Influence of including maize offal in diets on growth, carcass composition and economics of Clarias gariepinus

Aiming at finding cheaper and still efficient feed for aquaculture species 56 days feeding trial was conducted on African catfish (Clarias gariepinus) post fingerlings, fed on five diets with a 40% crude protein target in which maize was replaced with maize offal meal at 0%, 25%, 50%, 75%, and 100% respectively. Ten fish each were stocked in a plastic aquarium tank containing 20 L of water. The fish were fed at 5% body weight divided into two rations ginen at the hours of 8-8:30 am and 5-5:30pm. Growth parameters showed increase with increase in maize offal based diets, with observed weight gains of 72.42, 79.00, 95.92, 130.83 and 65.83 for diets 1, 2, 3, 4, and 5 respectively. Feed conversion ratio (recorded best in 75% maize offal based diet substitution, while the poorest was recorded at 25% maize offal diet replacement, followed by the control diet (100% maize diet). 75% maize offal replacement recorded the highest specific growth rate (p<0.05).There was significant difference (p<0.05) in the ash content, crude fiber and energy level in the fish carcass. The cost of feed used throughout the experimental period was not significantly (p>0.05) influenced by the increasing level of maize offal as a replacement for maize in the diets, as the costs were comparable. However, this study reveals that maize offal meal can successfully replaced maize up to 75% in the diet of Clarias gariepinus post fingerlings without adverse effect on growth, carcass composition and economics.