Identification and genetic characterization of Blastocystis subtypes in Père David's deer (Elaphurus davidianus) from Shishou, China.

Blastocystis is a protozoan parasite frequently reported in the gastrointestinal tract of humans and animals, with a global distribution. No information on the infections of Blastocystis in Père David's deer (Elaphurus davidianus, PDD) is available. In this study, a total of 128 fecal samples collected in the National Nature Reserve of Shishou, Hubei Province of China, were used to determine the occurrence and subtypes of Blastocystis in PDD. Amplification of the SSU rDNA gene confirmed the common presence of Blastocystis infection, with an observed prevalence of 56.3% (72/128). Through nucleotide sequencing and phylogenetic analysis, five known subtypes, which consisted of one zoonotic subtype (ST10) and four ruminant-specifical subtypes (ST21, ST23, ST25, and ST26), were identified in this study. This represents a high degree genetic diversity of parasites within the host. Of the 72 PCR-positive samples, ruminant-specific subtypes were the most frequently observed, with ST21 being the most prevalent subtype (56.9.7%, 41/72). This is the first report characterizing the molecular subtypes of Blastocystis in PDD. The findings demonstrate a broad diversity and zoonotic potential of Blastocystis in PDD. Further study of the transmission potential between wildlife and humans or domestic animals in the region is required.