Estimativa da degradabilidade ruminal de quatro genótipos de sorgo (<em>Sorghum bicolor</em> (L.) Moench) utilizando a técnica <em>in situ</em>

Abstract

RESUMO. O experimento foi conduzido com o objetivo de avaliar a degradabilidade in situ da matéria seca (MS), da fibra em detergente neutro (FDN) ABSTRACT. Estimation of ruminal degradability of four genotypes of sorghum (Sorghum bicolor (L.) Moench) using in situ technique. This experiment was carried out to evaluate "in situ" degradability of dry matter, neutral detergent fiber (NDF) and acid detergent fiber (ADF) of four sorghum genotypes (ATF53*9929036; ATF54*9929036; 217*9929012 and VOLUMAX). Four Holstein cows with ruminal fistula were fed on sorghum silage "ad libitum", and 2.0 kg of concentrate. The animals were alloted in a randomized block design, with four replicates, in a split plot arrangement. The genotypes were considered the parcels and the incubation time the sub-parcels. The higher effective dry matter degradability were found in VOLUMAX genotype, (56.22; 53.35 and 50.90%) for all passage rates, (2; 5 and 8%/h, respectively). The genotypes ATF53*992903 and ATF54*9929036 showed higher NDF effective degradability, 32.17 and 33.47% respectively, and ADF effective degradability, 34.81 and 35.50%, at 2%/h passage rate.