Analysis On Species Identification,Epidemic Characteristics Of Caryophyllidea On Fish In Irgis River,and Prevention Of Cestodiasis In Farmed Fish

Caryophyllidea, belonging to Platyhelminthes, Cestoda, It is a common parasitic of fish. In this article, with conventional fish parasitology survey methods and modern molecular biology techniques, we studied the species composition, epidemic characteristics of Caryophyllidea, fish parasites in Irgis River and analyzed the phylogeny of some species. And we analyzed control case of tapeworm in farmed fish. The main conclusions are as follows:(1) Carried out in accordance with the fish parasitology investigation method respectively autopsy collected parasites. The results of the survey show that Caryophyllidea found 5 species, respectively Caryophyllaeus laticeps, Caryophyllaeus sp., Khawia rossittensis, Khawia sinensis, Khawia sp., belonging to 2 families and 2 genera. 6 species of fishes was infected Caryophyllidea in Irgis River, respectively Abramis brama orientalis(Berg), Leuciscus idus(Linnaeus), Gobio gobio acutipinnatus(Men'schikov), Carassius auratus gibelio(Bloch), Stizostedion lucioperca(Linnaeus), Songpu mirror carp(Linnaeus).(2) We successfully identified Caryophyllaeus laticeps by molecular biology techniques; We analysed the population dynamics of Caryophyllaeus laticeps, the results of the survey show that One of Abramis brama orientalis had the highest rates of infection, 15.65%. And the infection intensity, 12.18. Abramis brama orientalis are particularly prone to infect, it was found that medium length were more likely to be infected with Caryophyllaeus laticeps.(3) Using morphology and molecular biology techniques, we found Carassius auratus gibelio infected by Khawia rossittensis and Gobio gobio acutipinnatus infected by Khawia sinensis. The morphological characteristics showed the larvae were preliminarily identified as Khawia specie. We identified Khawia rossittensis and Khawia sinensis by molecular biology techniques and their homology are 99% in GenBank. Through analyzing cox1 sequences genetic distance and phylogenetic tree, we found that Khawia rossittensis and Slovakia's are from the same specie, and the support rate is 98%. we found that sample B and Khawia sinensis are from the same specie, and the support rate is 95%. The results of molecular identification classification are consistent with the results of traditional morphological classification.(4) By the field investigation, we found some fish tapeworms in fish farms in Irgis River region. For example, Caryophyllaeus and Bothriocephalus. We provided the scientific methods of treatment, it is a good cure rate approximately at 85%. We provided the advice of prevention about Ligula, the infection did not occur in the next year.