The effect of feed characteristics (pellet and mash) and nutrient requirements on the broiler performence

The experiment was conducted with broiler chicken to evaluate the effects of pelleted and mash diet on performance and morphology of the small intestinal wall and the microbial activity. The birds were housed in floors pens. The rearing place was located with the controlled temperature and humidity. Experiment was distributed in a completely randomized design for factorial experiment (2*2*2) with 8 replication or 32 observations and each treatment group was allotted at random to 8 pens with 25 birds each. Fore there 1600 day-old male Ross-308 broiler chicks were used. The diet was conducted to be adequate in all nutrients according to the National Research Council (1994). The experimental diets were fed for periods of 21 and 42d (1 to 21 and 22 to 42 days of age). At the end of each week chicks were weighted individually. Feed consumption and feed conversion were determined for each pen. The diets (pelleted and mash) were fed ad-libitum: water was also available ad-libitum. After termination of the performance trial, 4 randomly selected birds per pens (8 birds per treatment group) were killed. After sacrifice, the small intestine was removed immediately and samples 3 centimeter in length were taken from the intestinal wall, 15 centimeter distal of the Meckel, s diverticulum, for measuring morphological characteristics. In addition, samples of the digesta of the ileum were taken from measuring the bacterial counts. The results of experiments showed that pelleted diet significantly improve body weight of broiler chicks for first to six weeks of age perfectly compared to mash diet. Therefore, pelleted diet was not significantly effect on the feed intake of broiler chicks except at first week of age. However, pelleted feed significantly reduce feed conversion ratio (FCR) at the 42d of age. Microbial activity in the ileum, particularly that of the entercocci, estaphilococcus, coliforms, bifidobacterium, lactobacillus, bacteroides, total anaerobics, clostridia, total aerobic, was not increased significantly with dietary as pelleted and mash forms. The diet as pelleted affected morphology of the intestinal wall and significantly increased the number of goblet cells, villus length, villus width, crypt depth and villus length/crypt depth (µm). Results of the present study indicated that pelleted of diet changes morphology and of the small intestinal wall and improve performanse.