First report of genetic diversity and risk factor analysis of equine piroplasm infection in equids in Jilin, China.

BACKGROUND

Equine piroplasmosis (EP) is a tick-borne hemoprotozoan disease of equids, caused by Theileria equi and Babesia caballi. Equine piroplasmosis represents a serious challenge to the equine industry due to important economic losses worldwide. The present study aimed to evaluate the prevalence of Theileria equi and Babesia caballi infections in equids from Jilin Province, China.

METHODS

A total of 220 blood samples (192 horses and 28 donkeys/mules) were collected from March 2018 to October 2019 in five districts of Jilin Province and analyzed by PCR. Potential risk factors, including the region, sex, management, and host species of the animals were assessed in relation to T. equi infection. Moreover, the V4 hypervariable region of the T. equi 18S rRNA gene was analyzed to identify specific genotypes.

RESULTS

The overall prevalence of T. equi in equids was 27.7%, whereas B. caballi infection was not identified. The district with the highest positive rate was Baicheng (43.3%), followed by Tonghua (28.9%), Yanbian (26.4%), Jilin (23.3%), and Liaoyuan (20.9%). The sex of the animals and farm management were identified as main risk factors, which were significantly associated with the prevalence of Equine piroplasmosis (P < 0.05). The risk factor analysis indicated that the females were at a higher risk (OR: 2.48, 95% CI: 1.17-5.27) of being infected compared to the males, whereas the organized farm was protective factor (OR: 0.42, 95% CI: 0.22-0.80). The phylogenetic analyses revealed that there were two T. equi genotypes (A and E) in Jilin.

CONCLUSIONS

Our findings provided important epidemiological data for the prevention and control of T. equi infection in Jilin, China.