Fundamental study for controlling a food environment against intestinal protozoa contaminated in tap water

隐孢子虫、环孢子虫和贾第鞭毛虫的宿主范围以及这些寄生虫侵入宿主细胞的过程尚不清楚。为了获得关于这些未解决问题的基本数据，我检查了家畜（包括牛和猪）的粪便，并发现寄生虫已被遗传识别。为了阐明隐孢子虫的侵入过程，本文对隐孢子虫侵入期的虫体进行了详细的分析。结果，在来自21个县的213个牛样本中，隐孢子虫呈阳性。检出毛细螺旋体13只（6.1%）、牛毛细螺旋体163只（76.5%）、牛毛细螺旋体15只（7.0%）、毛细螺旋体8只（3.8%）。所有隐孢子虫分离株经遗传鉴定为安德氏隐孢子虫，生物学鉴定为新种。在8个县的129份猪标本中检出艾美耳虫52头（40.3%），猪毛线虫32头（24.8%），夏季蛔虫19头（14.7%），尾圆线虫3头（2.3%）。我们的研究结果表明，环境抗性的卵或卵囊在日本农场广泛存在。在超微显微镜下，小孢子子的顶端可见3个顶环、1个电子密环和2个粗大的中心微管。免疫电镜观察到的这些细胞顶端骨架结构是由一个小管组成的。发现该孢子子的体外感染性在2hr内下降，表明在脱落后迅速侵入宿主细胞。

Host range as a reservoir about Cryptosporidium, Cyclospora, and Giardia, and invasive process of the Parasites into host cells remains unsolved. To obtain fundament data about these unresolved issues, I examined feces of domestic animals including cattle and pigs, and detected parasites were genetically identified. And to clarify the invasive process of Cryptosporidium, I analyzed the zoites of invasive stage in detail. As a result, of 213 cattle samples from 21 prefectures, Cryptosporicliunispp., Eilneria spp., Capillaria bovis, and Trichuris spp. infections were detected in 13 (6.1%), 163 (76.5%), 15 (7.0%), and 8 (3.8%), respectively. All the isolates of Cryptosporidium spp. were genetically identified as C.andersoni, and biologically identified as a novel type. Of 129 pig samples from 8 prefectures, Eimeria spp., Trichuris suis, Ascaris sumn, and Metastrongylus spp. infections were found in 52 pigs (40.3%), 32 (24.8%), 19 (14.7%), and 3 (2.3%), respectively. Our results indicate that environmentally resistant eggs or oocysts of the parasites are widespread on Japanese farms. By ultramicroscopy of C.parvum zoites, three apical rings, an electron-dense collar, and two thick central microtubules were seen at the apical end of sporozoites. C.parvum a tuhulin antigen was 50-kDa molecular weight by western blotting and these apical cytoskeletal structures observed by electron microscopy were composed of a tubul in by immunoelectron microscopy. It was found that infectivity in vitro of this sporozoite, declined within 2hr, suggesting that invasion into host cells after excystation was rapidly accompanied.