Purified β-glucan as an abiotic feed additive up-regulates the innate immune response in immature chickens against Salmonella enterica serovar Enteritidis

Functionally, the innate immune system of immature chickens is inefficient during the first week posthatch. This immunological inefficiency enables pathogens such as Salmonella enterica serovar Enteritidis (SE) to invade and colonize the visceral organs of immature chickens. The objective of this study was to evaluate the effect of purified β-glucan as an immunomodulator of the innate immune response. β-glucan, as a feed additive, significantly provided protection against SE organ invasion in young chickens (P<0.05). The functional efficiency of heterophils isolated from neonatal chickens fed a β-glucan ration was significantly (P<0.05) up-regulated when compared to heterophils isolated from chickens fed a control ration as determined with an array of functional assays. Phagocytosis, bactericidal killing, and oxidative burst were significantly increased in heterophils isolated from chickens fed the purified β-glucan ration (P<0.05). To our knowledge, this is the first report of a purified β-glucan feed additive significantly decreasing the incidence of SE organ invasion in immature chickens and up-regulating the functional abilities of heterophils isolated from immature chickens against an invading pathogen, SE.