Study on prevalence of parasites in Persian sturgeon (Acipenser persicus) spawners in the southwest coasts of the Caspian Sea, 2009

This survey was done on 20 Persian sturgeon (Acipernser persicus) spawners caught in the southwest coasts of the Caspian Sea (Guilan Province) from April through June 2009 to identify the parasitical fauna and prevalence, intensity and dominance of these parasites. The specimens under study were measured and their biometric characteristics were recorded. Standard methods of sampling and parasitological examinations were used to identify parasites in organs (skin, gills, eyes, eggs, liver, gall bladder and digestive tract). In this study, any parasites didnt find in skin and eyes. Diclobothrium armatum Leuckart, 1835 was observed in gills. Four types of internal helminthes parasites were identified in A. persicus brood fish caught in each year that include, Cucullanus sphaerocephalus Rudolphi 1809, Skrjabinopsolus semiarmatus Molin 1858, Eubothrium acipenserinum Cholodkovsky 1918 and Leptorhynchoides plagicephalus Westrumb 1821. It is evident from the results obtained that Cucullanus sphaerocephalus, Skrjabinopsolus semiarmatus showed the highest dominance (83.28%) in the Persian sturgeon brood fish under study. The increase in these two parasite communities may be related to the occurrence of Nereids (polychaeta) and Oligochaeta. Results of Pearson correlation coefficient test showed that there is a direct and positive correlation between age and parasitic counts in A.persicus females and male.