Do algae blooms dilute the risk of trematode infections in threespine sticklebacks？  

作　　者：Alexandre BUDRIA Ulrika CANDOLIN 

机构地区：[1]Department of Biosciences, University of Helsinki, EO. Box 65, FI-00014 Helsinki, Finland

出　　处：《Current Zoology》2015年第6期991-995,共5页动物学报（英文版）

摘　　要：Human-induced growth of macro-algae is often assumed to increase trematode infections in fishes by increasing the abtmdanee and condition of the parasite＇s intermediate host - snails - as this can boost the release of trematode larvae, cercariae, from the intermediate hosts. However, macro-algae can also impose barriers to the transmission of cercariae and reduce infections. We investigated whether an increased growth of filamentous algae affects the transmission of Diplostomum pseudospathaceum cercariae to the threespine stickleback Gasterosteus aculeatus, a common fish in eutrophied shallow waters. We exposed stickle- backs to trematode cercariae in the absence and presence of artificial filamentous algae, and recorded effects on the proportion of sticklebacks infected and the number of encysted metacercariae per fish. No significant effect of artificial algae on cercariae transmission was detected. However, the body size and the sex of the sticklebacks were strongly correlated with the number of encysted metacercariae per infected fish, with females and larger individuals being more infected. We discuss different factors that could have caused the difference in parasite transmission, including sex-related differences in body size and behaviour of sticklebacks .

关 键 词：Anthropogenic disturbance CERCARIAE Dilution effect Diplostomum pseudospathaceum EUTROPHICATION Filament-ous algae Parasites Physical interference 

分 类 号：S858.265.9[农业科学—临床兽医学] TS251.7[农业科学—兽医学]