| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1996: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1995: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Research Abstract |
Results obtsined in the present study are as follows ;
1. The infectivity of 4 species of Japanese Paragonimus (Paragonimus westermani, P.pulmonalis, P.miyazakii, P.ohirai) to 7 strains of rats (Inbred strain : F344/DuCrj, LEW/Crj, BN/Crj, WKY/NCrj ; Closed colony : Crj : SD,Crj : Wistar, Crj : Donryu) were surveyed. In general, BN/Crj rats showed high worm-recovery rate and tendency of high cyst fromation in the lungs though the remarkable differences were not recongnized among the rat strains. The results suggested that BN/Crj rats are available as substitutional animal of the definitive host such as cats and dogs for the establishment of experimental system of Paragonimus infection.
2. As for the infectivity of 2 or 3 species of Japanese Paragonimus (P.westermani, P.pulmonalis, P.ohirai) To the rats in experimental infections of immunosuppressed rats treated by predonizolone or congenital immunodeficiency rats (F344/NJcl-rnu), the results obtained were not different from those in the experimental infection used normal rats in the worm-development, worm-recovery rate and a tendency of cyst formation. Terefore it is supposed that cell-mediated immunity at least does not take part in paragonimus infection.
3. No worm were recovered from the house musk shrew Suncus murinus belonging to Insectivora in an experimental infection with P.westermani and P.pulmonalis. Hence it seems that Paragonimus is not so adapted for Insectivora as for Carnivora and/or Rodentia.
4. In an experimental infection of ferrets Mustera nigripes with 4 species of Paragonimus, no Paragonimus species except P.ohirai infect the animals. Hence, althougt there are one report in which the authors insist that ferrets serve as the experimental final host, further study will be needed about it.
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