Molecular identification of Linognathus spp. lice infesting sheep and goats in Mosul city, Iraq

Lice infestation is prevalent worldwide and it is one of the most significant veterinary parasitic diseases.  This study was applied from August to December, 2022, a total of 25 sheep lice and 25 goat lice were collected. The study based on microscopic and molecular identification by traditional polymerase chain reaction (PCR) technique and sequencing to confirm the Linognathus species infesting sheep and goats reared together. Microscopically, the morphological results identified the species infesting sheep and goats were sucking lice belonging to the genus Linognathus spp. The morphological characteristics of the adult lice were somehow identical for the same genus and was difficult to identify species, thus using  polymerase chain reaction (PCR) and gene sequencing on five samples of sheep and goats, the results confirmed that the species are belonging to Linognathus africanus by amplification of mitochondrial cytochrome c oxidase subunit I (COI) gene with reaction product of 379 bp that were isolated from the city of Mosul, with the accession numbers 598894PP, PP598895, PP598896, PP598897 and PP598898, genetic tree results revealed similarities with results of other countries recorded in the Global Genbank, 100% with Hungary, 99.44% Mexico, China and the United Kingdom while 99.17% in Mexico, but had a significant distance other strains for different species recorded in the United Kingdom, China, Canada and Australia with percentages 77.81%, 77.78%, 77.5% and 76.94 respectively.