Effect of dietary concentration of xylitol on growth in male broiler chicks during immunological stress.

Two experiments were conducted to determine the effect of dietary xylitol concentration on growth performance, plasma (alpha1 acid glycoprotein (AGP), nitrite, and Fe concentration in male broiler chicks during immunological stress. Ten-day-old chicks were fed a corn-soybean diet containing 15% glucose and 6% xylitol or 15% xylitol with identical metabolizable energy and crude protein content for 12 d in Experiment 1. In Experiment 2, 12-d-old chicks were fed either the 15% glucose or 6% xylitol diet for 7 d. During the final 6 d of each experiment, half of the birds fed each diet were injected intraperitoneally with Escherichia coli lipopolysaccharide (LPS; 0127:B8) on Days 1, 3, and 5 and with Sephadex-G50 superfine on Days 2 and 4 to stimulate the immune system. The xylitol diets partially prevented reductions in body weight gain, feed intake, and feed efficiency caused by LPS and Sephadex injections, but the glucose diet did not. The injections of LPS and Sephadex increased plasma AGP and nitrite concentrations. Plasma AGP concentration on Days 2 and 6 in chicks fed the xylitol diets did not differ from that of chicks fed the glucose diet in both experiments. Nitric oxide production estimated by plasma nitrite concentration following immunological stress did not differ due to dietary treatments in Experiment 2. The LPS and Sephadex resulted in decreased plasma Fe concentration on Day 6 in Experiment 1 in chicks fed glucose but not xylitol. These results indicate that a beneficial effect of dietary xylitol on growth is obtained with 6% xylitol given to chicks 1 d before stimulating the immune system.