Susceptibility of chicks to infectious bursal disease (IBD) following vaccination of their parents with live IBD vaccine
Wyeth, P.J.; Cullen, G.A.
Veterinary Record 103(13): 281-282
1978
ISSN/ISBN: 0042-4900 PMID: 213872 Document Number: 129120
Vaccination of parent chickens with a commercial live infectious bursal disease (IBD) vaccine under field conditions at varying ages and by different routes resulted in variable susceptibility to the disease in their chicks. There was little correlation between the methods of vaccination and the levels of immunity in the chicks. There was some evidence that levels of transferred immunity decreased with the age of the parents. Of five flocks examined, the onset of susceptibility to IBD occurred at two days of age in two flocks and about one week of age in the other three. Four flocks were completely susceptible by the 27th day, the other at 31 days. Precipitins were demonstrated at day old in 100% of chicks in three flocks and in 80%. The precipitins had disappeared in all flocks by 17 days of age. The most effective way of applying live IBD vaccine to broiler chicks may be to give the vaccine just prior to an anticipated outbreak of disease having regard to the history of previous crops.