Comparative growth performance of marine Tilapia (Oreochromis niloticus, L.) cultured in hapa nets at different stocking densities using animal and plant protein diets

Abstract

Aquaculture as an enterprise is hampered by the high cost of fish-based protein diets which account for 30 - 70% of the production cost. Alternative plant-based protein diets are paramount in guiding fish farmers on feed efficacy and fish stocking densities. This study analyzed the growth performance of marine acclimatized Nile tilapia (Oreochromis niloticus) using fish meal (animal protein), soybean (plant protein) and wheat bran (control) formulated diets. Nile tilapia fingerlings weighing 13 -17 g were cultured in hapa nets in three concrete-based ponds at stocking densities of 15 fish/m3, 10 fish/m3 and 5 fish/m3 for each feed treatment. Monitoring of water quality parameters (temperature, dissolved oxygen (DO), and salinity), as well as the initial and final fish body length and weight, was done fortnightly during the experimental period. Two-way ANOVA was used to determine if stocking density and feed treatment(s) had a significant effect on fish growth performance. Weight gain was highest in fingerlings cultured using the soybean- formulated diet (10.28 ± 2.44 g). Marine acclimatized O. niloticus fingerlings had a high feed utilization for soybean meal. The stocking density of 5 fish/m3 recorded the highest percentage survival rate of 85.6% on wheat bran treatment. An optimal stocking density of 5 fish/m3 is therefore recommended to optimize and maximize their fish production.