Survey of parasitic fauna of some fishes from Osun river, Osun state, southwestern, Nigeria

This study survey the parasitic fauna of some fishes collected from Osun river, Osun State Southwestern Nigeria with aims of evaluating the prevalence, intensity, pattern and distribution of parasites among the collected fishes. A total of 258 fish specimens consisting of 9 species belonging to 7 families were procured by fishermen between March and August, 2021 with the use of cast net. Fish samples were examined, dissected and parasites were removed, identified and counted by employing standard techniques in parasitology. A total of 49 out of 258 collected fishes were infected with ten different parasites with an overall prevalence of 22.9%. The recovered parasites include four cestodes (30%), two digenetic trematode (23.23%), one monogenean, (1.01%), one acanthocephalan (8.08%), one secernetean (32.32%) and one nematode (5.05%). Generally, parasitic prevalence was not size dependent and the female fishes were observed to be more parasitized than male (p˃0.05). The mean intensity and abundance of parasites were higher in the stomach and intestine than the gills. Fish parasitism is one of the major problems facing fish production and could be sustained with high degree of pollution as indicated in this study. Hence pollution control and regular examination of the water bodies should be advocated to prevent low fish performance and production.