Acknowledgments
This work was financially supported by the Gansu Province Guided Science and Technology Innovation Project [grant number GSCXZX-2019-2], Gansu Province Guided Science and Technology Innovation Project [grant number GSCXZX-2019-1], and Scientific Research Projects of Colleges and Universities of Provincial Education Department [grant number 2018C-15]. The authors thank Dr. Xingxu Zhao from College of Veterinary Medicine, Gansu Agricultural University, who has provided valuable guidance at every stage of writing of this manuscript.