Evaluación de la digestibilidad del maíz forrajero in vivo, en toretes Holstein y sus cruces.

Abstract

The study evaluated the digestibility of forage corn silage enriched with 0.3% urea on productive parameters in cattle; for this purpose, 3 Holstein bulls, six months old, were assigned to a comparative experiment between corn silage and traditional forage for two months. The experimental units were placed in metabolic cages to evaluate in vivo digestibility, using the total feces collection method for 96 hours after a 15-day adaptation period to each feed ration. The variables studied were: digestibility, productive parameters, and ruminal kinetics. The results showed no statistical difference (p>0.05) between treatments on effective parameters and feed dry matter digestibility; however, crude fiber and crude protein digestibility showed statistical difference (p<0.05) at 96 hours of analysis, with silage reaching a fiber digestibility of 86.33% and protein digestibility of 70.57%. The rumen kinetic variables registered a difference (p<0.05) on acetic and butyric acid, reaching the highest values for forage with 65.90 and 10.63%, respectively. The cost-benefit ratio of the portion with silage was $ 0.70/Kg of BW. It is concluded that corn silage with 0.3% urea added to the cattle feed ration does not positively affect productive parameters and costbenefit ratio, showing improvements in fiber and protein digestibility. Keywords: in vivo, digestibility, hey, silage