背景:近年来,我国浣熊犬毛滴虫病发生率较高。在以前的一些研究中,中国的浣熊犬中已经描述了人类五虫。揭示目的:浣熊犬是否可以被除人源外的其他滴虫物种感染,并阐明毛滴虫在浣熊犬中的患病率和种类分布。
方法:这里,这389份粪便样本是从河北省农场饲养的浣熊犬中采集的,所有样品均使用显微镜检查进行检测,并处理了一些含有滴虫样生物的粪便样品,培养,染色,并拍照。同时,通过基于人源小亚基rRNA(SSUrRNA)基因的物种特异性巢式PCR筛选所有样品,Tritrichomonas胎儿和四虫,分别,并对本研究中获得的所有阳性二次PCR扩增进行测序,对齐和分析。
结果:62份粪便样本(15.9%,62/389)在光学显微镜下为滴虫阳性,培养物中可见毛滴虫样细胞。PCR结果显示100例滴虫阳性,包括45份人源阳性样本(11.6%,45/389),32例胎儿阳性样本(8.2%,32/389),和33份T.buttreyi阳性样本(8.5%,33/389),分别。在10个样品中观察到双重混合感染。在腹泻的浣熊犬中,胎儿T.foetus和人源P.hominis的患病率均显着较高(13.9%,和25.0%)比无腹泻的浣熊犬(7.6%,和9.3%)(p<0.05)。在显微镜下确认为滴虫阳性的所有样品也通过PCR分析发现为滴虫阳性。测序和系统发育分析表明,本研究获得的序列属于人假单胞菌,T.胎儿和T.buttreyiSSUrRNA,分别。其中,本研究中获得的T.buttreyiSSUrRNA序列具有新的序列多态性。根据初步的形态学和分子分析,浣熊狗被认为是T.foetus和T.buttreyi的新宿主。
结论:这是关于中国浣熊犬中T.foteri和T.buttreyi的识别和流行的第一份报告,结果增加了我们对毛滴虫物种的寄主范围和患病率的了解。
BACKGROUND: In recent years, the trichomonosis in raccoon dogs in China had occurred frequently. Pentatrichomonas hominis had been described in raccoon dogs in China in some previous studies. PURPOSE TO REVEAL: whether raccoon dogs can be infected by other trichomonad species besides P. hominis, and clarify the prevalence and species distribution of trichomonad in raccoon dogs.
METHODS: Herein, the 389 fecal samples were collected from farm-raised raccoon dogs in Hebei Province, all the samples were detected using the microscopic examination and several fecal samples containing trichomonad-like organisms were processed, cultured, stained, and photographed. Meanwhile, all the samples were screened by the species-specific nested PCR based on the small subunit rRNA (SSU rRNA) gene of P. hominis,Tritrichomonas foetus and Tetratrichomonas buttreyi, respectively, and all positive secondary PCR amplications obtained in this study were sequenced, aligned and analysed.
RESULTS: 62 fecal samples (15.9%,62/389) were trichomonad-positive under light microscopy, and the trichomonad-like cells were clearly observed in the culture contents. The PCR results showed that 100 samples were trichomonad-positive, including 45 P. hominis-positive samples (11.6%,45/389), 32 T. foetus-positive samples (8.2%,32/389), and 33 T. buttreyi-positive samples (8.5%,33/389), respectively. Double mixed infections were observed in 10 samples. The prevalence of T. foetus and P. hominis were both significantly higher in raccoon dogs with diarrhea (13.9%, and 25.0%) than that in raccoon dogs without diarrhea (7.6%, and 9.3%) (p < 0.05).All samples confirmed as trichomonad-positive under microscopy were also found to be trichomonad-positive by PCR analysis. The sequencing and phylogenetic analysis demonstrated the sequences obtained in this study belonged to P. hominis, T. foetus and T. buttreyi SSU rRNA, respectively. Among them, the T. buttreyi SSU rRNA sequences obtained in this study harbored the new sequence polymorphisms. Based on preliminary morphological and molecular analyses, raccoon dogs are considered as the new host of T. foetus and T. buttreyi.
CONCLUSIONS: This is the first report about the identifcation and prevalence of T. foetus and T. buttreyi in raccoon dogs in China, and the results increase our knowledge about the host range and prevalence of trichomonad species.