Study on phenotypic characteristics of Salmonella gallinarum and Sallmonella pullorum isolates based on biochemical and antimicrobial susceptibility tests in Iran

Salmonellosis is a very important disease of avian species because of its huge economic impact, worldwide distribution and difficulty posed in its control. Fowl typhoid and pullorum disease, is caused by Salmonella enterica subsp enterica serovar Gallinarum biovar Gallinarum and Pullorum. The purpose of this study was to investigate the biochemical characteristics and antimicrobial susceptibility of Salmonella gallinarum and Salmonella pullorum. A total of 13 Salmonella isolates, identified by biochemical tests and specific antisera including Salmonella gallinarum (n=10) and Salmonella pullorum (n=3). All were found to be susceptible to gentamicin. Also 7 (53.8 %), 6 (46.1%) and 5 (38.4%) isolates were resistant to streptomycin, cephalexin and nalidixic acid respectively. Multidrug resistance to three or more antibiotics was observed in 6 (46.1%) isolates and overall 9 antibiotic resistance patterns were recorded. The results showed that poultries as a source of antimicrobial resistance could pose a serious risk to public health via food chain transfer. Hence more epidemiological surveillance programs and antibiotic susceptibility investigations are advised.