Iranian Journal of Fisheries Sciences

en Experimentally pathogenesis of Aeromonas hydrophila in freshwater Crayfish (Astacus leptodactylus) in iran fish disease fish disease پژوهشي Orginal research papers In this research the affect of A. hydrophila on pathogenesis of Crayfish A. leptodactylus was carried out. This study was designed in three groups as treatments and one group as control in triplicate with 20 Crayfish in each glass aquarium. The treatments have exposed to A. hydrophila. The concentrations of the bacteria in treatments were <v:shapetype id="_x0000_t75" stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" o:preferrelative="t" o:spt="75" coordsize="21600,21600"> <v:stroke joinstyle="miter"> <v:formulas> <v:f eqn="if lineDrawn pixelLineWidth 0"> <v:f eqn="sum @0 1 0"> <v:f eqn="sum 0 0 @1"> <v:f eqn="prod @2 1 2"> <v:f eqn="prod @3 21600 pixelWidth"> <v:f eqn="prod @3 21600 pixelHeight"> <v:f eqn="sum @0 0 1"> <v:f eqn="prod @6 1 2"> <v:f eqn="prod @7 21600 pixelWidth"> <v:f eqn="sum @8 21600 0"> <v:f eqn="prod @7 21600 pixelHeight"> <v:f eqn="sum @10 21600 0"> </v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:f></v:formulas> <v:path o:connecttype="rect" gradientshapeok="t" o:extrusionok="f"> <o:lock aspectratio="t" v:ext="edit"> </o:lock></v:path></v:stroke></v:shapetype><v:shape id="_x0000_i1025" style="width: 66.75pt height: 18pt" type="#_x0000_t75"> <v:imagedata src="file:///C:UsersSHBF9D~1.KAKAppDataLocalTempmsohtmlclip11clip_image001.wmz"> </v:imagedata></v:shape>, and<v:shape id="_x0000_i1026" style="width: 33pt height: 15.75pt" type="#_x0000_t75"> <v:imagedata src="file:///C:UsersSHBF9D~1.KAKAppDataLocalTempmsohtmlclip11clip_image003.wmz"> </v:imagedata></v:shape> CFUmL-1 respectively. The untreated control group was disinfected by oxytetracyclin at concentration of 100 ppm for 24 hours. The haemolymph samples were withdrawn for measuring of THC and TPC within interval hours (2, 6, 12, 24, 48, 96, 144, 240 and 336). The Crayfish samples were then fixed in Davidson fixative. The results showed that the differences of THC value between treatment 4 (95.33±23.16) and control (1.13±.45) were significant (P<0.05) as well as control and treatments 3 (35.33±16.16) and 4 (95.33±23.16) during 2 initial hours. In case of THC the significant difference (P<0.05) was observed between control group (72.33±15.04) and treatment 3 (13.13±5.85) after 48 hours. During 240 hours, also the difference of THC value between control group (80.33±24.94) with treatment 2 (14.67±3.51) was significant (P<0.05). The finding of TPP value showed that there was no significant difference between control group and treatments in during mentioned times (P<0.05). The result of histopathology in heaptopancreas and gill sections showed that hemocyte aggregation and necrosis within pyknosis of nucleus. In lower concentrations of bacteria no pathological changes of heart were observed. In digestive tract no changes were appeared in treatments, but in concentration of 3×108 CFU ml-1 a low aggregation of hemocytes was revealed. <o:p /> Astacus leptodactylus, Aeromonas hydrophilia, Total Hemocyte Count, Total Protein Concentration, Histopathology 644 656 http://jifro.ir/browse.php?a_code=A-10-1-186&slc_lang=en&sid=1 A. SamCookiyaei Drsam.arash@gmail.com 10031947532846004020 10031947532846004020 Yes M. Afsharnasab 10031947532846004021 10031947532846004021 No V. Razavilar 10031947532846004022 10031947532846004022 No A. A. Motalebi 10031947532846004023 10031947532846004023 No S. Kakoolaki 10031947532846004024 10031947532846004024 No Y. Asadpor 10031947532846004025 10031947532846004025 No M. Y. Yahyazade 10031947532846004026 10031947532846004026 No A. Nekuie Fard 10031947532846004027 10031947532846004027 No