牛中华泰勒虫(Theileria sinensis sp.nov.)新种 1.传统分类学研究

Theileria Sinensis sp nov:A New Species of Bovine Theileria --Classical Taxonomic Studies

对分离自我国甘肃中部地区土种黄牛体的泰勒虫未定种作了鉴定。与环形泰勒虫 (T .annulata)、瑟氏泰勒虫 (T .sergenti)、小泰勒虫 (T .parva)、突变泰勒虫 (T .mutans)、斑羚泰勒虫 (T .tautotragi)、附膜泰勒虫 (T .velifera)、水牛泰勒虫 (T .buffeli)作了形态学上的比较研究 ,观察到该未定种除了泰勒虫所共有形态外 ,还有其它泰勒虫所没有的且难以描述的特异形态 ,尤其在染虫率高峰期 ,特异形态占虫体总数的 2 0 %左右。该种还具有出芽增殖的特性 ,可在除脾牛体内大量繁殖 ,染虫率可达 5 2 6 9%的高峰 ,试验感染牛出现高烧、极度贫血、精神沉郁、食欲不振等临床症状 ,导致个别牛只死亡 ,剖检观察到某些脏器有严重病变 ,表明具有一定的致病力。媒介蜱尚不清楚 ,但已证实 ,在我国传播家畜泰勒虫和巴贝斯虫的 7种媒介蜱对该种无传播能力。传统分类学研究结果表明 ,该种不同于已知牛泰勒虫有效种 ,系一新种。由于这一新种首次在中国分离到 ,因而被命名为中华泰勒虫 (Theile riasinensissp .nov .) (梨形虫亚目 :泰勒虫科 )。

Identification of a species of Theileria isolated from cattle in central parts of Gansu Province was carried out.Morphological comparison with T.annulata,T.sergenti,T.parva,T.mutans,T.taurotragi,T.buffeli and T.velifera suggested that the species of Theileria not only have the shape shared by Theileria ,but also some strange shapes beyond word,especially when parasitemia was high,the rate of the strange shapes could be as high as 20%.The budding multiplication was also observed.The parasites could proliferate in splenectomized cattle and maximum parasitemia were as high as 52 69%,and the infected cattle showed serious anemia,high temperature,listlessness,lack of appetite,some of the cattle died of theileriosis.Lesions in some organs were observed in postmortem examination.The vector of T.sinensis was unknown,but experiments demonstrated that it could not be transmitted by 7 species hard ticks,which were the vectors of Babesia and Theileria distributed in China.Classical taxonomic studies suggested that the parasite is not the valid bovine Theileria sp and is considered to be a new species of Theileria .The parasites were named T.sinensis due to it was firstly isolated in China.