Proximate composition of selected potential feedstuffs for Nile tilapia (Oreochromis niloticus Linnaeus) production in Kenya

Nutrition is vital in fish farming because feed costs represent 40–50 % of the total variable production costs (SHANG, 1992; CRAIG and HELFRICH, 2002). For several decades, fishmeal has been used as the main source of protein in fish feeds (TACON and JACKSON, 1985; TACON, 1993; EL-SAIDY and GABER, 2004; ALCESTE and JORY, 2000). However, the periodically occurring low availability, competition and continuously fluctuating prices of fishmeal are affecting aquaculture feed production and consequently the profitability (WATANABE, 1988; WATANABE and PONGMANEERAT, 1991; LIM and DOMINAY, 1990). As a result, a lot of effort has been focussed on feed alternatives to fishmeal both from plant and animal protein sources (ELSAIDY and GABER, 2004; EL-SAYED, 1998; FERNANDES et al., 1999; FASAKIN et al., 1999; RINCHARD et al., 2002; HOSSAIN et al., 2002). In order to enhance aquacultural production, improve food security, and reduce the level of poverty in developing