Abstract

The structural features of the Karoon fish, as well as identification of their monogenean parasites have not been adequately described in the past. The main goal of this survey was based on the finding of the monogenean parasites and their prevalence in Barbus grypus and Barbus sharpeyi as well as their pathological effects on the branchiae of infected fish. Overall 102 B. grypus and 10 B. sharpeyi were captured from the Karoon River. All parts of branchiae were searched under the microscope. The collected monogenean parasites were mounted and fixed by ammonion picrate and glycerine jelly.

This is the first report on the presence of Gyrodactylus sprostonea and Paradiplozoon sp. In Barbus grypus as well as Dactylogyrus carassobarbi and D. anchoratus in Barbus sharpeyi. The monogenean parasites were found on barbus fish throughout the year but the number of these parasites were significantly greater in spring and summer when the weather was much warmer than other seasons. All fish harbored D. povlovsky. This parasite was the most abundant species in all infected fish. However, the number of Paradiplozoon sp. in B. grypus and those of D. barbioides was the lowest among the other parasites of the examined fish.

During examination of the first left and right branchiae in fish, aged less than one year, it was noticed that: a) The number of parasites was less than the number of those in fish aged more than one year. There was no difference in the number of parasites attached to the left and right branchiae. Generally branchial lesions due to monogenean parasites consisted of epithelial cell hyperplasia, cellular infiltration and blood vessel dilatation in the branchiae.

Acknowledgement

The authors wish to thank Professor A. V. Gusev for identification of parasites.