Attenuation of infectious bursal disease virus and vaccination trials under laboratory and field conditions

Abstract

Adaptation to the chicken embryo of a vims strain of infectious bursal disease resulted in a reduction in virulence. After 60 passages the strain was attenuated enough to be used as a vaccine. The attenuation proved adequately stable. If given orally in the drinking water, the strain induced the development of neutralising and precipiting antibodies and a strong resitence against the disease. Promising results have also been obtained in the field. © 1974, American Industrial Hygiene Association. All rights reserved.