Effect of replacing maize with pride of barbados (Delonix regia) seed meal on growth performance, carcass, serum and haematological indices of rabbits
Thirty growing rabbits with mean body weight of 516.67g were used in a feeding trial that lasted for 56 days. The animals were randomly distributed into five (5) dietary treatment groups consisting of six (6) animals per group. Each treatment group was replicated six (6) times with individually housed rabbit per replicate. The five dietary treatments contained 0, 25, 50, 75 and 100% replacement levels of Delonix regia seed meal (DRSM) for maize in a completely randomized design experiment. The parameters investigated during the study were: feed intake, weight gain, feed conversion ratio and feed cost. At the end of the feeding trial, blood samples were collected from the animals through the ear vein for haematology and serum biochemistry. Fifteen (15) animals at the rate of 3 animals per dietary treatment were stunned and sacrificed for the determination of carcass analysis. Samples of visceral organs and primal parts were collected from the animals for carcass yield evaluation. Data obtained were subjected to one-way analysis of variance. The inclusion of DRSM in rabbit diets did not significantly (p>0.05) influence the daily feed intake, weight gain and feed conversion ratio of the animals. The carcass parameters except the forelegs and all the organ weights were not significantly (p<0.05) affected by the dietary treatments. The highest value (3.85%) of the forelegs was obtained in treatment 4 (75% DRSM). The corresponding values of 3.35, 3.39 and 3.40 respectively for animals in treatments 1, 2 and 5 were similar but lower than that on treatment 4 and higher than 3.19% of treatment 3. Feeding of DRSM to rabbits did not show any significant (p>0.05) variation in both the haematological and biochemical components of the rabbits studied except the globulin. The globulins (g/dl) were 1.50, 3.0, 1.70, 3.30 and 1.75 respectively for animals on treatment 1, 2, 3, 4 and 5. All these haematological and serum biochemical parameters were within the normal physiological ranges for rabbits. Cost per Kg feed and cost of feed per Kg live weight decreased significantly (p<0.05) with increased replacement levels of DRSM for maize in the diets with 100% substitution having the least cost. The results suggest that DRSM could completely replace maize (up to 100%) without any deleterious effect on the growth performance, carcass, haematology and serum biochemistry of rabbits. Therefore DRSM may be a panacea to high cost of maize and can be recommended for rabbit farmers.
Keywords: Delonix regia seed meal, growth, carcass yield, organ weights, blood parameters