Heidarpour Bami M, Haddadzadeh H R, Kazemi B, Khazraiinia P, Bandehpour M, Aktas M
Clinical Science Department, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Vet Parasitol. 2009 May 12;161(3-4):171-7. doi: 10.1016/j.vetpar.2009.01.035. Epub 2009 Feb 12.
Theileria spp. infect wild and domestic ruminants in the tropical and subtropical regions of the world. Two species, T. lestoquardi and T. ovis, are suspected to cause ovine theileriosis in Iran. The epidemiological aspects of ovine theileriosis in Iran are poorly understood, and further investigations by sensitive and precise techniques are required. In this study, the use of a nested PCR for amplification of a fragment of the 18S ribosomal DNA from virtually all species of Theileria is described. For differentiation of various Theileria spp. a RFLP assay was developed as a diagnostic tool enabling direct, concurrent, highly specific and sensitive identification of Theileria spp. The sensitivity of the nested PCR for Theileria species was 10(-5)% parasitemia. Restriction fragment length polymorphism (RFLP) of the PCR products allowed differentiation between three different Theileria species (T. annulata, T. lestoquardi and T. ovis) and seems to be useful for differentiation of other species such as T. separata and Theileria spp. china. From 100 field blood samples obtained from sheep in East and South-East Iran, 56% were positive for Theileria spp. by nested-PCR compared with 21% by microscopic examination. Out of 56 positive samples, 12.5% (7/56) were positive for T. ovis and 87/5% (49/56) were positive for T. lestoquardi. This is the first report in which T. ovis has been detected in Iran using molecular identification techniques.
泰勒虫属感染世界热带和亚热带地区的野生及家养反刍动物。在伊朗，两种泰勒虫，即小泰勒虫和绵羊泰勒虫，被怀疑会引发绵羊泰勒虫病。伊朗绵羊泰勒虫病的流行病学情况了解甚少，需要采用灵敏且精确的技术进行进一步调查。在本研究中，描述了使用巢式PCR扩增几乎所有泰勒虫属物种的18S核糖体DNA片段的方法。为区分各种泰勒虫属物种，开发了一种限制性片段长度多态性（RFLP）分析方法作为诊断工具，能够直接、同时、高度特异性且灵敏地鉴定泰勒虫属物种。巢式PCR对泰勒虫属物种的灵敏度为10^(-5)%的虫血症。PCR产物的限制性片段长度多态性（RFLP）可区分三种不同的泰勒虫物种（环形泰勒虫、小泰勒虫和绵羊泰勒虫），似乎也有助于区分其他物种，如中华泰勒虫和分离泰勒虫。从伊朗东部和东南部绵羊采集的100份野外血液样本中，通过巢式PCR检测，56%的样本泰勒虫属呈阳性，而显微镜检查的阳性率为21%。在56份阳性样本中，12.5%（7/56）的样本绵羊泰勒虫呈阳性，87.5%（49/56）的样本小泰勒虫呈阳性。这是首次在伊朗使用分子鉴定技术检测到绵羊泰勒虫的报告。
