Identification of Antimicrobial Resistant (AMR) Gene in Salmonella sp isolated from Broiler Chicken at Chattogram Area

Abstract

Globally, antimicrobial resistance (AMR) is a public health concern, since antibiotics are among the most prescribed classes of drugs in humans and animals. Random use of antimicrobials in the poultry industry is considered as a contributing factor for AMR that can jeopardize human health through the potential dissemination of AMR pathogens. It is noteworthy that Salmonella is one of the bacterial groups considered to be of high priority in surveillance programs in the food chain and infectious diseases in poultry. Information on the circulation of Salmonella strains at the commercial poultry farm level is limited in many parts of the world. The present study aimed to determine the prevalence and stereotyping of Salmonella strains circulating in the broiler farm environment with their detailed AMR profiling. Pooled cloacal samples were collected randomly from commercial broiler farms in Chattogram district, Bangladesh. Then the standard bacteriological procedure was followed to isolate Salmonella sp, and identification was confirmed by the basis of morphology, cultural characters, and genus-specific polymerase chain reaction (PCR). After phenotypic characterization of the resistance profile against commonly used antibiotics by disc diffusion technique, all strains were screened by PCR for some selected resistance genes. Out of the 105 samples, Salmonella sp was isolated and identified from 8 samples. In antimicrobial sensitivity testing, 100% isolates showed resistance to ampicillin and amoxicillin, and 87.5% to gentamycin followed by tetracycline, and ciprofloxacin (75%), doxycycline (50%), Trimethoprim/Sulfamethoxazole, and Ceftriaxone (25%). The results of PCR assays revealed that all the eight isolates were carrying the tetA gene, the tetB and 16.67% the tetC gene. The prevalence of the isolates bearing the Sul-I gene, blaTEM, blaCTX-M were 100%, 87.5 %, and 50 %, respectively. The present study was conducted to find out the prevalence of poultry Salmonella in broiler chickens and to find out that there is a great risk to securing healthy poultry products due to the circulation of the multi drug resistant (MDR) Salmonella sp.