An evaluation of the effect of sodium bisulfate as a feed additive on Salmonella enterica serotype Enteritidis in experimentally infected broilers

The colonization of broiler chickens with Salmonella can pose serious health and economic risks for both consumers and the poultry industry. Because colonization with Salmonella can lead to subsequent contamination of chicken carcasses during processing, preemptive control measures should include the reduction of this pathogen in chickens before slaughter. In this study, we evaluated the effect of sodium bisulfate, a potential antimicrobial feed additive, on Salmonella colonization of experimentally infected broiler chickens. Two hundred and forty 1-d-old chickens were infected orally with Salmonella enterica serotype Enteritidis and divided into 4 groups (each comprised of 60 chickens). Three groups received different concentrations of sodium bisulfate integrated into their feed, while the feed of the fourth group (positive control) was not treated. At time points before the broilers' slaughter age, different organs/tissues (liver, spleen, cecum, and bone marrow) and feces were aseptically collected and tested for the occurrence and density of Salmonella Enteritidis. Our results show that at 3 d postinfection, high colonization with Salmonella Enteritidis was detected and affected all tested tissues and fecal samples. Although colonization decreased across time, Salmonella Enteritidis persisted in the cecum, feces, spleen, and bone marrow, but not in the liver, until slaughter age. Furthermore, the addition of sodium bisulfate to the feed did not significantly reduce Salmonella Enteritidis numbers in infected chickens or affect the shedding of the pathogen.