Nutritional potential of forage species found in Brazilian Semiarid region

Brazilian Semiarid region is the natural environment of many herbaceous and shrubby plants that can be consumed by ruminants. Our objective was to estimate nutritional potential and CH4 production of forages from Brazilian Semiarid region for ruminant diets. We evaluated Manihot pseudoglazziovii, Mimosa caesapiniifolia, Bauhinia cheilantha, Leucaena leucocephala, Clitorea ternatea and Gliricidia sepium by chemical composition, digestibility and degradation parameters and ruminal fermentation. The fractionation of carbohydrates and proteins was performed based on the Cornell Net Carbohydrate and Protein System. The evaluation of the degradation of organic matter and ruminal fermentation products was performed by the semi-automatic in vitro gas production technique. The ruminal degradability and intestinal digestibility of protein were estimated using the in vitro three stage simulation technique. Clitorea, followed by Leucaena, had the highest concentration of the fraction B2 (potentially digestible fiber) while the concentration did not differ (P>0.05) between the other species. The fractions C were found in greater quantities (P<0.05) in the Mimosa and Bauhinia species. Manihot, Gliricidia and, to a lesser extent, Leucaena, resulted in higher (P<0.05) true degradation of organic matter (g/kg organic matter) and higher partitioning factor (ratio of degradability and gas production). Leucaena showed greater intestinal protein digestibility (g/kg dry matter), especially as a protected source of protein ruminal degradation and available in the intestine. Gliricidia, Leucaena and Manihot showed potential for reducing the production of enteric methane, without compromising the degradation of nutrients, with high digestibility and readily fermentable carbohydrates.