The Pathological study of gastro intestinal Aspidogaster limacoides Diesing, of the Caspian Sea kutum fish Rutilus frisii kutum (Kamenskii, 1901)

Caspian sea is a land–locked brackish water lake where zoologically characterized by various aquatic animals aquatic animals and different commercially important fish species Shariati [15]. The fishes in the Caspian Sea and its watershed areas include 78 species, and 49 subspecies which belong to 16 fish family. The bulk of Caspian Sea fishes are anadromos and the major commercially important fish species include the bony fish, and a cyprinid fish Rutilus frisii kutum, dwelling mainly along the southern coastal waters of the Caspian Sea. The fish reaches maturity at the Caspian sea is a land – locked brackish water lake where zoologically characterized by variouage of 3 years. In mid-March till April when the water temperature ranges between 12-18 C the matured fish migrate to rivers flow into sea for spawning Shariatee [16]. They tend to feed on phytoplanktons at larval stage while at later stages they turn to shells, chironomid larvae and polychaete worms Vosoughee and Mostageer [18] Mokhayer, [7]. Detected certain species of digenen trematode in kutum fish caught from the sefid-Rood river including Aspidogaster limacoides and Asymphylodora kubanicum Mokhayer [7]. Among parasites, Aspidogaster limacoides constitutes the most prevalent species with a wide range of hosts infesting different cyprinids in the Baltic Sea and the Sea of Azouf Molnar [8] Rahanandeh et al. [12]. The degree and intensity of such parasitic contamination in areas such as foregut, midgut and hindgut were 52%, 32% and 16% respectively (Rahanandeh et al. [12] The present study involved the catch of 25 pieces of Rutilus frisii kutum (800-1400gr) during March-May 2015 through beach seine operations along the southern shores of the Caspian Sea. Following the landing of the sample fish, they were transferred live to the fish health laboratory which was then followed by dissection of the body, removal of their digestive tracts and storage in the 0.6% physiological serum. The samples of gut tissue were obtained based on the procedure introduced by Robert [13] Through microscopic observation, cases including tissue degenerati, hyperplasia, Necrosis, hemorrhage, hyperemia caused by parasite invasion within the gut mucous were identified