Research and control status of Pseudodactylogyrosis in cultured eel

Species of the monogenean genus Pseudodactylogyrus parasitizing anguillid eels are of global distribution, contributing to the familiar diseases in cultured eels such as Anguilla japonica, A. Anguilla, A. rostrata and A. australis. With plenty of Pseudodactylogyrus parasitizing and the large amount use of anthelmintic drugs, eels are susceptible to stress response and then suffer from other kinds of diseases, which has been causing great economic loss to the eel farming industry in China. The paper reviewed the Pseudodactylogyrus study of taxonomy, main species and infected hosts, epidemic trend in eel culture and main symptoms and pathological changes during infection, insecticidal effect of anthelmintic drugs, and current status of the prevention and control techniques of Pseudodactylogyrus infection. The effective prevention and control of Pseudodactylogyrosis was beset with difficulties, especially with the lack of specific preventive drugs, common secondary infection of induced oviposition afer drug use, the unclear mechanism of Pseudodactylogyrus specific selection for A. rostrata and A. anguilla and the formation of drug resistance after drug use, and immature in vitro culture technique of Pseudodactylogyrus. Therfore, the research of Pseudodactylogyrus in vitro culture technique, the establishment of artificial infection and passage system of Pseudodactylogyrus, development of safe control drugs with low toxicity, low residue and effective oral anthelmintic drugs for eels, and study on the ecological and immune prevention and control technology based on water temperature, pH, water velocity and biological natural enemies have to be settled urgently and provide strong technical support for the sustainable and healthy development of eel industry.