Evaluation of Mucosal Immunity in Chickens Vaccinated With Oral Pellet Newcastle Disease Vaccine

Abstract The Newcastle disease outbreak in chickens is a continuing threat to the poultry industry. Infection with Newcastle disease is greatly influenced by the immune status of the birds. The mucosal immunity plays a major role in the local immune response in the protection of chickens against diseases. This study was undertaken to find the efficacy of thermostable live oral pellet vaccine in developing the mucosal immunity in chickens. Samples were collected from Harderian gland, Lachrymal fluid, Tracheal fluid, Intestinal washings, Bile and Serum of chickens after administration of oral pellet vaccine to detect presence of NDV specific IgA antibodies. Results showed that there is significant increase in the immune response after one week post vaccination with no significant difference between 14 and 21 days after vaccine. There exists significant difference in Mean OD values between samples of Harderian, Lachrymal, Trachea, Intestine, Bile and serum with bile found to have increased IgA response. Challenge experiment results showed that oral pellet vaccine was able to protect chickens against virus challenge by increasing the mucosal immunity against Newcastle disease.