Chemical composition of hays of the Caatinga shrub legumes mororó and sabiá from different parts of the plant
Native forages are important feed sources in the northeastern semi-arid region of Brazil. The objective of this study was to evaluate the chemical characteristics of hays made from the native shrub legumes, sabiá (Mimosa caesalpiniifolia Benth.) and mororó [Bauhinia cheilantha (Bong.) Steud.], using different plant fractions, leaves only or leaves plus twigs. Analyses carried out were: concentrations of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), ether extract (EE), ash, total digestible nutrients (TDN) and non-fiber carbohydrates (NFC). Sabiá leaf hay contained greater CP concentration (182 g/kg DM) than mororó leaf hay (126 g/kg DM) but hay made from leaf plus twigs showed similar CP for both legumes (mean 106 g/kg DM). Concentrations of NDF (368 g/kg DM), NFC (418 g/kg DM) and TDN (481 g/kg DM) of mororó leaf hay were superior to those of sabiá leaf hay (465, 258 and 311 g/kg DM, respectively). The findings suggest that these native legumes can be conserved as hay during the growing season to provide a supplementary feed with acceptable nutritive value for feeding during the period of inadequate feed availability and quality in semi-arid Brazil. However, more samples from a range of growth stages and locations are needed to confirm these preliminary findings and to provide data on possible yields, while more feeding studies with ruminants are needed to confirm the preliminary data in terms of liveweight performance.