Long-chain glucomannan supplementation modulates immune responsiveness, as well as intestinal microbiota, and impacts infection of broiler chickens with Salmonella enterica serotype Enteritidis

Abstract

The zoonotic pathogen Salmonella enterica serotype Enteritidis (SE) causes severe disease in young chickens. Restriction on antibiotic use requires alternative SE control strategies such as nutritional solutions to improve the resistance of chickens. In this study, chickens were fed long-chain glucomannan (GM) or standard diet and challenged with SE at seven days of age. During 21 days post-infection (dpi), we determined numbers and responsiveness of natural killer (NK) and T cells in ileum and spleen, and SE-specific antibody titers in serum. Microbiota compositions in ileum and caeca were determined, as well as correlations of these with numbers and function of immune cells. Some of the samples in the control group had numerically higher CFUs than the GM-treated group. In addition, the relative abundance of SE based on DNA assessment was significantly lower at 21 dpi upon GM supplementation. At 3 dpi, numbers of intraepithelial NK cells were significantly higher, while activation of intraepithelial NK cells (7 dpi), numbers of intraepithelial cytotoxic CD8+ T cells (14 dpi) and SE-specific antibodies (14 dpi) were numerically higher. Furthermore, relative abundance of the commensal lactic acid bacteria (LAB) significantly increased with GM supplementation post-infection. Higher relative abundance of streptococci was associated with reduced SE in ileal and caecal contents at 21 dpi. Relative abundance of streptococci negatively correlated with SE counts and positively correlated with NK cell activation and SE-specific antibodies, which suggests involvement of the commensal LAB in NK cell responsiveness. These results indicate that GM supplementation modulates the immune system, intestinal microbiota and impacts SE infection of young chickens.

Holistic Strategies to Control Salmonella Infantis: An Emerging Challenge in the European Broiler Sector

“…However, it appears that certain fractions of cereal grains can be a source of several β-glucans, which are also potentially fermentable, resulting in the antagonism of pathogens such as Salmonella [ 103 ]. Furthermore, recent studies have observed that other dietary fibers, such as long-chain glucomannan, can reduce the colonization of Salmonella in the intestines of birds, thereby reducing the excretion of the bacteria into the environment, while also stimulating the immune response of the animal [ 104 ].…”

Effects of Glucomannan Feed Additives on Large White Turkey Female Performance, Gastrointestinal Microbial Population, and Blood Corticosterone Levels in a Simulated Transport Challenge

“…Birds were fed either a control diet or diets with two different glucomannans at 0.02% or 0.20% inclusion levels. The inclusion levels of glucomannans were chosen based on the results from in ovo and in vivo broiler trials [13,14] and from previous studies with the same glucomannans on turkeys (non-published data). Glucomannans were labeled medium-chain glucomannan (MG) and long-chain glucomannan (LG) (Cargill Incorporated, Minneapolis, MN).…”

“…Glucommanans is considered a feed additive with prebiotic effects that can be produced by combining cereal-derived mannose units to create different types of water soluble fibers. Previous studies with poultry have shown that glucomannans may have a positive impact on growth through modulation of the immune system, can act as prebiotics impacting gut microbiota, and by interacting with specific binding sites of the intestinal mucosa trigger physiological state [10,13,14].…”