Studies On Parasitic Fauna Of Portion Fish Nematode And Molecular Systematics Of Contracaecum Sp. In The Ergis River

By the Traditional fish parasitology research methods and modern molecular biologytechniques, study on the parasitic nematode species composition, seasonal dynamics andpopulation ecology, phylogeny of Contracaecum sp.,which parasites in Carassius auratusgibelio from Apr.2009to Jan.2010in Ergis River.The main conclusions are as follows.(1) This experiment were necropsied21kinds of fish,1776Fish,including7kinds ofexperimental fish infected with parasitic nematodes, accounting for experimental fish33.3%.There were5species of nematode which were collected from the Ergis River,Theybelong to3families,3orders,4classes.Including:Capillaria sp、Raphidaacaris larvae sp.、Camallanus Lacustris、Camallanus cotti、Contracaecum sp..The where Camallanus Lacustrisis newly recorded species, in china,t Contracaecum sp infected host was most widely.(2) From the results of these,Parasites in the body of Carassius auratus gibelioContracaecum sp infection in both seasons, spring and winter infection, intensity of infectionand infection abundance were higher, and decreased in summer,a slight increase in autumn,achieve maximum in winter. Analysis of spatial distribution of parasite populationsContracaecum sp. Was aggregated distribution in the host body.(3) Identify the species by the methods of morphology and molecular biology, andmensurate the ITS-2rDNA sequence of Contracaecum sp.,and compare with the sameclasses from GenBank.By comparison with GenBank Contracaecum sp. results show that thehomology of97%(425/439), the the base deletion rate of2%(9/439) to determine theheart.That derived from the NJ phylogenetic tree can be seen Contracaecum rudolphiiContracaecum variegatum, Contracaecum ogmorhini, Contracaecum eudyptulae,Contracaecum chubutensis and Contracaecum bioccai poly with a high rate of support.