Aflatoxin Effect on Humoral and Mucosal Immune Responses Against Infectious Bronchitis Vaccine in Broilers

Abstract

The aflatoxin effect on humoral and mucosal immunity against infectious bronchitis (IB) vaccine was studied in 225 one-day-old chicks. The chicks were divided in 3 equal groups. Treatment groups included group A: chickens fed a basal diet, and group B: chickens fed 3 ppm productive aflatoxin in a basal diet. The chickens in groups A and B were vaccinated against IB (at one and 10 days old) by H120 live attenuated vaccine. For group C, chickens did not receive aflatoxin and were not vaccinated against IB. All chickens received experimental diets from 3 to 28 days old, continuously. At 28 days old, all chickens were slaughtered. After blood sampling, serum was prepared for measuring serum IgG titer against IB vaccine by Elisa method. Moreover, the heads were collected for nasal-tracheal lavage for assaying IgA against IB vaccine in mucosa of respiratory tract. The measurement of serum IgG against IB vaccine was done by commercial IBV ELISA kit. The assaying of mucosal IgA against IB vaccine was done by IBV ELISA plate and specific goat anti-chicken IgA. Results indicated that the chickens receiving aflatoxin showed less serum IgG and mucosal IgA titers than the others. Therefore, it seems that aflatoxin can affect mucosal immunity in the upper respiratory tract as well as the systemic immune response against IB vaccine.