Effects of a synbiotic combination of Bacillus subtilis and yeast cell wall-derived glucomannan on cecal colonization of Salmonella Enteritidis in layer chickens

Abstract

Salmonella Enteritidis ( SE ) has been a major foodborne concern associated with poultry and poultry products. Direct-fed microbials ( DFM ), such as Bacillus subtilis strains , and mannan-oligosaccharides ( MOS ) added into poultry feed have emerged as an alternative approach to antimicrobials to reduce Salmonella colonization in chickens. This study was conducted to evaluate the effect of a synbiotic feed additive product (BacPack Q1+1) combining a selected Bacillus subtilis strain and yeast cell wall-derived MOS on SE colonization in the ceca of Hy-line W36 pullets. Day-old chicks were raised in cage units and orally challenged at 3 wk-of-age with a nalidixic acid resistant SE strain at a dose of 1.6 × 10 9 colony forming units ( CFU ) per bird. SE colonization was assessed by enumeration of SE in cecal pouches at 7, 10 and 13 days postinfection ( dpi ). SE was not detectable in the ceca of 68% of synbiotic supplemented pullets compared to 36% of the controls at 13 dpi ( P = 0.049). The findings of this study suggest that synbiotic combinations of DFM and prebiotics could be a useful tool for reducing the prevalence of Salmonella in layer chickens.