The Effect of Different Levels of Aflatoxin B1 on Intestinal Length, Blood Parameters and Immune System in Broiler Chickens

This study was conducted to investigate the toxic effects of Aflatoxin on the immune system and blood parameters of broilers. For these purposes، 120 Ross 308 broiler chicks were used in a completely randomized design with 3 treatments، 4 replicates and 10 chicks in each unit. The chickens were reared for 35 days on the ground. The treatments were as follows: 1- control (no dietary Aflatoxin B1)، 2- diets containing 250 ppb of Aflatoxin B1 and 3- diets containing 500 ppb of Aflatoxin B1. The minimum length of the ileum and intestine belonged to chicks receiving 500 ppb Aflatoxin level. After the blood samples were taken، total protein، albumin، bilirubin، glucose، uric acid، calcium، phosphorus، and AST، ALT and γ-GT were measured. The titration tests of Newcastle and influenza disease، in two steps (25 and 34 days) were performed. At the age of 25 days، before administering the Newcastle-influenza vaccine، the blood samples were collected from two chicks in each group. The HI antibody titers against Newcastle and influenza were determined in them. In addition، in 34 days of age، blood samples were taken from the first stage chickens and the antibodies were measured again. No significant changes were observed in the levels of calcium، phosphorus، albumin and total protein in the serum of experimental broilers compared with birds receiving the basal diet. As the levels of Aflatoxin B1 increased from 250 to 500 ppb in feed، the serum levels of glucose، total bilirubin and AST also increased. In contrast، the level of direct bilirubin decreased significantly. HI titer against influenza and Newcastle disease in the second stage (34 days) showed a significant decrease compared to the basic treatment. The findings also evinced that Aflatoxin causes changes in the blood parameters، kidney and liver damages and decreased immune functions against Newcastle disease and influenza in broiler chickens.