Effects of whole wheat incorporated into pelleted diets on the growth performance and intestinal function of broiler chickens

• Whole wheat in the diet may improve feed conversion efficiency in broiler chickens.
• Upper part of digestive tract is stimulated by whole wheat increasing gizzard weight.
• This stimuli result in higher activities of pancreatic enzymes in the small intestine.
• Intestinal viscosity and histological properties of small intestine are not influenced.
• Whole wheat inclusion in the diet decreases feeding costs by reducing grinding.

An experiment was carried out to study the effect of postpelleting dietary inclusion of whole wheat seed at the expense of ground wheat on the performance and gastrointestinal characteristics of broiler chickens. After the starter period three different diets were fed. Besides control diets that did not contain wheat seed, two other diets with different wheat seed contents were composed. Treatment A contained 5, 10, and 15%, treatment B contained 5, 20 and 30% wheat seed, respectively, in grower I, grower II and finisher phases, respectively. Body weight and feed consumption of chickens were measured at the end of each phase. At 40 days of age 12 chickens were slaughtered from each treatment. Carcass parameters, enzyme activities of digesta and histological structure of the small intestine were determined.No significant differences were found between the treatments in the weight of the chickens. Chickens fed the diet containing lower percentages of whole wheat (treatment A) showed significantly better feed conversion ratio than chickens of the control group and the group fed the higher level of whole wheat (treatment B), respectively. No significant differences were found between the treatment groups in the relative carcass, breast fillet, thigh and abdominal weights. Compared to the control group, wheat seed feeding increased gizzard weight by 46.2 and 62.2% in treatment A and treatment B, respectively. Relative to the control group, higher trypsin, α-amylase and lipase activities were detected in the jenjunal digesta when the diets contained whole wheat. Dietary treatments did not cause any differences in the viscosity of the intestinal contents and in the histological structure of the small intestine.