摘要
目的 测定血吸虫在自然环境中钉螺体内发育所需的有效积温。 方法 现场采集无血吸虫感染的钉螺 ,以钉螺∶毛蚴为 1∶2 0比例进行实验感染 ,感染后放回现场环境饲养 ,以逸蚴确定感染性钉螺 ,连续记录现场温度 ,根据变温动物发育有效积温的计算公式 (K =∑ (Tn-C)或K =N(T -C) ) ,计算血吸虫在钉螺体内发育成熟的有效积温 ,并与室内恒温条件实验进行对比分析。 结果 现场自然环境 (平均温度 2 5 .5 2℃ )尾蚴成熟逸出螺体的最低积温为 163 5 .70日度 ,最高积温为 2 813 .5 7日度 ,平均积温为 (175 2 .0 8± 176.0 0 )日度 ,平均有效积温为 (611.77± 82 .62 )日度 (95 %可信区间为 44 9.83～ 773 .71日度 ) ,显著低于室内恒温环境所需的有效积温 (t =11.76,P <0 .0 1)。 结论 自然环境规律性的昼夜温度变化对血吸虫在钉螺体内的生长发育有影响。
Objective To investigate the energy (or growing degree days) needed for development of cercaria of Schistosoma japonicum in Oncomelania snail raised in natural environment. Methods The uninfected snails were collected from the field, and exposed to the miracidia of S. japonicum by the ratio of 1∶20. After exposure, those snails were raised in natural environment and the natural temperature was recoded every day. The accumulated temperature and effective growing degree days of cercaria developing in snail were estimated by the formula of K=∑(T_ n -C) or K=N(T-C), and those data were compared with that of control groups that snail raised in cultural room in a constant temperature. Results At the condition of natural temperature with 25.52℃ of average temperature, the average accumulate temperature for cercaria mature was (1 752.08±176.00) degree days, ranging from 1 635.70 as lowest and 2 813.57 as highest. While the effectively growing degree days of cercaria developing in Oncomelania snail was (611.77±82.62) degree days (the 95% confidence ranging was from 449.83 to 773.71 degree days), which was significantly lower than that of control group. Conclusion The natural change pattern of temperature in day and night affected the development of cercaria developing in snail raised in natural environment.
出处
《中国寄生虫病防治杂志》
CSCD
2003年第5期260-262,共3页
Chinese Journal of Parasitic Disease Control
基金
国家自然科学基金项目 (No .30 0 0 70 684)~~
关键词
血吸虫
日本
钉螺
自然环境
恒温环境
有效积温
Schistosoma japonicum
Oncomelania snail
natural environmental
constant temperature
effectively growing degree days
