CHEMICAL COMPOSITION, IN VITRO RUMEN FERMENTATION, AND DIGESTIBILITY OF SELECTED BROWSE SPECIES BY BUFFALOES (Bubalus bubalis L.) AT A SEMI-DECIDUOUS FOREST IN VENEZUELA

摘要

To determine the chemical composition and nutritive value of selected browse species by buffaloes (Bubalus bubalis L.) in a silvopastoral system at a semi-deciduous tropical forest (SDTF), epidermal fragments in fecal samples from 14 males of Murrah breed were evaluated. The animals grazed for 91 days in 85 ha located in Portuguesa State, Venezuela, of which 35 ha corresponded to natural grass pastures (969.3 ?± 28.6 kg DM ha-1), and the rest to SDTF with 463 plant ha-1. Eleven botanical families and 22 species were identified, 40.9% belonged to the Fabaceae family. The specie Guazuma ulmifolia (Sterculiaceae) had the highest relative dominancy (60.4%) and an Importance Value Index of 162.6. 60.4% of epidermal fragments corresponded to herbaceous Poaceae, and the rest was distributed among five different species, with the highest occurrence (94.6%) for Samanea saman and Sida acuta. There were differences (P<0.05) among selected species in the proximal composition (40.9 ?± 7.1% dry matter, 16.0 ?± 4.1% crude protein and 2.9 ?± 1.2% ether extract), neutral detergent fiber (41.6 ?± 2.2%), acid detergent fiber (25.9 ?± 3.8%), minerals (1.6 ?± 0.59% Ca and 0.1 ?± 0.02% P), condensed tannins (0.9 ?± 0.7%), potential gas production (67.8 ?± 37.3 ml g-1 DM), and in vitro organic matter digestibility (54.2 ?± 8.0%). In general, the edible fraction of selected browse species evaluated here was similar to other tropical browse forages and confirms the strategic value of this biomass in buffalo nutrition at silvopastoral system. Furthermore, these browse species could be employed in agroforestry systems to achieve a better integration of livestock production in tropical areas.