Variability in biological behaviour, pathogenicity, protectotype and induction of virus neutralizing antibodies by different vaccination programs to infectious bronchitis virus genotype Q1 strains from Chile.

Variability in biological behaviour, pathogenicity, protectotype and induction of virus neutralizing antibodies by different vaccination programs to infectious bronchitis virus genotype Q1 strains from Chile. Avian Pathol. 2017 Jun 29;:1-24 Authors: de Wit JJ, Dijkman R, Guerrero P, Calvo J, Gonzalez A, Hidalgo H Abstract In the period from July 2008 to 2010 a disease episode resulting in serious economic losses in the major production area of the Chilean poultry industry were reported. These losses were associated with respiratory problems, increase of condemnations, drops in egg production and nephritis in breeders, laying hens and broilers due to infections with infectious bronchitis virus (IBV). Twenty-five IBV isolates were genotyped and 4 strains were selected for further testing by pathotyping and protectotyping. Twenty-four IBV isolates were of the Q1 genotype. The experiments also included comparing the ability of 6 vaccination programs to induce virus neutralizing antibodies (VNA) in layers against 4 selected Chilean strains. Despite the high genetic homology in the S1 gene between the 4 strains, the heterogeneity in biological behaviour of these different Q1 strains was substantial. These differences were seen in embryonated eggs, in cell culture, in pathogenicity and level of cross-protection by IBV Massachusetts (Mass) vaccination. This variability underlines the importance of testing more than 1 strain per serotype or g...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research