Prevalence of maternal antibody against infectious bursal disease virus in broiler chickens

Infectious bursal disease (IBD) is a highly contagious viral disease of young chickens. Both broiler and pullets; are highly vulnerable to the risk of this infection. The disease produces huge economic losses by producing direct and indirect effects. At present the control programme for IBD is based on creating sufficient immunity in breeding stock by giving live attenuated IBD vaccine as primer in the second week of age followed by vaccination with inactivated IBD vaccines as booster during 18 to 20 weeks of age. The antibody generated in this way in the parental stock is transferred to the progency chicks. The maternal antibody in the progency chicks presists upto 3 to 4 weeks and the chicks remain protected during the early high risk period. The level of antibody at a particular time plays important role in immune response to IBD vaccine. Further it has also been demonstrated that some amount of antibody has stimulatory effect on immune response to IBD vaccine. It is therefore, necessary that a study be conducted to determine the distribution of maternal antibody in the poultry population at various age levels and also in birds received from various sources. This study will help in determining the schedule of vaccination to control IBD in chicken. It is in this backdrop that this study has been planned.