Annual Research & Review in Biology

35 million people in Nigeria and other Sub-Saharan African nations rely entirely or partially on fisheries and aquaculture as their primary source of income and food. This study was to determine the occurrence of protozoan on Clarias gariepinus. Total of 506 sample of both Adult and juvenile of Clarias gariepinus were purchased from Fishermen at Omi Dam in Omi from January–December, 2022. This study was done in both dry and rainy season, parasites species were looked out for in the gills, skin, operculum, muscle, liver, gut, intestine and stomach of Clarias gariepinus. Protozoans were isolated using a binocular lens to check for and subsequently followed by scraping of the protozoans and were isolated using forceps and subsequently viewed under a dissecting microscope and photomicrograph was used at x400 objectives. Identification was done using Parasitic Fauna of Fresh Water Fishes Ukrianian (S.S.R.). 102 fishes were infected with parasites and prevalence of 20.16% out of which is 38 protozoans. Six protozoan species were encountered during this study. Ichthyophthirius multifilis was most prevalent; Trypanosoma cobitis was also discovered during this study. Other protozoans include Eimeria rivirei, Myxosoma branchialis, Myxidium oviforme and Chloromyxum mucronatum). Parasites can cause weight loss, debilitation and mortality, eventually leading to low productivity. Fish farmers should be conscious of the effect of these fish parasites and put appropriate measures for the control such as monitoring fish health and water quality.