Prevalence of avian infectious bronchitis virus in broiler chicken farms in south of Iraq, ۲۰۱۴ – ۲۰۱۵

Avian infectious bronchitis (IB), caused by a gammacoronavirus, is an OIE-listed (List B) disease and characterized by respiratory and renal involvements, causing high mortality, and economic loss in both layers and broilers. In comparison with other diagnostic methods, real-time polymerase chain reaction (RT-PCR) and conventional RT-PCR are potent, more sensitive and faster techniques for infectious bronchitis virus (IBV) detection. This research was conducted to detect IBV using specific primers of IB in three governorates (Basra, Thi-Qar and Muthana) in the south of Iraq. Tracheal specimens were collected from ۴۶ IB suspected commercial broiler flocks. XCE۲+ and XCE۲- Primers, which amplify all IBV serotypes, were used. Primers MCE۱+, BCE۱+ and DCE۱+ were used to amplify the specific nucleotide sequences of Massachusetts, ۷۹۳/B and D۲۷۴ genotypes, respectively. The results of real-time RT-PCR of this study showed that ۳۴ (۷۴.۰۰%) out of ۴۶ infected flocks were positive to IBV. The results of nested PCR showed that ۵۰.۰۰% and ۵.۸۹% of positive samples were belonged to genotypes ۷۹۳/B and Massachusetts, respectively, and the remaining positive (۴۴.۱۱%) were unknown. The results indicate presence of  Massachusetts and ۷۹۳/B IBV strains in commercial broilers in southern Iraq.

Keywords:

Avian infectious bronchitis , Broiler , Iraq , Real-time RT-PCR