Investigation on Biochemically Processed Castor Seed Meal in Nutrition and Physiology of Japanese Quails

Abstract

Native de-oiled and treated castor seed meal was subjected to proximate analysis and quantification of anti-nutrients (phytochemicals). Seed cake was treated by biochemical technique of solid state fermentation with <em>Aspergillus niger </em>and addition of calcium oxide (CaO) to give treated castor seed meal (TCSM). One hundred and twenty Japanese quails (<em>Coturnix coturnix japonica</em>) were fed four (4) iso-nitrogemous and iso-caloric diets containing 0, 2.5, 5.0 and 7.5% TCSM corresponding to the diet 1, 2, 3 and 4, respectively. While the feeding trial lasted for 56 days, feed and water were supplied <em>ad libitum</em>. Data on proximate composition showed that raw seed, defatted residue (cake) and the processed castor seed meal contained valuable nutrients like dry matter, crude protein, fat, fibre, mineral matter and soluble carbohydrate (NFE). Phytochemical quantification gave high levels of the anti-nutrients such as ricin, allergens, ricinine in the raw seed. However, levels of these phytochemicals were reduced by defatting and treatments of the cake meal by solid state fermentation, <em>A. niger </em>and CaO. Performance traits indicated decreases in feed intake, weight gain, growth and increases in mortality rates especially on the diet with the highest (7.5%) inclusion of TCSM compared to the control diet (P<0.05). Nutrients retentions on the test feedstuff were not comparable with values on the reference diet on soluble carbohydrate values which decreased with increasing CSM (P<0.05) relative to the control diet. In haematological parameters packed cell volume (PCV) and mean corpuscular hemoglobin (MCH) values on diets with TCSM were exceptionally high relative to the control diet (P<0.05). However, biochemical indices (serum protein, albumin, globulin, albumin:globulin ratio and alkaline phosphatase (ALP) activities were not influenced by dietary CSM (P>0.05). Enzyme activity of aspartate aminotransferase (AST) showed decreasing trend with increasing level of CSM in diets (P<0.05). Profiling electrolytes in the fed quails showed significant variations in concentrations of Ca⁺⁺ and HCO₃^- on TCSM based diets (P<0.05) comparable with the control diet values. Conclusively, despite treating CSM by solid state fermentation with <em>A. niger </em>and CaO addition in this trial, TCSM addition still appears to induce toxic and deleterious effects on the quails. Subsequent works to enable inclusions at acceptable and higher levels after treatments are on-going.