Infectious Diseases 2022

Infectious Diseases 2022

Infectious bronchitis: practical vaccination programme in laying hens

de Wit, J. J., et al. (2022) Avian Pathology. 51:1-13‏ 4 June, 2022

To achieve long-term protection of laying and breeding hens against aberrant egg production caused by infectious bronchitis virus (IBV), a vaccination programme incorporating both live-attenuated and inactivated IBV vaccines is required. High-quality IBV vaccines of both types are widely available, but the number of IBV variants of global importance continues to increase and it is not possible to develop vaccines against each one of them. Therefore, it is desirable to perform studies under controlled conditions to determine which IBV vaccine(s) provide the best protection for laying hens against different IBV challenges.
New reasearch by Prof de Wit et al. examined the efficacy, against challenge with five IBV strains of global importance, of an IBV vaccination programme including two live-attenuated IBV vaccines (Massachusetts and 793B types) and three different commercially available inactivated vaccines each containing antigen against at least one IBV strain. The results reported in the scientific journal Avian Pathology confirm the importance of IBV vaccination for laying hens, show that efficient live priming makes a beneficial contribution to this protection and confirm that inactivated IBV vaccines contribute significantly to effective protection against at least the five IBV challenge strains used here. Furthermore, the study support the “protectotype concept”, long-established using different live-attenuated IBV vaccines in young chickens, and the efficacy of different inactivated IBV vaccines in broadening protection against IBV challenges in laying birds.