摘要
本研究应用从螺卵孵化的湖北钉螺湖北亚种（Ｏｎｃｏｍｅｌａｎｉａｈｕｐｅｎｓｉｓｈｕｐｅｎｓｉｓ）经同时确定其性别及螺龄后，于同等条件下比较了不同性别及月龄的钉螺对中国安徽日本血吸虫的易感性。观察的内容包括：钉螺感染率、死亡率、尾蚴逸出前期及逸出尾蚴数量等。５－６月龄及１２－１３月龄的雌、雄两性成熟钉螺对日本血吸虫的易感性无显著差别，且其尾蚴逸出前期的平均天数亦无差别。３－４月龄的雌螺较雄螺更为易感，且雌螺的尾蚴逸出前期平均天数亦较雄螺的长４．７ｄ。１２－１３月龄雌、雄两性的老龄螺均较３－４月龄雌、雄两性的幼龄螺更为易感，但雌、雄两性幼龄螺被日本血吸虫感染后的死亡率均较老龄螺的为高，且幼龄螺的尾蚴逸出前期平均天数均明显地较老龄蚴的分别长９．４和６．５ｄ。虽然老龄和幼龄的雌、雄两性阳性螺在观察６０ｄ内逸出尾蚴的均数无差别，但幼龄雌、雄螺的逸蛐高峰时间则分别较老龄雌、雄螺推迟１０或２０ｄ。最后，对过去文献中有关日本血吸虫人工感染不同性别及螺龄的湖北钉螺所呈现相互矛盾的结果进行了分析和讨论。
The laboratory bred Oncomelania hupensis hupensis snails cultivated from eggs were used in the study. Consequently the age of the test snails at the time of exposure was known and the sex of snails at different ages were identified under the teroscope. All snails were exposed individually to 20 miracidia of Chinese mainland strain of Schistosomajaponicum originated from Anhui province. The infection rate, mortality, precercarial period and cercarial production of test snails were observed and compared.No significant difference in the infection rate was observed between the male and female snails at both 5-6 months and 12-13 months old of age(Tables 1-2), and also no significant difference in the mean days of precercarial period between male and female snails of these two age groups. It appears that once infection is established in adult Oncomelania snails, sporocyst-cercarial development proceeds normally in males and females. However, in the case of young snails at 3-4 months-old, infection rate in female snails(27.2%) was higher than in males(17.4%), and the mean days of precercarial period in females(87.9±9.9) were longer than in males(83.2±8.1), showing statistically significant difference. As to the results on comparison of males and females between young snails(3-4 months-old) and old ones(12-13 months-old), the infection rates in both males (30.6%) and females (38.4%) of old snails were significantly higher than in males(17.4%) and females(27.2%) of young snails. However, the mortalities in males (25.8%) and females(22.6%) of young snails followiing S. japonicum infection were markedly higher than those in males(16.0%) and females(14.0%) of old ones, and the mean days of precercarial period in both males and females of young snails were 6.5 to 9.4 days longer than those in old snails respectively. There was no obvious relationship in the average number of shedded cercaria from the initial 60 days in sexes or ages of snails infected with S-j aponicum. However, the times which the infected young snails reach the cercaria-shedding peak in males and females were 10 or 20 davs later than those in old snails respectivelv.
出处
《寄生虫与医学昆虫学报》
CAS
1994年第4期21-26,共6页
Acta Parasitologica et Medica Entomologica Sinica
关键词
日本血吸虫
钉螺
易感性
宿主
寄生虫
Schistosomajaponicum
Oncomelania hupensis hupensis
Susceptibility Host-parasite relationships
