Evaluación de la producción, composición botánica y contenido nutricional de pastos nativos en dos épocas del año en altiplano

Abstract

The objectives of this research were to determine the availability of DM, botanical composition and NV of the main grassland, the "chilliguar" was measured in the highlands. The botanical composition was estimated using the point-quadrant method. The reference material (grass) was collected from the study site and taxonomically identified. Forage availability (kg DM/ha) was measured at the beginning, middle and end of the rainy season, and in the middle of the dry period. The harvested material was mixed, dried, ground and analyzed for DM, CP, ash, NDF, ADF, and ME. The botanical composition was dominated by F. dolichophylla (23.8 to 36.5 %), M. fastigiata (8.2 to 12.8 %), S. ichu (3.4 to 11.4 %), N. meyeniana (6.6 to 8.1 %), B. boliviensis (2.5 to 7.8 %), A. pinnata (0.1 to 12.1 %), T. amabile (0.0 to 10.5 %), B. unioloides (2.9 to 4.4 %), C. heterofila (1.7 to 4.8 %) and others. The availability of DM varied between 766 and 2154 kg/ha in rainy season and 603 kg/ha in dry season. There was a wide variability in chemical composition between species and seasons. For all species, at the beginning of the rainy season increased forage quality including increased CP, and lower in NFD concentrations, whereas end of the rainy period and especially in the dry season reduced forage quality with declines in CP and increases in NDF and ADF concentration. In conclusion, the yield and nutrient concentration of native pasture show a high varia- bility between both seasons.