Occurrence of Salmonella spp. in backyard poultry in Bosnia and Herzegovina

Background: Infected poultry is one of the most important reservoirs of Salmonella. Aims: The investigation presented here was conducted to examine the occurrence of Salmonella in fecal samples among selected flocks of backyard poultry in Bosnia and Herzegovina (B&H). Methods: Isolation and identification of Salmonella was performed in accordance with BAS EN ISO 6579/AMD 1:2007. When genus Salmonella was confirmed, the determination of the antigenic formula of Salmonella isolates was performed in accordance with BAS CEN ISO/TR 6579-3:2015. After that, Salmonella serotypes were subjected to antibiotic susceptibility testing using EUVSEC sensititre microtiter plates impregnated with different concentrations of antibiotics. At the end, real-time PCR was used to detect extended spectrum beta-lactamases (ESBL) and carbapeneamase encoding genes (bla(TEM), bla(SHV), bia(CTX-M), bla(CMY), bla(KPC), bla(NDM), biao(XA-48), bla(VIM) and bla(GES)). Results: Salmonella spp. was detected in pooled feces from four backyards, housed by chickens only. Three isolates were confirmed by slide agglutination as serotype Enteritidis and one as serotype Typhimurium. Antibiotic susceptibility testing by microdilution did not reveal phenotypical resistance among these four isolates. Real-time PCR used to detect ESBL and carbapeneamase encoding genes revealed the bia(TEM) gene in one S. Enteritidis isolate. Conclusion: Data presented in this study provide further evidence on the circulation of different Salmonella serotypes in backyard poultry in B&H. These findings emphasize the potential role of backyard poultry in the epidemiology of salmonellosis and the risks it poses for keepers, consumers, and general public health.