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Objective: To study the prevalence and mean intensity of parasites in Acipenser gueldenstaedti, A. nudiventris. and HuSO huso.
Design: Descriptive study.
Animals: One hundred and two samples of three different sturgeon species of Caspian Sea.
Procedure: Cutting the wall of body cavity and removing viscera including intestine, liver, ovaries, testis and etc to isolate the parasites, fixing the parasites by formal in 10% and the nematodes by ethanol 70%, clearing the nematodes by lactophenol, staining the parasites by acetocarmine and identifying them by parasitic identification keys.
Statistical analysis: Descriptive statistics.
Results: The prevalence and mean intensity of parasites in A.
gueldenstaedti are as follows: Cucllanus sphaerocephalus (prevalence== 6 I.I I %, mean intensity ==5.98), Eustrongylides excisus (L) (P == 15.28%, i == 2.91), Skrjabinopsolus semiarmatus (P==15.28%, i== 2.82), Leptorhynchoides plagicephalus (p==6.94%
i==4.41), Anisakis SP.(L)(P==5.56%, i==1.5), Corynosoma strumosum (p==9.71%, i==9.75). In A. nudiventris five different parasites were collected which the prevalence and mean intensity as follows: Cucullanus sphaerocephalus (prevalence== 75%, mean intensity ==8.75), Skljabinopsolus semiarmatliS (P==68.75% ,i== 47.91), Eustrongylides excisus(L) (P == 31.25%, i == 9.6), Eubothrium acipenserinum (P == 3] .25%, i == 2.8), Lep/orhynchoides plagicephalus (p==6.25% , i==3).
In Huso hliSO. six different parasites were isolated including: Cllcullanus sphaerocephaills (p== 66.67, 1==6.25), Eustrongylides excisus (L) (p==50, 1==109.33), CO/ynosoma strumosum (p==33.33, 1==5.5), Eubothrium acipenserinur (p==33.33, 1==1) ,Anisakis sr. (p==16.67, 1==5) and SkrjabinopsoluS semiarmatus (p==16.67, 1==1).
Conclusion: The parasites of Acipenser gueldenstaedti was similar to A. nudiven/ris and Huso huso which is probably related to their piscivorous feeds. The occurance of parasites which have vertebrated intermediate hosts, such as Eustrongylides excisus (L), COrynosoma strumOSlim and Anisakis SP, in these three sturgeons were more than other sturgeons. The parasites of Acipenser gueldenstaedti and A. nudiventris are reported for the first time from Iran. J. Fac. Vet. Med. Univ. Tehran. 57, 4: 33¬38, 2002.