Okure G.P. , Imefon Udo Udo , Afia O.E.

1 Godswill Patrick Okure-Department of Fisheries and Aquatic Environmental Management, University of Uyo, Uyo, 520103, Akwa Ibom State Nigeria
2 Imefon Udo Udo - Department of Fisheries and Aquatic Environmental Management, University of Uyo, Uyo, 520103, Akwa Ibom State Nigeria
3 Ofonime Edet Afia-Department of Fisheries and Aquatic Environmental Management, University of Uyo, Uyo, 520103, Akwa Ibom State Nigeria
Author    Correspondence author
International Journal of Aquaculture, 2024, Vol. 14, No. 5   
Received: 20 Aug., 2024    Accepted: 25 Sep., 2024    Published: 25 Oct., 2024

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The effect of feeding five experimental diets NoRE, 1666RE, 3332RE, 6664RE, 13,328RE containing different vitamin A acetate levels (VA): 0, 1666, 3332, 6664 13328 40, 60 IU kg^-1diet, respectively, on egg quality, egg and liver retinol, ovary estradiol, and larval survival rate of African catfish (Clarias gariepinus) broodstock was studied in a tripodal 60-day feeding trials. These were designated as F0, F1 and F2, making a 180-day feeding experiment. The preliminary phase (F0) was conducted to detoxify the broodstocks of cellular VA. The second and third phases (F1, F0) were conducted to access first and the second spawning seasons. During the preliminary phase experimental fish were fed with the basal diet (control diet) thrice a day three percent (3%) fresh body weight. The mean percentage fertilized egg was significantly higher in fish fed diets 6664 RE and 13328 RE than others and ranged from 73 to 98% for both halves. The mean percentage hatched egg was significantly higher (p<0.05) in fish fed 13,328 IU Kg^-1 than others and ranged from 80 to 100% for both halves. The retinol content in eggs was significantly higher in fish fed 13,328 IU Kg^-1 than others and ranged from 175 to 3884 and 204 and 4022 IU kg^-1 for F1(60) and F2(60) respectively. No retinol was detected in livers. The Estradiol residues significantly (p<0.05) increased with increase concentration and was significantly higher (p<0.05) in F2 (60). Larval survival rate was significantly higher (P<0.05) in fish fed diet 3332 to 13328 RE and was significantly higher in F2 (60) than F1 (60). Retarded growth, poor feed efficiency, abnormal coloration, and bone and fin erosion were observed as signs of VA deficiency in fish fed 0 IU kg⁻¹. No effect of VA excess was observed. On the whole, fortification of brood stock fish diet of C. gariepinus has resulted in positive growth and reproduction parameters. The aquaculture industry should follow the lead of the more advanced poultry industry and begin formulating broodstock and sex-specific rations. Vitamin A dosage as high as 13,328 IU kg^-1 diet is recommended for such ration.

Nutrition; Feed; Growth; Aquaculture; Health