丹江口水库三种鲤科鱼类寄生木村小棘吻虫的季节动态

作者于2004年2月至2005年2月调查了丹江口水库木村小棘吻虫Micracanthornhynchina motomurai(Harada,1935)感染三种小型经济鲤科鱼类--马口鱼(Opsariichthys uncirostris)、宽鳍(鱼鼠)(Zacco platypus)和油(粲鱼)(Hemiculter bleekeri bleekeri)的季节动态情况.在感染率和感染丰度方面,寄生于马口鱼和油(鱼鼠)的木村小棘吻虫呈现出显著的季节变化:秋冬季节感染率和感染丰度都比较高,而春夏季节比较低;与此不同的是,寄生于宽鳍(鱼鼠)中的木村小棘吻虫则全年都维持着较稳定的感染水平;木村小棘吻虫种群在三种宿主体内的总体感染丰度差异显著,但都呈聚集分布,三者的方均比与感染率和感染丰度之间无显著相关关系.

Seasonal dynamics of Micracanthornhynchina motomurai (Acanthocephala: Rhadinorhynchidae) in three cyprinids from the Danjiangkou reservoir

The seasonal dynamics of the acanthocephalan Micracanthornhynchina motomurai in the three small cyprinids,Opsariichthys uncirostris,Zacco platypus and Hemiculter bleekeri bleekeri in the Danjiangkou reservoir was investigated from February 2004 to February 2005. The prevalence and abundance of the acanthocephalan exhibited very similar and significantly seasonal change patterns in O.uncirostris and H.bleekeri bleekeri.The infection levels were higher in autumn and winter,but lower in spring and summer.However,the infection levels in Z.platypus kept stable all the year round.There were significant differences among the overall abundance of the acanthocephalan in the three host populations.Nevertheless,the frequency distribution of the parasite in the three kinds of fish was over-dispersed in most seasons and in total as measured by the variance to mean ratio.The variance to mean ratio was not found related to the infection levels.