福州地区家鸭次睾吸虫流行病学的调查研究

调查了5366只家鸭,次睾吸虫总感染率为19.6%,其中,东方次睾吸虫(Metorchisorientalis Tansbe,1921)感染率为9.3%,台湾次睾吸虫(M.taiwanensis Morishta etTseuchimochi,1929)为11.7%,混合感染率为1.4%.这两种吸虫的最高感染月份分别为9月(21%)和8月(32%).东方次睾吸虫感染度低于台湾次睾吸虫(P<0.01).从螺类调查和人工感染试验确证次睾吸虫的第一中间宿主是纹沼螺(Parafossarulus stritulus(Benson)).次睾吸虫尾蚴主要在白天逸出,呈明显的日周期变化,水温与光照是影响逸出的主要因子.实验条件下,东方次睾吸虫完成一个生活史至少需128d,其中螺内88d,鱼体30d,鸭体15d.

Studies on Epidemiology of Metorchis orientalis and M. taiwanensis of Ducks in Fuzhou, Fujian

5366 gall bladders of ducks were examined. It was found that 19.6% of these ducks were infected by Metorchis, in which M. orientalis acounted for 9.3%, M. taiwanensis 12.0% and two species mixed 1.4%. The infection peak of M. orientalis and M. taiwanensis was respectively in the months of August (32.0%) and September (21.0%) during a year. Only the freshwater snail, Parafossarulus striatulus (Benson), was proved to be the first intermediate host for both species by field research and experimental infection. The cercariae of M. orientalis emerged regularly from positive snail in the daytime. The main factors affected on emerging of the cercariae are temperature and light. Under experimental condition, it would take at least 128 days to complete a life cycle of M. orientalis; They parasite in snail for 88 days, in cyprind fish, such as Pseudorasbora parva for 30 days and in duck for 15 days.