Chemical characteristics, degradation kinetics and gas production of arboreal species for ruminants

Abstract

The breeding systems of the small ruminants are extensive in the great majority, in which the animals are created
in areas of native pasture named Caatinga, being necessary the knowledge on the chemical composition and its characteristics
of feed degradation is crucial to increase nutrient use efficiency. Thereat, the objective of this study was to evaluate the
chemical composition, the minerals, the carbohydrates and nitrogenous compounds fractionation, the degradability, in vitro dry
matter digestibility and the in vitro gas production of arboreal species, those are consumed by goats and sheeps. The species
evaluated were Cnidoscolus phyllacanthus (Muell. Arg.) Pax. et K. Hoffman, Mimosa tenuiflora (Willd.) Poiret, Myracrodruon
urundeuva Fr. All., Poincianella bracteosa (Tul.) L. P. Queiroz, Spondias tuberosa Arr. Cam. and Ziziphus joazeiro Mart. It
was found that Mimosa tenuiflora has a higher crude protein quantity (174.9 g.kg-1 DM). Spondias tuberosa and Myracrodruon
urundeuva had the highest values for total carbohydrates compared to the other species analyzed. As for the fractionation of
nitrogenous compounds, the highest proportion of fraction A was found for Cnidoscolus phyllacanthus (375.5 g.kg-1 CP). Among
the species studied, Cnidoscolus phyllacanthus is highlighted with the highest ruminal degradation (61.63%) and dry matter
digestibility (627.1 g.kg-1 DM), reflecting higher gas production (206.02 mL.g-1 DM). Cnidoscolus phyllacanthus, Poincianella
bracteosa and Myracrodruon urundeuva showed a greater availability of nutrients in the rumen which is fundamental to increase
the amount of ruminal microbial protein which reaches the small intestine for use by the animal.