Phenotypic Antimicrobial Resistance Patterns in Salmonella typhimurium and Enteritidis Strains Isolated from Human, Food, and Environmental Samples of Broiler Meat Production Chain in Punjab
The emergence of antimicrobial resistance is a growing public health issue worldwide due to extensive use in agriculture, food, and veterinary medicine. The rate of antimicrobial resistance varies with different antibiotics and serotypes but Salmonella enterica serovar Enteritidis is one of the most widespread serotypes which is comparatively more susceptible to antimicrobial resistance followed by S. Typhimurium. A total of 71 Salmonella strains (S. Typhimurium, n=45; S. Enteritidis, n=26) isolated from humans, food and the environment were used in the study. Both isolates were confirmed through PCR by targeting their specific spy and sdf genes respectively. Kirby-Bauer disc diffusion method was used to determine antimicrobial susceptibility against 10 antibiotics used. An exponentially high level of resistance was found in S. Typhimurium strains. The highest level of resistance was found against amoxicillin (97.78%) followed by tetracycline (95.56%), gentamicin (93.33%), trimethoprim (86.67%), streptomycin (84.44%), nalidixic acid (77.78%), sulphafurazole (64.44%), ampicillin (62.22%), chloramphenicol (46.67%) and least resistance was found against ciprofloxacin (31.11%). Four penta MDR (ACSSuT) and two tetra MDR (ASSuT) resistance patterns were found S. Typhimurium strains. In S. Enteritidis strains, a high level of resistance was found against sulphonamides and streptomycin (92.31%) with the least resistance against ciprofloxacin (11.54%). Two penta MDR (ACSSuT) and six tetra MDR (ASSuT) resistance patterns were found. The presence of high antimicrobial resistance in zoonotic S. Typhimurium and Enteritidis in the broiler meat production chain is alarming. Immediate action and appropriate measures are required to control over the counter and irrational use of antibiotics both in poultry and humans. © 2021 Friends Science Publishers