Revista Brasileira de Zootecnia
On-line version ISSN 1806-9290
VALENTE, Bruno Stefano Miranda et al. Chemical composition, digestibility and in situ degradation of sheep diet on Tanzania grass with three defoliation frequencies. R. Bras. Zootec. [online]. 2010, vol.39, n.1, pp. 113-120. ISSN 1806-9290. http://dx.doi.org/10.1590/S1516-35982010000100015.
The objective of this study was to evaluate the chemical composition, digestibility and in situ degradation of dry matter of the diet consumed by sheep grazing on Panicum maximum cv. Tanzania under three defoliation frequencies, determined by the interception of the photosynthetically active radiation in the canopy (PAR) of 85, 95 and 97% on the first and fourth days of the grazing period. A randomized complete design in a 3 × 2 factorial arrangement (three defoliation frequencies and two days grazing), with four replications (poles). To determine the chemical composition, digestibility and an in situ dry matter degradation trial, a grazing simulation was carried out on the 1st and 4th days. Reduced defoliation frequency decreased the chemical composition, digestibility and in situ degradation of the diet. Thus defoliation frequency of tanzania grass is recommended of less or equal to 95% photosynthetically active radiation to maintain pasture quality.
Keywords : Panicum maximum; photosynthetically active radiation interception; production system.