Abstract
Abstract
This experiment was conducted in the poultry farm of the Animal Production Department/College of Agriculture/Anbar University, from 8/12/2019 until 23/3/2019 for 6 weeks. The experiment aim to compare the addition of two different levels of chitosan and a group of antibiotics to the corn-soybean diet and their effect in physiological and microbial performance at 42 days. The experiment included T1 (control of corn diet without any addition), T2 (0.2 g oxytetracycline/kg corn diet), T3 (1 g chitosan/kg corn diet), and T4 (2g chitosan/kg corn diet). In the experiment, 144 birds (Ross) at the age of 7 days were used with an average weight of 40 g. The chicks were distributed randomly to 4 treatments, with 3 replicates, and in each repeater, 12 birds. The results of the physiological parameters indicated that there were T4 increased significantly (P≤0.05) compared to other treatments in H/L and monocyte count at 42 days, while the results showed that were no significant differences in the biochemical characteristics of blood. As for the tissue of Jejunum, treatment T3 was significantly (P≤0.05) superior to the rest of the treatments in the height, thickness of villi and depth of crypts over the experimental treatment. There was a significant decrease (P≤0.05) for the T3 and T4 compared to the T1 control treatment on the total bacterial count and colon bacterial count.