Diversity of and novel species in collected from captive Eld's deer in Thailand.

insects are important ectoparasites of cervids and may affect humans that are incidentally bitten. The presence of zoonotic pathogen DNA, such as , and , raises the importance of insects in veterinary and human medicine. Eld's deer (), an endangered wild ruminant in Thailand, are bred and raised in the open zoo. The semi-wild zoo environment suggests ectoparasite infestation and potential risk for mechanical transmission of pathogens to visitors, zoo workers, or other animals. However, epidemiology knowledge of pathogens related to endangered wild ruminants in Thailand is limited. This study aims to determine the prevalence and diversity of and in the collected from captive Eld's deer in Chon Buri, Thailand. Of the 91 DNA samples obtained, 42 (46.15%) and 25 (27.47%) were positive for and by molecular detection, respectively. Further, 42 sequences of (4 nucleotide sequence types) showed 100% identity to those detected in other ruminants and blood-sucking ectoparasites. Twenty-five sequences of (8 nucleotide sequence types) showed 97.35-99.11% identity to the novel species from sika deer and keds in Japan. Phylogenetic trees revealed sequences were grouped with the clusters of and other ruminant-related , while sequences were clustered with the novel species lineages C, D, and E, which originated from Japan. Interestingly, a new independent lineage of novel species was found in obtained specimens. We report the first molecular detection of and on , which could represent infectious status of captive Eld's deer in the zoo. Wild animals act as reservoirs for many pathogens, thus preventive measures in surrounding areas should be considered to prevent pathogen infection among animals or potential zoonotic infection among humans.