Applied Food Research (Dec 2024)
Molecular detection and antimicrobial resistance profile of Salmonella isolated from humans, animals, abattoir equipment and environment
Abstract
Abattoir environments and poor slaughtering practices could serve as source of contamination with Salmonella species and their antimicrobial resistant genes, thereby affecting the animal-origin food system, and public health. This study aimed to isolate, and molecularly detect Salmonella species from humans, slaughtered animals, and from slaughtering equipment and environment, as well as to assess antimicrobial resistance profile of Salmonella isolates. A cross-sectional study was conducted at three abattoir settings, from September 2020 to February 2021. A total of 240 pooled swab samples were collected from the hands and cloths of abattoir workers, slaughtering areas, knives and from carcass; including water samples. Bacteriological techniques were employed to isolate presumed Salmonella species; while conventional and multiplex polymerase chain reactions (PCRs) were performed to confirm the genus Salmonella, Salmonella Enteritidis and S. Typhimurium. The Kirby-Buaer disk diffusion method was used to test antimicrobial susceptibility of confirmed Salmonella isolates. Based on bacteriological and biochemical tests, an overall 9.2 %(22/240) of Salmonella species were isolated, out of which 40.9 %(9/22) were found containing histidine transport operon gene. Among the nine Salmonella isolates, eight, six, six, five, and four isolates were found resistant to ampicillin, cefoxitin, tetracycline, Co-trimoxazole, and doxycycline hydrochloride, respectively. Furthermore, six of the Salmonella isolates showed multidrug resistance. The study showed presence of potential contamination of abattoir settings with antimicrobial resistant Salmonella isolates. With existing poor hygiene and sanitation practices, this might indicate risks for people consuming meat and for animals having access to contaminated environments.
