COMPARATIVE INVESTIGATION OF ENDOPARASITES, HEAMOPARASITES AND HEAVY METALS IN CLARIAS GARIEPINUS RAISED IN CONCRETE AND EARTHEN PONDS

Aquaculture serves as a major source of animal protein and livelihood in Nigeria, with Clarias gariepinus (African catfish) being one of the most extensively farmed species. However, its production is often threatened by parasitic infections and environmental contamination, which may affect fish health and food safety. This study investigated the prevalence of haemoparasites, endoparasites, and concentrations of selected heavy metals in C. gariepinus from local concrete and earthen ponds in Ijebu-Igbo, Ogun State, Nigeria. Ten fish samples (five from each pond type) were examined using standard parasitological and analytical methods. Blood smears were prepared and stained with Giemsa for haemoparasite detection, intestinal contents were examined for endoparasites, and fish muscle tissues were analyzed for heavy metals using Atomic Absorption Spectrophotometry (AAS). The results revealed Trypanosoma species as the predominant haemoparasite, with an overall prevalence of 30 %, comprising 40 % in earthen ponds and 20 % in concrete ponds. Endoparasites detected included Cryptobia spp., nematodes, cestodes, and trematodes, with an overall prevalence of 60 %, being higher in earthen ponds (80 %) than in concrete ponds (40 %). The combined prevalence of all parasites was 70 %. Heavy metal analysis indicated mean concentrations of Fe (2.52 ppm), Cu (0.107 ppm), Pb (1.309 ppm), and Zn (1.35 ppm), all of which were below the permissible limits set by WHO, FAO, and NAFDAC. The study concludes that while parasitic infections were more pronounced in fish from earthen ponds, the levels of heavy metals in the fish flesh were within safe limits for human consumption.