Diversity of haemoparasites in migratory small ruminants of Himalayas, India

Abstract

Vector-borne haemoparasitic diseases of migratory small ruminants have been less explored to date. Therefore, transhumant migratory sheep and goats of the Himalayas were molecularly screened for various vector-borne pathogens like Anaplasma, Theileria, Babesia, Anaplasma marginale, Theileria luwenshuni, Theileria orientalis, and Trypanosoma evansi using their specific primers. Out of the 171 animals screened, 73.09% of the animals were infected with Anaplasma spp. and 74.85% of the animals with Theileria spp., while no animals were found infected with Babesia spp. and Trypanosoma evansi. In a quest to identify the species, a few positive PCR amplicons representing Anaplasma spp., Theileria spp., and Theileria/Babesia spp. were sequenced. The sequences obtained were further BLAST analyzed to reveal maximum identity with Anaplasma capra (100%), Theileria luwenshuni (99.71%), and Theileria sinensis (98.73%). Among them Theileria luwenshuni was further confirmed with their species-specific PCR and the positive amplicons were sequenced and BLAST analysed to reveal their maximumsimilarity with Chinese isolates rather than Indian isolates. Further, phylogenetic analyses of the resulting sequences were conducted to identify their evolutionary history. It revealed that 1100 bp- amplicons of Theileria spp. were showing maximum likeness to Theileria sp. MK, a non-transforming Theileria. This is the first report of zoonotic Anaplasma capra and Theileria sp. MK in small ruminants from India and it could be mostly due to their transboundary migration history through the Indo-Tibetan border during summer seasons as a part of the traditional migratory system of livestock rearing practice in the Himalayas. The high prevalence of haemoparasites in migratory small ruminants calls for the adoption of effective control measures.