Molecular detection and genotyping of Anaplasma spp. and Theileria spp. infections in sheep and cattle from the northeast region of China

Trop Biomed. 2017 Dec 1;34(4):991-999.

Abstract

Anaplasmosis and theileriosis are significant tick-borne diseases threatening the livestock industry worldwide. In the present study, we screened 127 cattle and 115 sheep blood DNA samples from northeastern China for Theileria and Anaplasma pathogens by polymerase chain reaction (PCR) using species-specific primers. The result showed that only Theileria orientalis and Anaplasma ovis were detected, with a prevalence of 2.9% for T. orientalis in cattle and 57.4% for A. ovis in sheep. Fragments of Anaplasma ovis major surface protein 4 (AoMSP4) and Theileria orientalis major piroplasm surface protein (ToMPSP) genes were sequenced for phylogenetic analysis. Sequence analysis showed that the AoMSP4 gene was conserved, with 100% sequence identity value among sheep samples. However, the ToMPSP gene was relatively diverse, with sequence identity ranging from 87.6%-99l.0% among cattle samples. Phylogenetic analysis showed that the ToMPSP gene sequences isolated from 4 cattle samples were classified into type 1, type 2 and type 7, while the AoMSP4 gene sequences obtained from 66 sheep were classified into genotype I, according to the neighbour-joining distance method. This study provides important data for understanding the epidemiology of tick-borne diseases and genetic diversity of these pathogens in the northeast region of China.