@Article{, title={EFFICACY OF INFECTIOUS BRONCHITIS DISEASE VACCINES AS MEASURED BY VIRAL SHED AFTER VIRULENT CHALLENGE IN BROILER}, author={Sahar Hamdi Abdulmaged}, journal={Basrah Journal of Veterinary Research مجلة البصرة للابحاث البيطرية}, volume={16}, number={2}, pages={248-258}, year={2017}, abstract={Infectious bronchitis threatens the poultry industry throughout the world, Thecontrol of IB of the big problems in the world because of the wide variations inserotypes and development in the virulence of strains from time to time, and nature isvery contagious, the rapid evolution in the specific tissue tropism and recombinantsbecause of the synchronization of infection with different virus types and the use oflive vaccines.found that the IB virus which is isolated from the recent outbreak is thesame serotype but the difference genotype compared with the strains of currentvaccine. Previous studies have indicated that the broiler vaccination with inactivatedvaccines showed significantly less virus shed if challenge with the homologousvaccines (same genotype viruses) as compared with birds that vaccination geneticallyheterologous vaccines. The current study compared the extent of protection resultingfrom vaccination with live Commercial vaccines(Volvac® IB Mass MLV, Poulvac®IB Primer (D274), Avipro® IB M48 and mixed vaccine from (Volvac®, Poulvac® andAvipro®)). Vaccinates werechallenged with virulent field isolate (Variant2) strain.Weekly post-vaccination, collected serum for analytical knowledge of the amount ofantibodies using hemagglutiation inhibition test against all vaccine antigens used inthe experiment after challenge with field virulent (Variant2 isolate), examine the birdsdaily to monitor the morbidity and mortality rates in selected periods for sheddingvirus by real time PCRto detect and quantitate the IBV viral copy number fromclinical samples.After challenge with (Variant2) birdsvaccinated with mixed vaccinerevealed less shedding virus compared to (Volvac®, Poulvac® and Avipro®)-vaccinated birdsboth separately.Genotypic differences between the vaccines and thechallenge virus do not reduce the ability of vaccines to protect against the disease, butgenotypic similarities reduce the virus shed and limiting its spread. The use of same249genetically advanced vaccines and expected to provide the best protection against thechallenge with virulent field IB strains and limit the spread of poultry farming

} }