Differentiation of infectious laryngotracheitis virus isolates by restriction fragment length polymorphic analysis of polymerase chain reaction products amplified from multiple genes

Abstract

Infectious laryngotracheitis (ILT) has been identified in most countries around the world and remains a threat to the intensive poultry industry. Outbreaks of mild to moderate forms of ILT are common in commercial layer flocks, while sporadic outbreaks of ILT in broiler flocks have also been recognized as an emerging problem in several countries. Examination of viral isolates using restriction fragment length polymorphism of polymerase chain reaction (PCR-RFLP) from individual ILTV genes has suggested that some of these outbreaks were caused by vaccine strains. In this study, PCR-RFLP of a number of ILTV genes/genomic regions including gE, gG, TK, ICP4, ICP18.5, and open reading frame (ORF) ..