Isolation and molecular characterization of multidrug-resistant Salmonella, Shigella and Proteus from domestic birds

Abstract

The increase in multidrug-resistant enteric bacteria, especially Salmonella, Shigella and Proteus in poultry has become a significant public health threat. Therefore, this work was aimed to investigate whether domestic birds have a role in the emergence and transmission of multidrug-resistant (MDR) bacteria in Taif province. Salmonella, Shigella and Proteus were isolated from different types of healthy domestic birds (n=42) collected from different places. Bacterial isolates were recovered from cloacal swabs of birds by non-selective and selective pre-enrichment technique. One hundred and sixty six bacterial isolates were screened for antibiotic susceptibility such as Cefaclor, Oxacillin, Ampicillin, Chloramphenicol, Cephalexin, Neomycin, Colistin, Ciprofloxacin, Oxytetracycline, Norfloxacin, Lincomycin, Gentamycin, Amoxicillin, Enrofloxacin and Piperacillin. The MDR bacterial isolates were identified using morphological, biochemical characteristics, and confirmed by API 20E strips, serological tests and 16S rRNA analysis. Forty-eight percent of the collected birds were positive for drug-resistant pathogenic bacteria including Salmonella, Shigella and Proteus. Phenotypic characterization was proved by PCR amplification of invA and mdh genes. The MDR bacterial isolates were found to harbour the plasmid-encoded multi-drug resistance. These results revealed that poultry might serve as a reservoir of multidrug-resistant Salmonella, Shigella and Proteus, and could be a possible mean of distribution of these pathogens to human.