Degradación ruminal en bovinos de la materia seca de Sorghastrum setosum a diferentes edades en época otoñal

Abstract

To evaluate ruminal dry matter (DM) degradation of Sorghastrum setosum in bovine during autumn, samples from 15, 30 and 45 day regrow were cut. Ruminal-cannulated, 550 kg average liveweight steers were used to incubate in situ dacron bags at the following incubation times: 0, 3, 6, 12, 24, 48, 72 and 120 h. Bags were taken out of the rumen at the same time and dried at 60°C for 72 h and weighted. Weight loss was assumed as disappearance of DM from the rumen. Data were analyzed by the GLM procedure of the SAS package. Soluble fraction, degradation rate of fraction, ruminal effective degradation of DM at 2 and 4% passage rate, were not affected (p>0.05) by regrow time. A trend (p= 0.09) was observed for lag time among regrow time. It was concluded that during autumn, cutting time did not affect ruminal DM degradation of Sorghastrum setosum.