黄颡鱼肠道内寄生棘头虫位置分布的研究

长江丽棘虫和黄颡异１钩棘头虫单独在黄颡鱼肠中分布的相似性比例ＰＳ＝０．６８４。它们共同寄生在黄颡鱼肠道内，长江丽棘虫的寄生部位向前移，黄颡异钩棘头虫的寄生部位明显向后移，生态位宽度变窄，生态位重叠值下降。但是，它们的平均感染强度并未降低，种间正关联显著。

Studies on the Site Distributions of Acanthocephalan Worms in the Intestine of Pseudobaguas fulvidraco

Site distribution of two species of freshwater acanthocephalans Brentisentis yangtzensis and Arhythmacanthus pseudobagri, were studied in the intestine of Pseudobagua fulvidraco (Richardson).Each species when alone was capable of living in a large part of the intestine of P.fulvidraco, the distribution was similar, the percentage similarity, PS =0 684.Comparing joint infections with single species infection, the site distribution of two acanthocephalans appeared to exhibit site segregation,the distribution of B.yangtzensis moved forwards in the gut and A.pseudobagri moved backwords in the gut obviously.The niche width and niche overlap of two acanthocephalans were reduced significantly but the intensity of two helminths unchanged.There was a significant positive interspecific association between two acanthocephalans.