The objective was to evaluate apparent digestibility of nutrients and the mean retention time of high-moisture grains of sorghum with low (SLT) and high (SHT) tannin submitted to two processing during ensilage, grinding and rolling. There were used four castrated male horses, crossbred. It was used randomized block by design for four replications, totalizing four repetitions for each treatment. The treatments consisted of SLT e SHT submitted to two processing during ensilage, griding and rolling, in 2 x 2 factorial arrangement tested (2 sorghum genotypes and 2 processing). The daily DM intake was 2% body weight, this way the test-diets were composited by 30% SLT and 70% of hay. There observed differences (P<0.05) between SLT and SHT, as like, of processing method, in that best results were for grinding-SLT, whose means values were to DCDM, DCOM, DCCE, DCCP and DCStarch of 83.82, 83.91, 85.17, 86.56 e 84.72%. Furthermore, not identified significant effect between the grains studied, as well as the processing, on the mean retention time, with an average of 17.5 h. It was concluded that the grinding of grain sorghum silage increases nutrient digestibility. The mean retention time in horses presented similar among grain sorghum silages as rolled and grinded.
grinding; horse; mean retention time; mobile nylon bag; rolling