotic residues were found in tested samples.

Conclusion: This study is among the first in India to report fluoroquinolone resistance and MDR in poultry-associated zoonotic NTS serovars across diverse matrices, with serious implications for food safety and public health. Although limited in scale, the absence of antibiotic residues is reassuring. These findings provide critical insight into the AMR landscape of India’s poultry value chains and underscore the urgent need for integrated, One Health based strategies to address AMR in poultry systems and protect public health and food safety.

Traditional fermented food products are often connected to various indigenous tribes and thus vary due to ethnicity, geography, and natural resource availability. The indigenous tribes from India greatly rely on fermentation processes for food preservation, flavor, and nutrition. Fermented foods can provide health benefits but also pose risks from harmful microbes and contaminants that grow in the food due to poor hygiene. In this study, we identified lactic acid bacteria (LAB) in fermented food collected from Northeast India, assessed their beneficial properties, and highlighted the risk from food pathogens that have antimicrobial resistance traits. A total of 113 different samples of fermented food products were collected from the local markets of five Northeastern Indian states (Nagaland, Manipur, Meghalaya, Arunachal Pradesh, and Sikkim). Standard laboratory methods were used to isolate LAB and determine their probiotic properties, conduct coliform counts, and isolate presumptive staphylococci from the fermented food samples. Antimicrobial susceptibility was determined by using the BD-Phoenix 100 automated system. We isolated 30 LAB with probiotic potential. The average aerobic colony count in different fermented food was 4.4-7.7 log center dot cfu/g, while coliforms were present in 43% (49/113, 95% (CI 34-53)) of the food samples, indicating low-hygiene levels. Additionally, some food samples contained staphylococci with phenotypic antibiotic-resistance markers (MRS, HLMUP, BLACT, and STAMLS). This study indicates that probiotic bacteria could be present in traditional fermented food products of Northeast India, but contamination with staphylococci and other bacterial pathogens with antibiotic resistance traits could put the health of consumers at risk.