Comparison of Two Processing Methods for Pigeon Pea Seeds (Cajanus Cajan) as Protein Source for Broiler Starters

Abstract

The search for alternative plant protein sources in broiler rations is a continuous exercise in Nigeria because of scarcity and high cost of soya bean meal, groundnut cake and fishmeal. The conventional or primary protein feedstuffs are affected by severe competition from humans and industries that command higher priority and higher prices than the compound feed industry. Pigeon pea has a very low human food preference and no industrial use. Its meal has a satisfactory protein ingredient of up to 30% of the whole ration (Springhall et al, 1974; Grimaud, 1988; Tangtaweewipat and Elliott, 1989). Ologhobo (1992) indicated that 25% pigeon pea seed meal adversely affected feed conversion efficiency of broilers because the seeds may have been raw. As with other grain legumes, the seeds contain antinutritional factors like trypsin and protease inhibitors which limit their use in poultry feeding (Grimaud, 1988; Ologhobo, 1992; D'Mello, 1992). Although pigeon pea seeds contain less trypsin and chemotrypsin inhibitors than soya bean (ICRISAT, 1991), some of the wild relatives to which Nigerian variety may belong may contain higher concentrations of protease inhibitors that influence protein digestibility. Pigeon pea seeds contain raffinose and starchyose which are flatulence causing sugars (ICRISAT, 1991). Cooking and other processing methods of grain legumes exert a beneficial effect on the starches and is desirable with fibrous foodstuffs. In this study, boiling was done for 30 min at 100°C beyond which the nutritive value of the seeds would decrease (Elias et al., 1973). Dehulling improves the digestibility of the proteins, lowers tannin content and reduces the crude fibre and calcium content of seeds (Salunkhe et al 1985). Dehulling of cooked pigeon pea seeds also increases the biological value,