بررسي ميزان شيوع و شدت آلودگي هاي انگلي ماهي سوف سفيد (sander lucioperca) درياي خزر (سواحل بندر انزلي )

Parasite infection in zander {Sander lucioperca) of Caspian Sea in the Anzali Coast

To study parasitic infections of Caspian sea white zander (sander lucioperca) during fishing season of 1387, Zander fish was taken from south coasts of Caspian sea in Anzaly lagoons coasts and transferred lively to aquaculture research center of inner waters. The aim of investigation of Caspian Sea white zander in period of 6 months from fall to winter of 1387, was study of parasitic infections condition in zander fish as well as determination of outbreak amount, severity of infection, abundance, and index of parasitic prevalence. Fish was studied after bioassay according to common methods of autopsy. 10% formalin was used to fix parasites, zilen ethanol was used to trans parent nematodes and Carmann alom dye was used to stain other parasites. Then parasites were recognized using valid recognition keys. In present study, parasite species isolated from white zander were. Eustrongylides excises, Achtheres percarum, Trichodina sp, Dactylogyrus sp, Diplostomum spathaceum. According to results, maximum outbreak (25%), maximum average virulence (4.75 ±0.35 pieces), maximum average frequency (1.18 + 0.37 pieces) and maximum parasite number amplitude (3-7 pieces) were related to Trichodina sp. And minimum outbreak (3.12%) , minimum average frequency (0.03 ± 0 pieces), minimum average virulence (1 ± 0 pieces) and minimum parasite number amplitude (0.1 pieces) were related to Dactylogyrus sp.Meanuwhile, it is for first time after 30 years that Achtheres perarum is introduced from white zander fish as a new lost.