Most commercially available beta-glucans are derived from yeast, but research on algae-derived beta-glucan in pigs is limited, according to a research abstract published in the most recent online edition of Animal Feed Science & Technology.
Therefore, researchers Kwangwook Kim, Amy Ehrlich, Vivian Perng, Jennifer A. Chase, Helen Raybould, Xunde Li, Edward R. Atwill, Rose Whelan, Adebayo Sokale, Yanhong Liu from the University of California-Davis and Evonik Corp. conducted an experiment to investigate the influence of dietary supplementation of algae-derived beta-glucan on diarrhea, gut permeability and immune responses of weaned pigs experimentally infected with a pathogenic Escherichia coli.
Kim et al. used 36 weaned pigs that were individually housed in disease containment rooms and randomly allotted, 12 pigs per treatment, to one of three dietary treatments: a control diet and two additional diets containing either 54 or 108 mg/kg of algae-derived beta-glucan. The experiment lasted 17 days — five days before and 12 days post-inoculation, the researchers said.
They inoculated the pigs with F18 E. coli, which contains heat-labile toxin, heat-stable toxin b and shiga-like toxin 2.
According to Kim et al., inclusion of a high dose of the algae-derived beta-glucan reduced (P < 0.05) the frequency of diarrhea (29.01% versus 17.28%) for the entire experimental period, which was likely due to reduced gut permeability and increased expression of gut barrier function genes in the jejunal mucosa of E. coli-challenged pigs.
The researchers also reported that beta-glucan supplementation also reduced (P < 0.05) levels of white blood cells, neutrophils, serum tumor necrosis factor-alpha, cortisol and haptoglobin and down-regulated (P < 0.05) the expression of several immune genes in the ileal mucosa of E. coli-challenged pigs compared with pigs on the control diet.
Kim et al. concluded that in-feed supplementation of an algae-derived beta-glucan alleviated diarrhea in pigs infected with F18 E. coli by enhancing gut integrity. Feeding beta-glucan also boosted host immune response against E. coli infection, they added.