Nutritional Evaluation of Tropical Forage Grass Alone and Grass-Legume Diets to Reduce in vitro Methane Production

Forage grass nutritional quality directly affects animal feed intake, productivity, and enteric methane (CH 4 ) emissions. This study evaluated the quality, in vitro CH emission potential, optimization of diets based on two widely grown tropical forage grasses either alone or mixed with legumes. The Urochloa hybrid cv. Cayman (UHC) U. brizantha Toledo (UBT), which typically have low concentrations crude protein (CP), were incubated legumes Canavalia brasiliensis (CB) Leucaena diversifolia (LD), higher CP concentrations. Substitution 30% dry matter (DM) CB LD did not affect gas production DM degradability. After 96 h incubation, accumulated was 87.3 mg g ?1 107.7 for (UHC UBT, respectively), 100.7 113.2 combined (70% grass, 15% CB, LD). Diets that (CB LC) UBT) had contents, gross, metabolizable energy (GE, ME, respectively) densities, as well lower neutral detergent fiber (NDF) acid lignin (ADL). ME variables such NFD, tannins (T), showed a positive correlation net production, while ruminal digestibility affected by CP, ADL, T, GE. Optimal ratios components ruminant to reduce rumen increase content found mixtures consisting 60% (either UHC UBT), 10% LD. However, this ratio result decrease production.