Dietary energy source and supplements in broiler diets containing defatted rice bran

Increasing the concentration of defatted rice bran (DRB) in the diet will increase the concentration of energy sources such as fat (oil) and carbohydrate because DRB contains relatively lower energy compared with the most common energy source, grain (corn). An experiment with broiler chicks was conducted to determine the influence of a high level of fat versus a high level of carbohydrate on the nutritional value of a diet containing 30% DRB. In order to improve the digestibility of fat and to anticipate the negative effect of increasing the concentration of nonstarch polysaccharide in the DRB during the early age of broiler chicks, two supplements [a bile salt (sodium taurocholate) or a fiber-degrading mixture of enzymes (Grindazyme GP 5000)] were included. The protein and fat digestibilities and MEn value were greater with high-fat diets compared with high-carbohydrate diets. These effects of the high-fat diet were reflected in superior growth and feed intake of chicks from 1 to 14 d of age. The supplementation of the DRB diets with the bile salt was of greater benefit for chick performance than the inclusion of a mixture of fiber-degrading enzymes, especially with high-fat diets.