IDENTIFICATION OF LIFE CYCLE AND ESTABLISHMENT OF THE METHOD FOR DlAGNOSIS,PREVENTION AND TREATMENT OF NEOSPORA CANINUM

1.日本新孢子虫病发病率研究：迄今为止，该病在24个都道府县发生，在全国广泛分布。该病最早发生于1985年，从美国进口的牛中有大量的抗原虫抗体。舍饲犬和与牛饲养的犬经常有抗体。根据这些结果，我们怀疑原生动物在狗和牛之间循环，我们建议农民不要将狗与牛一起饲养。2.新孢子虫的分离：我们从日本流产的胎儿或先天性感染的新生小牛中分离到8株新孢子虫。3.传播方式的研究：在病牛附近的动物（狗、猫、小鼠、鸽子和浣熊）中均检测到抗原虫抗体，除狗外均无抗体。实验性感染这种原虫的裸鼠表现出神经根炎和消化道寄生虫的增殖。这些结果表明，新孢子虫可能通过感染动物的粪便垂直传播。

1.Study on the incidence of neo sporosis in Japan : the disease occurred in 24 prefectures so far and distributed widely throughout the country. The earliest occurrence of the disease was in 1985, and many cattle imported from USA had the antibody against the protozoa. Shelty dogs and dogs kept with cattle frequently had the antibody. Based on these results, a circulation of the protozoa among dogs and cattle was suspected and we recommended farmers not to keep dogs with cattle.2.Isolation of neospora : weisolated 8 strains of neospora from aborted fetuses or congenitally-infected newborn calves in Japan. Ribosomal DNA of our isolates was identical with those isolaed in USA.Antigen plates for fluorescent antibody test and latex beads ELISA kit were prepared using our isolales.3.Study on the mode of transmission : antibody against the protozoa was sought in various animals (dogs, cats, mice, pigeons and racoons) habitaing near the affected cattle, and none of them except dogs had the antibody. Nude mice experimentally infected with the protozoa showed radiculoneuritis and a proliferation of the parasites in the digestive tract. These findings suggested the a possible vertical transmission of neospora by the feces excreted from infected animals.