Molecular survey and characterization of tick-borne pathogens in sheep from Qinghai, China

In this study, 277 sheep blood samples were collected from 7 counties in Qinghai and tested by PCR to detect and identify the above mentioned tick-borne pathogens. Among the 277 sheep, 176 (63.5%) were infected with at least one pathogen. A. ovis was the most prevalent pathogen (n = 112, 40.4%), followed by T. luwenshuni (n = 108, 39.0%), T. uilenbergi (n = 65, 23.5%) and B. motasi sp. L/N/T (n = 11, 4.0%). Interestingly and importantly, 83 (30.0%) infections with two or more pathogens were identified. The results of sequence analysis indicated that A. ovis msp4, B. motasi sp. L/N/T rap-1b, T. luwenshuni 18S rRNA and T. uilenbergi 18S rRNA gene sequences from Qinghai were variable. The identities to previously published Chinese isolates were 97.7-99.7%, 87.0-99.8%, 98.2-100% and 91.3-100%, respectively. The phylogenetic analysis revealed that all A. ovis msp4 sequences belonged to the same clade. On the other hand, B. motasi sp. L/N/T rap-1b isolates showed a closer relationship with B. motasi sp. BQ1/Lintan. One T. luwenshuni and one T. uilenbergi sequence from this study formed branches divergent from the other isolates. Overall, these results provide a better understanding of the prevalence and molecular characterization of TBPs in sheep in Qinghai and suggest that these pathogens require more attention from veterinarians.
Source: Small Ruminant Research - Category: Zoology Source Type: research