Prevalence, intensity and influence of size and seasons on parasites of Oreochromis niloticus in Ekiti State Dams, Southwest, Nigeria

Abstract

Fish are subject to various contaminants and environmental contradictions in the aquatic environment that convey stress on them, making them vulnerable to parasites. Therefore, this study was designed to investigative the prevalence and intensity of parasitic infections in Oreochromis niloticus that are of dietary and financial values in Ekiti State. 540 specimens of O. niloticus with different lengths and weights were indiscriminately procured from fishermen at Egbe, Ero and Ureje dams, Ekiti state between November, 2018 and October, 2019. Standard techniques for parasitology were employed in the study. Fish samples were examined, dissected and parasites were removed, identified and counted. Total parasites of 308 (16 genera), 275 (10 genera) and 468 (13 genera) were collected from Egbe, Ero and Ureje dams respectively. The total parasite prevalence was 53.3, 58.3 and 55.5% for Egbe, Ero and Ureje dams respectively. In this investigation, parasite prevalence associated significantly at P < 0.05 with body length and weight in Egbe, Ero and Ureje dams. This indicates the procurement of parasite by age. The mean intensity and abundance of parasites in the three dams were higher significantly at P < 0.05 in rainy season in comparison to dry season. Irrespective of seasons, the parasite abundance and the mean intensity were higher significantly at P < 0.05 in Ureje dam in comparison to Egbe and Ero dams. High degree of pollution normally sustain parasite load as indicated in this study and could diminish fish performance and production. Hence, pollution control and regular examination of the water bodies should be advocated.