IN VITRO FERMENTATION EFFICIENCY OF MIXTURES OF Cynodon nlemfuensis, Leucaena leucocephala AND TWO ENERGY SOURCES (MAIZE OR SUGAR CANE MOLASSES)

Abstract

The in vitro fermentation efficiency of Cynodon nlemfuensis forage (star grass) and Leucaena leucocephala foliage (leucaena) and two energy sources (i.e. maize and sugar cane molasses) mixture was evaluated. Mixture samples (1 g DM) were incubated for 24 h. All the mixtures were added with 500 mg of polyetilenglycol (PEG). Adding molasses to star grass increased dry matter true digestibility and carbohydrate fermentation (P<0.01), while having a quadratic effect on cell walls digestibility (P<0.01). When an energy source was added to the mixture it has a quadratic effect on gas production (P<0.01). Mixtures of grass or tree with maize resulted in an increase on the total VFA´s concentration. The grass-leucaena and leucaena-maize mixtures reduced the microbial protein biomass (MPB), while the grass-Leucaena-energy sources mixtures tended to increase MPB production. It is concluded that, the use of molasses, under in vitro conditions, improves the fiber digestibility and MPB while, the use of maize increases the VFA´s production.