|Lowry, Virginia - TX A&M UNIVERSITY|
|Farnell, Morgan - INSTITUTE ANIMAL HEALTH|
|Ferro, Pamela - TX A&M UNIVERSITY|
|Bahl, Arun - IMMUDYNE, INC.|
Submitted to: International Journal of Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 14, 2004
Publication Date: February 15, 2005
Citation: Lowry, V.K., Farnell, M.B., Ferro, P.J., Swaggerty, C.L., Bahl, A., Kogut, M.H. 2005. Purified beta-glucan as an abiotic feed additive up-regulates the innate immune response in immature chickens against Salmonella enterica serovar enteritidis. International Journal of Food Microbiology. 98:309-318. Interpretive Summary: During the past two decades, many studies have shown a large percentage of poultry products are contaminated with salmonellae. Salmonella, a bacterial pathogen, can cause food poisoning in humans which may result in death. Baby chickens are susceptible to Salmonella during the first week of life because their immune system (ability to fight off infection) is not yet fully developed. Our laboratory has shown that heterophils, a white blood cell found in chickens, may be stimulated by various methods to help fight off infection in baby chicks when the immune system is mature. The purpose of this experiment was to determine if a purified form of beta-glucan (a substance isolated from the cell wall of yeast) incorporated into the feed of baby chicks would stimulate the immature heterophil to eat and kill the salmonella in baby chicks the first week of life and help fight off salmonella infections in the liver and spleen. The results from these experiments showed baby chicks fed the beta glucan feed had fewer Salmonella contaminated livers and spleens than chicks that did not receive the beta glucan feed. The heterophils from chicks fed the beta glucan feed also killed more salmonella than the heterophils from chickens that were not fed beta glucan.
Technical Abstract: Functionally, the innate immune system of immature chickens is inefficient during the first week post-hatch. Pathogens, such as Salmonella enterica Serovar Enteritidis (SE), are able to invade various tissues due to this immunological inefficiency of the immature chicken. The objective of the present study was to evaluate the effect of purified beta-glucan as an immunomodulator of the innate immune response, specifically the heterophil. The functional efficiency of heterophils isolated from immature chickens fed a beta-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 beta-glucan ration (P<0.05). To our knowledge this is the first report of a purified beta-glucan feed additive significantly up-regulating the functional abilities of heterophils isolated from immature chickens against an invading pathogen, SE.