Morphological Taxonomy Study On Trichodina Sp.Parasitic On Pelteobagrus Sp. In Sheyang Jiangsu Province And Toxicity Study On The Insecticide

Trichodiniasis is one of the main diseases of Pelteobagrus sp, which canhappen through the whole year, widely prevalent. It is the most harmfuldisease to fry and fingerling, which can lead to mass death. This studyinvestigated the epidemiology of Trichodiniasis of Pelteobagrus sp inSheyang yanchang from May2010to May2011, researched themorphological taxonomy of Trichodiniasis in Pelteobagrus sp gills;according to the situation of drug use in the epidemiology, we chose fourcommon drugs which can control Trichodinosis to conduct the acutetoxicity experiment on Pelteobagrus sp and Daphnia magna, so as toprovide the reference for the prevention and cure of the disease inPelteobagrus sp. This research mainly divided into the following threeparts:1. Epidemiology investigation of Trichodiniasis of Pelteobagrus sp inSheyang yanchangThis study investigated the epidemiology and drug prevention and controlof Trichodiniasis of Pelteobagrus sp in Sheyang yanchang from May2010to May2011. The results showed that this disease can occur throughout the year, with the incidence peak was from May to September,the water temperature from20℃to30℃, and infection rates ofPelteobagrus sp was as high as73.7%. Tracking survey found that thesudden changes of water temperature, changes of oxygen supply, rises ofnitrite would lead to the rise of the infection rates. Besides, this researchalso conducted a survey about drug use of prevention and control of theTrichodinosis, finding that the four kinds of drugs, including concludabamectin, mannichbasesingredient, Sophora extract and Melia extract,were very common for this disease.2. Morphological Taxonomy Study on Trichodina sp. parasitic on gills ofPelteobagrus sp in SheyangThe morphological characteristics of Trichodina modesta and Trichodinamastu parasitic on the gills of Peleteobagrus vachelli was detaileddescribed in the present study, including the shape, adhesive disc, denticle,radial pins, granules, nucleus and adoral ciliary spiral. In addition, themorphological comparison was also conducted with other populations ofT. modesta and T. mastu species previously reported. The study was thefirst report on the T. modest parasitic on P. vachelli.3. Safety evaluation of several control and prevention drugs ofTrichodiniasisIn order to validate the safety of four drugs collecting from theepidemiological survey, this study conducted the acute toxicity test， referring to the operation of the national standard, to Pelteobagrus sp andDaphnia magna for abamectin, mannichbasesingredient, sophoraflavescentis and Melia extract. The results showed that the sensibility ofPelteobagrus sp to the four drugs was different, sequencing of thesensitivity as follows: the abamectin> mannichbasesingredient> sophoraflavescentis> Melia extract. The ordering of four drugs toxicity toDaphnia magna is mannichbasesingredient>abamectin> sophoraflavescentis> Melia extract. The results confirmed thatmannichbasesingredient and abamectin were higher toxicity toPelteobagrus sp, not being suitable to prevent or control Trichodiniasisdisease of Pelteobagrus sp, while Sophora flavescentis and Melia extractwere suitable for the higher safe concentration.