Genotyping of avian Infectious bronchitis viruses in suspected broiler flocks in Ardebil, 2016

Infectious bronchitis virus (IBV) is the cause of acute respiratory viral disease in poultry with respiratory rats and coughing and sneezing. Corona viruses are created a wide range of respiratory, intestinal, liver and nervous disease with different virulence in cats, dogs, pigs, rodents, cows, birds and human. Corona viruses are able lots of recombination's and mutations. This ability gives them the opportunity to be active in different hosts and different climatic conditions, such as avian infectious bronchitis disease in poultry that can cause losses in broilers. S1 gene sequencing is used for molecular epidemiology and genotype characteristics of infectious bronchitis virus. For better understand the molecular epidemiology of infectious bronchitis virus in Iran, the IBVs gene isolates of broiler poultries from Ardebil province were sequenced in this study. A total of 30 tracheal swabs were collected from broilers in random in Ardebil province in 2016. For detection and genotyping of virus, RNA extraction was performed using RNA extraction kit. RT-PCR was used in one process for the production of cDNA, and then, RT-PCR product were amplified to identify infectious bronchitis virus using Nested-PCR with primers encoding 5’UTR, then, for genotyping of positive samples, gene sequencing of spike glycoprotein was performed 70% of tracheal swabs were positive and strain identification was done according to existing protocols. It can be concluded that the corona virus is spinning among broiler flocks in Iran. In this study, extraction and RT-PCR on suspected positive samples was repeated several times. During the test two negative controls was used including extraction negative control and RT-PCR negative control. Genetic analysis based on the highly variable nucleotide sequence of S1 gene showed that, the overall rate of infection was 70% and detected three genotypes in this area: Variant 2 (IS/1494), 793/B and MASS and QX overall percentages in respectively 52/3%, 33/5%, 9/5% and 4/7%.