سید الیاس طبا طبایی زاده - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
رضا طرقی - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
ناصر مرگان ازغدی - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
حمیدرضا فرزین - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
شهرام شرقی - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
مزگان سارانی - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
مجید جمشیدیان مجاور - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
جواد اعلمی ابرده - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
محمود قربان زاده - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
مریم ترابی - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
علیرضا صدر بزار - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
مجتبی فخرایی - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
نفیسه کیوانی راد - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
الناز وجودی - Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran
مجید خداوردی ازغدی - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran
تبسم مردانی - Veterinary Head Office of Khorasan Razavi, Mashhad, Iran

Infectious bronchitis (IB), caused by infectious bronchitis virus (IBV), is one of the most important respiratory diseases in poultry. The implementation of preventive measures, including vaccination and biosecurity, is necessary for controlling the disease. To maintain biosecurity, it is important to identify the entry route of new viruses into a region and characterizing markers such as unique mutations that make viruses traceable. During a genotyping study for IBV infected commercial chicken flocks in Khorasan Razavi province, ۱۱ viruses from ۱۱ broiler and layer chicken flocks were detected in different cities by PCR. Sequencing of the S۱ partial gene followed by phylogenetic analysis showed that eight viruses can be classified in GI-۲۳ lineage (Is-Variant۲), two viruses are classified in GI-۱ lineage (Mass), and one virus is classified in GI-۱۲ lineage (۷۹۳B). Although detected viruses of GI-۲۳ lineage are originated from Iran, seven viruses have synonymous (T۹۵۴C and G۱۰۵۶A) and non-synonymous (C۷۹۷T) mutations that have not been previously reported. It was found that the new genetic changes in Iranian IBVs of GI-۲۳ lineage occurred in two different regions in Khorasan Razavi. In conclusion, this study indicates that the high prevalence of GI-۲۳ lineage viruses in Iran may enhance the chance of virus mutations and the emergence of new viral strains, so effective vaccination and biosecurity measures are required to control the virus spread.

IBV, Genotyping, GI-۲۳ lineage, Mutation, Iran