Scanning electron microscopy of a novel indian nephropathogenic Infectious Bronchitis strain, ind/ ahl/16/01 in experimentally infected embryonated chicken eggs

Scanning electron microscopy of ---- ind/ ahl/16/01 in experimentally infected embryonated chicken eggs

Abstract

Avian infectious bronchitis (IB) is a common, highly contagious, acute, and economically important viral disease of chickens caused by avian infectious bronchitis virus (IBV) of Coronaviridae. Nephropathogenic strains have emerged from mutation of widely used classical, live attenuated IB vaccines which mainly protects from respiratory form of the disease. The present work is directed to study the ultrastructure of the new strain of IBV, the IND/AHL/16/01, that was first isolated from an outbreak of nephritis and gout related mortality cases of coloured layer pureline birds at Indian Council of Agricultural Research - Directorate of Poultry Research (ICAR-DPR). Molecular characterisation and phylogenetic analysis was carried out and it was confirmed that the isolate is a novel nephropathogenic strain. Nine-day-old Embryonated Chicken Eggs (ECE) obtained from in-house hatchery of ICAR-DPR were inoculated by allantoic route and observed for embryonic lesions and mortality. The allantoic Àuid from these ECE were collected into 2.5% glutaraldehyde and stored at 4 degree Celsius until processing. Scanning Electron Microscope (SEM) imaging by negative staining technique, revealed electron dense, pleomorphic Virus Like Particles (VLP's) of 120 nm diameter.