Colonization of Salmonella Enteritidis (SE) in ceca and ovaries, after SE challenge, in Salmonella vaccinated commercial layer hens fed Saccharomyces cerevisiae components

Feed additives in egg layer diets have become an important tool in preventing the colonization of pathogens, such as Salmonella Enteritidis (SE), that cause foodborne illness in humans who consume eggs. Saccharomyces cerevisiae derived yeast cell wall, hydrolyzed yeast, and yeast culture contain mannan oligosaccharides that prevent SE from attaching to the intestinal wall and colonizing in the gastrointestinal tract. This trial was conducted to evaluate the efficacy of hydrolyzed yeast plus yeast culture (Cascade) and yeast cell wall plus hydrolyzed yeast (Naverde TM ) at preventing colonization of SE in ceca and ovaries of Salmonella vaccinated, peaking Hy-line brown layers, as well as to determine the effect of SE challenge on intestinal permeability. At 29 weeks, following a four-week adaptation to dietary treatments, layers were challenged with SE (10 9 cfu/mL) via oral gavage. Ceca and ovaries were collected seven-days post challenge to determine Salmonella prevalence and load. Also, at seven-days post challenge, layers were orally administered FITC-d, and a blood sample was collected to determine gut permeability. Compared to the control layers, layers fed either Cascade or Naverde had numerically lower ceca Salmonella loads (94.8 vs. 10.5 or 10.5 CFU/g and 0.441 vs. 0.170 or 0.133 log CFU/g, respectively). However, using the established challenge model and sampling protocol, Salmonella was not detected in the ovaries. The SE challenge did not have an effect on gut permeability. Therefore, Saccharomyces cerevisiae derived yeast cell wall, hydrolyzed yeast, and yeast culture could help to reduce Salmonella colonization in Salmonella vaccinated laying hens.