Effect of lactose and dried whey supplementation on growth performance and histology of the immune system in broilers.

The objective of this study was to evaluate the effect of lactose and dried whey supplementation as dietary component on growth performance and histology of lymphoid organs and ileum in broilers. A total of 480 day-old chicks were utilised for 42 days. Animals were assigned randomly to one of three treatments: control, lactose (2.5%), and dried whey (3.85%). Body weight was greater for animals supplemented with lactose or dried whey than for those not supplemented. There were no effects of treatments on feed intake and feed efficiency. In general, the effects of lactose or dried whey supplementation on histology of lymphoid organs and ileum were variable. Plasma cell counts were lower for animals supplemented with lactose than for those supplemented with dried whey. However, the length of intestinal villi during the starter period was greater for experimental groups than for control group.