ABSTRACT

Aimed with this study was evaluate the increasing levels of crambe crushed, on in vitro digestibility of dry matter (IVDDM), organic matter (IVDOM) and crude protein (IVDCP), parameters of fermentation and kinetics of the cumulative gas production. The crushed crambe were included in the diets at 0; 50; 100; 150 g/kg of DM. There was a quadratic effect of the proportions of crambe crushed in the concentrated supplements on IVDDM and IVDOM (maximum point at 0.25 and 0.91 g Kg^-1 DM, respectively). Total gas production (A + D) was influenced by the presence of crambe crushed with quadratic effect on minimal point on 0.02 g Kg^-1 DM. There was a quadratic effect for pH in the collection times in all diets, the lowest pH values were observed between 4.8 to 8.7 hours. There was a quadratic effect for ammoniacal nitrogen in the collection times in all diets with peaks of NH₃-N production occurred between 4.8 and 6.3 hours after the beginning of the incubation. Concluded that the inclusion of crambe crushed up to 150 g kg^-1 DM in diets for ruminants does not impair the ruminal degradation kinetics.

Key words
byproduct; Crambe abyssinica ; in vitro digestibility; ruminal parameters