Comparison of clinico - pathological changes in SPF chickens infected with different Iranian genotypes of infectious bronchitis virus

Background and Aims: Infectious bronchitis (IB), caused by infectious bronchitis virus (IBV), is an acute and highly contagious disease in chickens. IBV is mainly considered a respiratory infection, other clinical manifestations, including renal, enteric and reproductive signs can be observed. Since there has been no study on evaluation of changes in biochemical parameters during IB infection, this study was designed to assess the serum biochemical factors in experimentally infected chicks with two IBV isolates. Materials and Methods: Two groups of 14-day-old SPF chickens were infected with two different isolates of IBV, Variant-2 like and IR-1 like genotypes respectively (35 chicks in each group). In addition, a group of 35 chickens remained non-infected as a control group. On days 1, 3, 5, 7, 14 and 21 and 28 post infection the sera of both infected groups and uninoculated control group was collected to measure the biochemical factors, including uric acid, creatinine, alanine amino transferase (ALT) and aspartate amino transferase (AST) using a standard auto analyzer. We used multiple comparison ANOVA followed by a posthoc test, (Level of significance <0.05). Results: There were no significant differences between evaluated parameters of each infected group in comparison with the control group. Conclusion: No changes were seen in serum factor levels between control and infected groups. In an experimental disease, there was no other infection to superimpose on IBV, so acute IBV infection was not strong enough to cause hepatic dysfunction or renal failure.