Biological characterization and molecular detection of field isolates of infectious bronchitis virus

Two field isolates of IEV were recovered from bird with different clinical manifestations viz. India/LKW/56/IVRI/08 from birds with respiratory disease complex and India/NMK/72/IVRI/10 from birds with nephritis. These isolates were adapted in 9–11 day-old embryonated chicken eggs (ECE). Typical lesions in embryos were curling and dwarfing with compressed feet over the head and embryos curled into a spherical form covered by thickened amnion and allantois; Increase in the volume of allantoic fluid and urates deposition in the mesonephrons were observed in infected embryos. At 12th passage level, the allantoic fluid of isolate India/LKW/56/IVRI/08 was having titre as 5X10^5.48 EID₅₀/ml. The presence of IEV in infected allantoic fliud harvested at 3^nd passage were confirmed by N gene diagnostic PCR and also by nested PCR of 3 UTR region. This study further confirms that circulation of different types of IEV in Indian poultry.