Nutritional Evaluation and Effectiveness of Detoxified Jatropha curcas Kernel Meal in Finishing Pig Diets on Biogas and Methane Production from Slurry

Abstract

The purpose of this work was to evaluate Phorbol Ester’s (PE), Total Fenols (TF), Total Tannins (TT), Condensed Tannins (CT), Saponins Content (SPN), amino acids profiles and apparent digestibility of detoxicated Jatropha curcas meal in finishing pigs diets, as well as biogas and methane production by the manure from cross-bred pigs fed this meal. Apparent digestibility coefficients of Dry Matter (DM), Crude Energy (CE), Crude Protein (CP), Crude Fiber (CF) and Ether Extract (EE) were evaluated. Twenty crossbreed pigs with 70±1.95 kg initial weight were allotted in individual metabolic cages, according to body weight in a Complete Randomized Block Design with ten replications per treatment. On the last day of the adaptation phase of the digestibility experiment, the manure were collected and put it in bottles with hydraulic retention time of seven days for further evaluation of biogas and methane produced in liters and liters % of total solids. The content of PE, TF, TT, CT, SPN, were, respectively, 0.06 mg/g, 26.08 and 10.43 equivalent gram of tannic acid, 0.05 equivalent gram of leucocyanidin and 0.005%. The results of apparent digestibility coefficients were 83.80% (DM), 3.500 kcal/kg (CE), 13.45% (CP), 1.5% (CF) and 2.3% (EE). Regarding the generation of biogas and methane of manure from pigs fed detoxified Jatropha curcas meal, biogas production (1201.4, 1089.3 mL/g Total Solids) and methane (246.7 and 218.2 mL/g Total Solids) from manure weren't significantly different (p>0.05) between the treatments. So, concludes that detoxicated Jatropha curcas meal is a promising by-product due its nutritional composition and metabolic response which may be used in finishing pig diets without affecting the generation of renewable energy.