ABSTRACT:
Avian Influenza (AI) disease is an infectious and highly contagious viral disease infected poultry and cause respiratory, digestive distress and sudden death combined with high mortality may arrived to (90%) in infected field. In the last years, poultry industry in Iraq suffered from high mortality arrived to (20-90%) in some farms or more than with severe respiratory distress and sudden death. In addition, grossly characterized by tracheitis, lung congestion, hemorrhagic Payer?s patches and cecal tonsils that led to high economic losses in poultry industry. This study was designed to isolate and identificate the causative agent by using HA-HI test and RT-PCR assays. A total of 20 samples (lung, trachea, spleen and intestine) were collected from organized farms from Karbala city suspected with AIV infection. All samples were inoculated into the allantoic cavity at (9-11) days old embryonated eggs with cultivation for six days. After that, the allantoic fluid was collected and stored in deep freeze. The HA-HI test was conducted to identify AI virus by using specific antisera. Results revealed that six samples were infected with AIV with HA-HI test and all samples were confirmed by using molecular methods (RT-PCR) test. Nucleotide sequences of H9N2 subtypes of AIV was obtained from NCBI websites and alignment with other researchers concerned in this topic. In conclusion: our results were obtained that all six farms infected with H9N2 subtypes.