关键词: 水分吸附材料, 象草, 青贮, 发酵品质, 好氧稳定性

Abstract:

In south China， napier grass often has a high moisture content at harvest and as a result the fermentation quality of direct-cut silage is poor. In order to improve the quality of napier grass silage， the effects of various moisture-absorbing roughage materials on the silage fermentation quality and aerobic stability were studied. There were five silage treatments； four of these being napier grass with an added roughage material at 10% fresh grass weight and the fifth a Control （napier grass with no additive）. Roughages tested were rice bran， wheat flour， dried soybean curd residue and wheat bran. The fermentation quality and aerobic stability of the silages were analyzed 60 d after ensiling. It was found that all additive treatments significantly increased the dry matter （DM） content （P<0.01）， reduced the buffering capacity （P<0.05）， and increased the lactic acid content （P<0.01） of the respective silages， compared with the control. The addition of wheat flour significantly increased the concentrations of butyric acid （0.81% DM） and NH₃-N （14.40% TN， P<0.05）； the other roughage additives had no significant effect （P>0.05） on silage quality. The butyric acid and NH₃-N contents of silage with added dried soybean curd residue were only 0.04% DM and 9.75% TN， respectively. After the silage was exposed to the air， the aerobic stabilities of the silages with added wheat flour and dried soybean curd residue were better than the others. Based on multivariate analysis of nutritional characteristics， silage fermentation quality and aerobic stability， the addition of dried soybean curd residue produced the best silage.

Key words: moisture-absorbing material, napier grass, silage, fermentation quality, aerobic stability