Control of infectious bursal disease with reference to vitamin E supplementation

The study was conducted to find out an effective field oriented vaccination schedule, and to study the additional benefit of vitamin E supplementation. A total number of 250-day old commercial broilers were used for this study. The pre vaccination blood samples were collected on day one from 10 chicks taken at random from the flock of 250 chicks to determine maternal antibodies. On day 10, 200 chicks were divided into four groups designated as A, B, C and D. Chicks in group A and C were vaccinated for IBD on day 10 and the remaining on day, 12. Two experimental groups (C & D) were fed with supplementary vitamin E, (178 mg/kg diet) after priming dose of vaccination till' the end of experiment, while the remaining two groups (A & B) were fed the same diet without vitamin E supplementation. Post vaccination blood samples from 10 chicks, randomly selected from each group, were collected on day 20 in case of group A and C, 22 in case of group B and D which was repeated on day 32 in case of group A and C, and day 34 in case of group B and D. The IHA antibody titre determined in response to priming dose for group A and B was found to have a GMT value of 73.48 and 63.97, respectively and in response to boosting dose the GMT values were 84.41 and 51.96, respectively the GMT values of group C and D in response to priming dose of vaccination was 127.93 and 146.96, respectively and in response to boosting dose the GMT values were 137.11 and 127.93, respectively. The IHA test results indicated that schedule I was more elective as compared to schedule 2. The higher GMT value in group C and D as compared to group A and B showed the positive effect of dietary vitamin E supplementation by inducing higher immunity. Vitamin E supplementation in the diet at the given rate was effective for the enhancement of immune status of broilers. Vaccination schedule 1, adopted in present study, providing priming dose on day 10 and boosting dose an day 22 gave better response in terms of GMT value.