Dunn A M, Hatcher M J
Department of Biology, University of Leeds, UK.
Parasitology. 1997 Oct;115 ( Pt 4):381-5. doi: 10.1017/s0031182097001492.
This is an investigation of the impact of salinity on transovarial transmission and burden of a microsporidian sex ratio distorter in the inter-tidal crustacean Gammarus duebeni. Exposure of parasitized mothers to increased salinity during the gonotrophic cycle caused an increase in parasite burden in the follicle cells and a decrease in burden in the oocytes. It appears that salinity impedes parasite transmission from the follicle cells to the oocytes during host oogenesis. A lower proportion of the young were infected in broods from elevated salinity and, in infected offspring, parasite burden was lower than in control embryos. Parasite replication occurred during embryogenesis. However, the pattern of parasite growth did not differ between salinities, indicating that differences in parasite burden could be attributed to a reduction in the initial parasite burden transmitted to the gamete, rather than to a reduction in parasite replication during host embryogenesis. We discuss our findings with respect to parasite/host dynamics and the ecology of the host.
这是一项关于盐度对潮间带甲壳动物杜氏钩虾中一种微孢子虫性别比例畸变体的经卵传递及负荷影响的研究。在生殖周期中，将受寄生的母体暴露于盐度增加的环境下，会导致卵泡细胞中寄生虫负荷增加，而卵母细胞中的负荷减少。看来盐度在宿主卵子发生过程中阻碍了寄生虫从卵泡细胞向卵母细胞的传递。在盐度升高的亲代所产幼体中，受感染的比例较低，并且在受感染的后代中，寄生虫负荷低于对照胚胎。寄生虫在胚胎发育过程中进行复制。然而，不同盐度下寄生虫的生长模式并无差异，这表明寄生虫负荷的差异可归因于传递至配子的初始寄生虫负荷的减少，而非宿主胚胎发育过程中寄生虫复制的减少。我们结合寄生虫/宿主动态关系及宿主生态学对我们的研究结果进行了讨论。
