Degradabilidade in situ de estratos de capim-Mombaça adubado com diferentes fontes de fósforo, em pastejo

Abstract

This work was carried out with the objective of determining the degradability of strata of Panicum maximum Jacq cv. Mombaça. The experiment consisted of a random design with split-plot, with three repetitions. The treatments were phosphorus sources: Yoorin® and simple super phosphate 〈 triple super phosphate and Control (without phosphorus) and three pasture strata: 20-40; 40-60 and above 60 cm. In the treatments with phosphorus, 140 kg ha-1 of P2O5 was applied to the planting. After collection of the vegetative material, it was taken to the laboratory and separated into leaf lamina and stem 〈 sheath fractions. After drying and grinding (5 mm) of the fractions, they were incubated in castrated male bovines, for the periods of 96, 48, 24, 6 and 0 hours. The phosphorus sources did not modify the dry mass, crude protein, potential and effective degradability (2, 5, 8% of flow rate) of Mombaça grass. In the strata, the dry matter and crude protein degradability of fractions a, b and c and the potential and effective dry matter degradability and effective crude protein degradability was higher in the strata (above 40 cm).