Phylogenetic analysis of Jaagsiekte sheep retrovirus (JSRV) in Iraqi Awassi sheep

Jaagsiekte sheep retrovirus (JSRV) infection in sheep results in contagious ovine pulmonary adenocarcinoma (OPA). The aim of this study was to detect the presence of JSRV in Iraqi Awassi sheep of Al-Qadisiyah Province using reverse transcription-PCR (RT-PCR). Lung secretion samples from 50 adult sheep (1.5 to 2-year-old) during 2016-2018 that were suffering from chronic respiratory distress with suspected clinical OPA were collected. RT-PCR assay for detection of JSRV was conducted using primers specific for its 382 bp envelope protein gene. The results showed that 22 of the 50 (44%) lung secretion samples were positive for JSRV. Phylogenetic tree analysis revealed the JSRV sequence detected in the local Iraqi sheep population was closely related to NCBI BLAST locus isolates KT279066.1 and KT279065.1. The study found that the JSRV disease is prevalent in the Iraqi Awassi sheep flocks and that the local JSRV isolate is genetically divergent from most other global isolates.