An Increase in the Number of Dead and Culled Chickens after Administration of Infectious Bursa! Disease Vaccine in Broiler Farm

Tsuneyuki Masuda, Yuko Tsuka, Ayako Okada, Natsuki Akashi, Chie Cho, Yosuke Sasaki, Terukazu Shimogishi, Hiroshi Yamasato

The number of dead and culled chickens increased in a broiler farm in Tottori prefecture in March 2015. The chickens displayed various clinical signs such as limb weakness and gizzard erosion. Atrophy of the bursa of Fabricius was commonly observed. More than 10,000 chickens died or were culled until shipping. The mild live infectious bursa! disease (IBD) vaccine had been used on the farm previously, but the IBD vaccine was changed to an intermediate type after the flocks were introduced. An adverse reaction to the intermediate vaccine was observed ; therefore, the IBD vaccination program was changed from the next flock introduction. As a result, the number of dead and culled chickens decreased compared with that in the earlier flocks. As reported previously, for IBD vaccination, it is important to consider the epidemic status of IBD in the community and on the farm.

J. Jpn. Soc. Poult Dis.,