dos Santos Domingos Sávio, Andrade Michele Placedino, Varaschin Mary Suzan, Guimarães Antônio Marcos, Hirsch Christian
Instituto de Ensino Superior Presidente Tancredo de Almeida Neves.
Rev Bras Parasitol Vet. 2011 Oct-Dec;20(4):281-8. doi: 10.1590/s1984-29612011000400005.
Neosporosis is an important cause of abortion in cattle and information on their genetics and host parasite relationships are desirable. Neospora caninum samples obtained from 24 bovine fetuses from Minas Gerais, were genetically analyzed in part of the rDNA region, coding for rRNAs. Previously, brain, heart, liver, skeletal muscle, lung, kidney, spleen, thymus, lymph nodes, ovary or testis, uterus and skin of the ear were analyzed by conventional histopathology and immunohistochemistry. Of these, eight had lesions compatible in the brain and heart and two also in skeletal muscle and liver. Three brains showed antigen identification in immunohistochemistry. Brain and heart tissues were subjected to DNA extraction for PCR, whose product of 588 bp of ITS-1 region was sequenced in three samples. We obtained 96% similarity with dozens of sequences N. caninum deposited in GenBank. The phylogenetic tree showed great conservation among isolates of N. caninum in this study and those deposited in GenBank, while well-defined and specific branches were generated against other Apicomplexa. PCR for this region is useful as a diagnosis, with good analytical specificity, but the ITS-1 region is not suitable for genetic differentiation intra species because the sequences obtained were identical to the others analyzed.
新孢子虫病是牛流产的一个重要原因，因此需要了解其遗传学和宿主-寄生虫关系的相关信息。从米纳斯吉拉斯州的24头牛胎儿中获取了犬新孢子虫样本，对其核糖体DNA（rDNA）区域中编码核糖体RNA（rRNA）的部分进行了基因分析。此前，通过传统组织病理学和免疫组织化学方法对脑、心脏、肝脏、骨骼肌、肺、肾脏、脾脏、胸腺、淋巴结、卵巢或睾丸、子宫以及耳部皮肤进行了分析。其中，8个样本在脑和心脏中出现了符合病变的情况，2个样本在骨骼肌和肝脏中也出现了病变。3个脑样本在免疫组织化学中显示出抗原识别。对脑和心脏组织进行DNA提取以用于聚合酶链反应（PCR），在3个样本中对ITS-1区域588 bp的产物进行了测序。我们获得了与GenBank中数十条犬新孢子虫序列96%的相似性。系统发育树显示，本研究中的犬新孢子虫分离株与GenBank中保存的分离株之间具有高度保守性，而与其他顶复门寄生虫形成了明确且特定的分支。针对该区域的PCR作为一种诊断方法具有良好的分析特异性，但ITS-1区域不适用于种内遗传分化，因为所获得的序列与其他分析序列相同。
