ABSTRACT

Use of plant protein feed utilization of fish is hampered by antinutritional factors (ANF). Feed ANF can be reduced by fermentation. The growth and nutritional effects of novel diets produced by substituting fishmeal (FM) with solid state fermented bambaranut meal (BNM) on African catfish Clarias gariepinus was carried out in this study. Five isonitrogenous and isocalorific diets were produced with FM:BNM inclusion percentages as follows: feeds, Fl, 50:5; F2, 35:20; F3, 20:35; F4, 5:50 and F5, 0:56. There were control diets F6 and F7 made from non fermented BNM. The diet F6 is a variant of Fl, and F7 is a variant of F5. African catfish of average weight 5.14 ± 0.05g were stocked in plastic aquaria of length 36.0cm, width 26 cm, height 25.9cm at 76.1 g aquarium'. There were three replicate aquaria per feed. The fish were fed a! libitum three times a day for 56 days. The performances of these feeds were cross compared with that of a commercial diet Coppens BV Netherlands. The best specific growth rate (SGR) was by catfish fed with Fl, 7.82±0.25 % day' followed by with F6, 7.35± 0 % day' and F2 7.26±0.18 % day 1. There was no difference in the SGR of F2 and F6 (P<0.05). The highest weight gain was by the fish fed with feed Fl, 80.12±0.06g and those fed F2, 71.13±0.03g. The weight gain of fish fed with F6 was 70.87±0.32g. The least AWG was found in the fish feed with ES and F7 with the values 20.96±0.54g and 20.32±0.54g respectively. The food conversion ratio (FCR) was lower and best for the catfish fed with fermented BNM than control. The FCR for F! was 1.24±0.19, 1.34±0.06 and F6 1.52. Fermentation increased the protein and amino acid content of the BNM and also weight gain of fish. The growth and nutritional performance of fish fed with F2 was as good as F! and cost effective with the economic conversion ratio of F1(1.437382) and (F2 0.92214). The growth effects of the feeds suggest that ANF seems to be highly reduced in solid state fermented BNM thereby enhancing catfish growth.