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Objective: To study the prevalence and mean intensity of parasites
in Gobiids from south- west of Caspian Sea. Design: Random sampling. Animals: Atotal of 102 samples of four different Gobiid species
including Neogobiusfiuviatilis (No=43), N. kessleri (No=14), N.
caspius (No =33) and N. melanostomus (No=10) were examined
from March to October 2001. Procedures: Cutting the wall of body cavity and removing viscera including intestine, liver, ovaries, testis and etc to isolate the
parasites. Cutting the muscles and finding the cysts of parasites
in them .Fixing the parasites by buffered formalin 10%, clearing
the nematodes by lactophenol, staining the acanthocephals by acetocarmine and identifying them by identification keys. Statististical analysis: Calculating the prevalence, mean intensity,
dominance and range of the parasites by Microsoft Excel and
comparing the differences between species, sexes, age and locations by one way ANOVA and Z Test (P< 0.05). Results: Four different Gobiid species were examined and three
different parasites were isolated. The results as follows: Neogobius
fluviatilis (no=43) was infected with Eustrongylides excisus
(Prevalence P 16.28%, mean intensity ml = 6.29), Dichelyne
minutus (P =27.9%, ml = 3) and Corynosoma strumosum (P= 20. 93%, ml = 24.56), Neogobius kessleri (no =14) was infected with E. excisus (L)(P = 50% ,ml = 10. 71), D. minutus (P = 7.1%, ml
= 16) and C. strumosum (P = 86 %. ml = 34), Neogobius caspius
(no = 33) was infected with E. excisus (L) (p = 18.18 %, ml =1.17) and D. minutus (p=39.39%, ml = 6.62), Neogobius melanostomus (no= 10) was infected with D. minutus (p=20%, ml=3) and C. strumosum (p=l0%,mI=l).
Conclussion: In the present survey, E. excisus (L) and C. strumosum
are reported for the first time from the four different Gobiid species
and D. minutus is reported from N. caspius and N. melanostomus in Iran. It was found that Gobiids can transmit the C. strumosum
as well as E. excisus (L) to the other fish species such as sturgeons.