Molecular Identification and Survey of Trichomonad Species in Pigs in Shanxi Province, North China.

Simple Summary: Three trichomonad species (Tritrichomonas foetus, Tetratrichomonas buttreyi, and Pentatrichomonas hominis) may affect pig production. Moreover, P. hominis is a zoonotic species. In the current investigation, 362 fecal samples collected from pigs in three representative counties in Shanxi Province, North China, were molecularly tested for the three trichomonad species. The results showed that T. buttreyi was detected as the most common species, with a prevalence of 49.72%. Its prevalence was associated with region and age. Only one sample was tested positive for T. foetus, and this isolate showed minor allelic variations compared with those reported previously. For T. buttreyi, eight distinct sequence types were obtained, and only two displayed 100% nucleotide homology with the corresponding sequences reported previously. For the first time, we reported the prevalence and genetic characterization of T. foetus and T. buttreyi in pigs in Shanxi Province, North China, which provides baseline information for planning control strategies. Several trichomonad species have already been identified in pigs, and their pathogenic potential may not be ruled out. To date, however, no information is available regarding the prevalence of trichomonads in pigs in Shanxi Province, North China. In the present study, a total of 362 fecal samples collected from pigs in three representative counties (Qi, Jishan, and Shanyin) in this province were examined for Tetratrichomonas buttreyi, Tritrichomonas foetus, and Pentatrichomonas hominis using a nested polymerase chain reaction (PCR) with primers targeting the small subunit ribosomal RNA (SSU rRNA) gene. The overall prevalence of T. buttreyi was 49.72%, and region and age were found to be significantly associated with T. buttreyi infection, respectively. Only one pig fecal sample from Qi County was found to be positive for T. foetus, and all samples were negative for P. hominis. Molecular evolutionary analysis revealed that some T. buttreyi isolates showed complete genetic identity with those reported previously, and some T. buttreyi isolates and one T. foetus isolate showed minor allelic variations compared with those reported previously. This is the report of the molecular epidemiology of T. foetus and T. buttreyi in pigs in Shanxi Province, North China. These findings not only enrich the knowledge on the distribution of these trichomonad species in pigs in China but also provide baseline information for planning future research and control strategies. [ABSTRACT FROM AUTHOR]