Alternative feed resources for formulating concentrate diets of rabbits. 2. Jack Bean (Canavalia Ensiformis) seeds.

In an eight-week long feeding and digestibility trial, the acceptable amount of heat-processed (1 h boiling) jack bean seed that can be used to substitute partially for oil cakes (palm kernel and groundnut cakes) in concentrate diets of rabbits was examined (8 rabbits 7-9 week old of local population per treatment). Four diets were formulated to contain O, 10, 20 and 30 % jack bean seed, respectively. The proximate composition of heat-processed jack bean (27.4 % crude protein, 14.2 % crude fibre and 51.1 % nitrogen free extract) showed that it has potential for use in rabbit feeding. Dry matter intake significantly declined with increasing levels of inclusion of jack bean, being 44.0, 46.5, 33.3 and 30.5 g/day at 0, 10, 20 and 30 % levels respectively. Weight gains declined by a non-significant 33.4 % with 20 % jack bean and by a significan! 69.9 % with 30 % jack bean inclusion level relative to the average weight gain of the control (10.6 g/day) and 10 % jack bean diets (11 .1 g/day). Feed conversion efficiency value was similar for the control and 10 and 20 % jack bean diets (average 0.23), but declined by 57 % with 30 % jack bean. The digestibility of DM and nutrients was generally high in ali the diets, varying between 61 and 87 %; digestibility significantly declines with increasing levels of jack bean, being about 15 to 20 % lower with 30 % jack bean diet. There were minor changes in the haematological and sorne serum enzyme parameters of the rabbits, except for the significantly higher levels of white blood cells and lymphocytes in the rabbits on 30 % jack bean diet. Serum proteins (total protein, albumin and globulin) were significantly depressed beyond 10 % inclusion of jack bean. The study demonstrated that good feed intake, digestibility, weight gain and haematological and biochemical responses can be achieved in rabbit with heat-processed jack bean seed replacing expensive oil cakes up to levels of 10 % in their diets and may be up to 20 %. Serum protein levels were depressed at 20 % level and beyond that level weight gains were also appreciably depressed.