Dept. of Vet. & A.H. Extension Education, Veterinary College and Research Institute, Ramayanpatti, Tirunelvlei-627 358 (Tamil Nadu)
1The Professor and Head, Department of Veterinary Medicine, MVC, Chennai
2The Professor and Head, Department of Veterinary Microbiology, MVC, Chennai
3The Professor and Head, University Publication Division TANUVAS, Chennai
The production of desi chickens in developing countries like India faces a major hurdle of infectious disease attacks-the most common being, Newcastle disease (ND). Desi chickens act as reservoirs of virulent ND virus (NDV) and must hence be considered as a continuing threat to poultry population throughout the world. As signs of clinical disease in chickens vary widely and diagnosis may be complicated further by the different responses to infection by different hosts, the identification of NDV outbreaks becomes difficult. Tirunelveli district of Tamil Nadu, India having high numbers of desi birds rearing was hence selected for the study. A randomly selected population of 10, 000 Desi birds, of an age group of 6–8 weeks, from various places of Tirunleveli district were identified for the vaccination and seroconversion studies. Blood samples were collected using filter paper technique from the selected desi birds on day-0 and 21 days post vaccination of oral pellet vaccine against Newcastle disease. Serological assay like haemagglutination inhibition test enabled the assessment of post-vaccinal antibody response. The serological value could be clearly related to the expected immune status of the vaccinated birds 21 days post-vaccination with HI titres of 24 or log24 or more against 4 HAU of antigen. The study concluded that antibody response among the birds vaccinated with oral pellet vaccine was found to be significant, with no incidence of respiratory stress and post vaccination mortality.
Desi birds, efficacy, Newcastle disease, oral pellet vaccine
