Amulejoye F.D.*, Ajibare A.O.1, Arosoye A.S.2, Adegeye A.T.1
1Department of Fisheries and Aquaculture Technology, Olusegun Agagu University of Science and Technology Okitipupa, Nigeria
2Department of Biological Sciences, Olusegun Agagu University of Science and Technology Okitipupa, Nigeria
(Manuscript received 17 February 2022; accepted for publication 29 August 2022)
Abstract. Fish parasites immensely affect fish production given their potential impact on profitability and also cause of zoonotic diseases in many parts of the world. This study therefore investigated the effect of fish parasites on growth and well-being. It also evaluated the body variation between parasitized and non- parasitized fish. The study was carried out in five rivers from Ipare, Aboto, Alape, Igbanran and Igbokoda. The length of parasitized fish samples was 13.00±1.26 cm, 14.02±1.94 cm and 13.51±1.67 cm in male, female and combined sexes, respectively, while the weight was 43.29±12.51 g, 53.86±21.52 g and 48.57±17.92 g in male, female and combined sexes, respectively. Also, the average total length (TL) of the non-parasitized fish was 12.92±1.13 cm, 14.72±1.53 cm and 13.67±1.57 cm in male, female and combined sexes, respectively, while the weight was 38.86±9.33 g, 62.09±16.50 g and 48.49±17.12 g in male, female and combined sexes, respectively. The regression coefficient (b) of length and weight of parasitized samples was b=2.12 (male), b=2.15 (female) and b=2.64 (combined sexes), while the regression coefficient ‘b’ recorded for the length-weight relationship of non-parasitized samples was 3.25, 2.49 and 2.78 for male, female and combined sexes, respectively, indicating allometric growth. Also, Senga sp. and Nematodes were the most prevalent parasites with average volume of 2.33±0.58 and 2.00±0.00 on both male and female fish, respectively. The regression analysis revealed that the occurrence of parasites did not have significant effect (P>0.05) on the length and weight of S. melanotheron from Ilaje Local Government Area of Ondo State, Nigeria. This study also established similarity in morphology among populations of male and female as well as parasitized and non-parasitized Sarotherodon melanotheron from the study area.