A split-plot design digestion trial was carried out with three rumen-fistulated steers to evaluate the effect of wilting and addition of corn meal on in situ degradability of dry matter (MS), crude protein (CP) and neutral detergent fiber (NDF) of alfalfa silage, using three periods (6, 24 and 96 hours) and six different silages (1-fresh alfalfa; 2-fresh alfalfa with 5% corn meal; 3-fresh alfalfa with 10% corn meal; 4-wilted alfalfa; 5-wilted alfalfa with 5% corn meal and 6-wilted alfalfa with 10% corn meal). The addition of corn meal and wilting treatments presented the highest DM and NDF degradability rates. The wilting reduced (P<0.05) degradation potential, however, addition of corn meal lightly changed the DM degradability. The b FDN fraction increased with addition of corn meal and decreased with wilting. In spite of this, fraction b increased when corn meal was added to wilted forage. Degradation rate increased CP fraction with corn meal addition and decreased with wilting. Addition of corn meal increased degradation rate of CP fraction. It is concluded that wilting decreases alfalfa silage nutrients because it reduces soluble fraction of forage. However this nutrients can be improved with addition of corn meal.
Alfalfa; silage; rumen degradability; dry matter; crude protein; neutral detergent fiber
