Effect of a Saccharomyces cerevisiae Postbiotic Feed Additive on Salmonella Enteritidis Colonization of Cecal and Ovarian Tissues in Directly Challenged and Horizontally Exposed Layer Pullets

Abstract

Determining the efficacy of feed-additive technologies utilized as pre-harvest food-safety interventions against Salmonella enterica may be influenced by factors including, but not limited to, mechanism of action, experimental design variables, Salmonella serovar(s), exposure dose, route, or duration in both controlled research and real-world field observations. The purpose of this study was to evaluate the dietary inclusion of a Saccharomyces cerevisiae fermentation-derived postbiotic (SCFP) additive (Diamond V, Original XPC®) on the colonization of cecal and ovarian tissues of commercial pullets directly and indirectly exposed to Salmonella Enteritidis (SE). Four hundred and eighty commercial, day-of-age W-36 chicks were randomly allotted to 60 cages per treatment in two identical BSL-2 isolation rooms (Iowa State University) with four birds per cage and fed control (CON) or treatment (TRT) diets for the duration of study. At 16 weeks, two birds per cage were directly challenged via oral gavage with 1.1 × 109 CFU of a nalidixic-acid-resistant SE strain. The remaining two birds in each cage were thus horizontally exposed to the SE challenge. At 3, 7, and 14 days post-challenge (DPC), 20 cages per group were harvested and sampled for SE prevalence and load. No significant differences were observed between groups for SE prevalence in the ceca or ovary tissues of directly challenged birds. For the indirectly exposed cohort, SE cecal prevalence at 7 DPC was significantly lower for TRT (50.0%) vs. CON (72.5%) (p = 0.037) and, likewise, demonstrated significantly lower mean SE cecal load (1.69 Log10) vs. CON (2.83 Log10) (p = 0.005). At 14 DPC, no significant differences were detected but ~10% fewer birds remained positive in the TRT group vs. CON (p > 0.05). These findings suggest that diets supplemented with SCFP postbiotic may be a useful tool for mitigating SE colonization in horizontally exposed pullets and may support pre-harvest food-safety strategies.

Effect of a Bacillus subtilis plus Yeast Cell Wall Synbiotic on Salmonella Enteritidis Colonization in Ceca of Layer Pullets

“…In addition to the ileum and cloaca, cecal pouches are the preferred organs for SE colonization and establishment after it is ingested by chickens [35]. After an SE challenge, SE colonized the ceca of young layer pullets [21,26,29,30,36], layer pullets near sexual maturity [24,25,27,28], and adult laying hens [21][22][23]. In this study, orally infecting layer pullets with an SE dose of 6.3 × 10 7 CFU at 8 days of age resulted in colonization of the ceca, as evidenced by load and prevalence of SE in the ceca.…”

“…Mannan oligosaccharides (MOSs), fructo-oligosaccharides (FOSs), and galacto-oligosaccharides (GOSs) are among the more commonly employed prebiotics in animal and poultry research [17], and other new prebiotic technologies, such as mannabiose (MNB), which are derivatives of MOS, have been shown to be efficacious for use in controlling SE in poultry [20]. Bacillus probiotics [21][22][23] and MOS prebiotics [23][24][25][26][27] have been shown to reduce SE colonization in layer birds. In addition, Bacillus-based probiotics and yeast cell wall-based prebiotics are among the most used feed additives in poultry.…”

Salmonella Infection in Poultry: A Review on the Pathogen and Control Strategies

“…Choe et al reported that supplementing layer birds with soluble metabolite combinations of L. plantarum strains improved egg production performance, fecal population of LAB, and intestinal villi height and crypt depth [157]. Additionally, postbiotics derived from Saccharomyces cerevisiae fermentation reduced the cecal colonization of Salmonella in broilers and layer pullets, making them a potential preharvest intervention to enhance food safety and improve production performance [158,159].…”