The Effect of Diet with Different Inclusion Levels of Tigernut (Cyperus esculentus Lativum) on the Growth Performance of Clarias gariepinus Fingerlings

The growth performance of the African catfish, Clarias gariepinus fed with different inclusion levels of processed tiger nut was studied for 168 days (24 weeks). A total of 144 catfish fingerlings with 0.66±0.12 g mean weight and 3.45±0.24 cm mean total length were collected from the University of Calabar Fish Farm, Calabar, Cross River State, Nigeria. Eighteen (18) rectangular plastic tanks were used for this study. Tigernut seeds (Cyperus esculentus) were purchased in Bogobiri, Calabar, Cross River State. The tiger nut seeds were sundried for fourteen (14) days prior to milling to produce tigernut meal. The drying process was done to reduce excess moisture so as to prevent unpleasant smell, stale taste and growth of fungus as well as to minimize the presence of cyanogenic glycosides. The dried nuts were ground into fine powder and analysed for proximate composition in the Department of Biochemistry, University of Calabar. Complete Randomized Block Design (CRBD) consisting of 18 treatments was adopted for the study. Triplicate culture tanks in treated (L25-L100), and control groups (L0 and Ac) were stocked with eight fingerlings per square meter, respectively. Weight gain, specific growth rate (SGR), feed efficiency (FE) and feed conversion ratio (FCR) of catfish in different treatments were estimated. Five isonitrogenous diets were formulated to contain 0, 25, 50, 75 and 100% tiger nuts to replace the equal weight of fish meal. Commercial fish feed (Coppens) was used as a control feed. All the diets were fed to the catfish fingerlings in triplicate for 24 weeks. The results revealed that optimum requirement of tiger nut level in the formulation of practical diets for improved growth of C. gariepinus was 25% having the highest mean weight gain (42.3±0.68) and feed efficiency (23.50±0.18). Therefore, it is concluded that tigernut meal could be incorporated in C. gariepinus diet at 25% level without any negative effect on growth.