Influence Of b-Glugan On Nonspecific Immunity And Growth Performance In Weanling Pigs

Kansas State University Swine Research. Three experiments, using 344 pigs, were conducted to evaluate the influence of b- glucan (MacroGardTM-S) on neutrophil and macrophage function, resistance to Streptococcus suis challenge, and growth performance in weanling pigs. b-glucan, when fed at inclusion rates of .05 and .1%, did not influence neutrophil or macrophage function or increase overall growth performance. Similarly, .025% b-glucan did not alter neutrophil or macrophage bactericidal activity or production of superoxide anion. However, diets containing .025% b-glucan increased average daily gain, average daily feed intake, and pigs weights and decreased plasma haptoglobin levels on d 21. Unfortunately, pigs fed a diet containing .025% that exhibited increased growth performance were more likely to die after challenge with S. suis. These data suggest the existence of a complex interaction involving growth performance and resistance to S. suis in pigs fed .025% b-glucan. The interaction should be investigated further.