A trial was accomplished with the objective to verify the effect of the coated or common urea supplementation on the utilization of low quality hay in steers. The treatments were: hay + mineral supplement; hay + protein supplement with common urea; hay + protein supplement with coated urea formula 1; hay + protein supplement with coated urea formula 2. Tifton (Cynodon dactylon L.) hay of low quality (CP: 4.62%, NDF: 83.46%) was used. The measures were: digestibility, intake and digestive kinetics. The relation between degradable intake protein and digestible organic mater intake was highest (P<0.05) for the treatments supplemented with degradable intake protein (DIP); however, the increase of this relation did not modify the other parameters. The others data of intake, digestibility and passage rate were not affected by the treatments (P>0.05) when compared the supplemented or not supplemented diets with DIP and in the same way, when compared the non-protein nitrogen sources. The ruminal degradable protein supplementation was not effective for modifying the studied parameters, as well as, the coated urea sources showed to be similar to the common urea.
digesta kinetics; digestibility; intake; nitrogen; protein; supplementation
