Evaluación del grano de arroz con cáscara como ingrediente de raciones de recría para vacunos manejados en confinamiento

The experiment was conducted at the Intensive Meat Production Unit (UPIC) of the Mario A. Cassinoni Experimental Station (EEMAC) in Paysandú, Uruguay, from July 16, 2023, to September 26, 2023. The main objective was to characterize the nutritional value of Rice Husk Grain (GACC) as an ingredient in the rearing rations used in feedlots. This involved describing growth curves, quantifying live weight gain, characterizing dry matter intake, and measuring the effect on digestibility and feed conversion efficiency. Thirty-two Hereford heifers, with an average weight of 272 kg ± 26 kg, born in the spring of 2021 and weaned early in the feedlot, were used. The animals were housed in 32 individual open-air pens and were randomly assigned to four completely mixed rations (RTM) without long fiber, differing in the inclusion level of GACC in substitution for GS, (0% GACC and 45% GS), (15% GACC and 30% GS), (30% GACC and 15% GS), and (45% GACC and 0% GS), expressed on a dry matter basis. The substitution of sorghum grain with GACC in heifer diets did not generate significant changes in intake, weight gain, or feed conversion efficiency. Despite observed differences in digestibility, these did not influence intake, suggesting the presence of intrinsic factors explaining conversion efficiency in different treatments.