Salmonellosis and Related Risk Factors in Broiler Flocks in Mazandaran Province, Northern Iran

Background: Prevention of foodborne pathogens is essential to control infectious diseases; Salmonella spp. is referred to as the most common causative agent of foodborne illnesses. Objectives: The current study aimed to determine the prevalence of Salmonella enterica subsp. enterica in broiler flocks in Mazandaran province, north of Iran and find the potential risk factors including: age, size of flock, strain, season, vaccination program and use of antibiotics. Materials and Methods: From March 2012 to December 2013, a total of 50 flocks were selected in slaughterhouse and 20 cloacal samples were collected from each flock. Every five samples were pooled and investigated for Salmonella spp. using polymerase chain reaction (PCR). Results: Thirteen flocks out of 50 (26%) were positive for Salmonella species. Chances of Salmonella spp. detection was higher in flocks with lower age (P = 0.41). Increasing flock population was associated with increased chance of Salmonella spp. isolation (P = 0.21). The risk of salmonellosis in broiler flocks was increased when no antibiotics were given to day-old chicks. There was no significant difference (P = 0.30) in the prevalence of salmonellosis among different broiler strains. Conclusions: In the current study, six risk factors were assessed for Salmonella spp. contamination in broiler flocks. Some of these factors contributed to the risk of salmonellosis in broiler flocks.