Fermentation characteristics and bromatological composition of sweet sorghum bagasse silages

SUMARY The aim of this study was to evaluate conservation characteristics of sweet sorghum bagasse silages. The experiment was carried out at Fazenda Rio Manso, an experimental unit of the Federal University of the Jequitinhonha and Mucuri Valleys. Twenty-five sorghum cultivars with three replicates were used in a completely randomized design. The juice was extracted from the plant through an electric mill, generating bagasse, which was ground in a stationary silage machine, added of its panicles, and then introduced into experimental silos. Silages of the varieties BR505; CMSXS629; CMSXS635; CMSXS639; CMSXS643; CMSXS646; V82391 and V82392 presented lower rate of total dry matter recovery and, consequently, higher gas losses. The means of dry matter contents of bagasse and silage were 32.80 and 28.55%, respectively. The cultivars BR501; XBSW80147; BR505; CMSXS629; CMSXS633; CMSXS634; CMSXS635; CMSXS639; CMSXS643; CMSXS644; CMSXS648; BRS601; Sugargraze; V82391; V82392 and V82393 showed higher crude protein levels. The cultivar CMSXS642 presented lower neutral and acid detergent fiber content: 39.23 and 19.23%, respectively. The cultivar XBSW80147 showed lower acid detergent fiber content. Means of 3.49 for pH and 0.96 for water activity were recorded. The cultivars BR501 and BRS601 showed higher values of electrical conductivity: 0.93 and 0.95 S/cm, respectively. Higher levels of ammoniacal nitrogen were only observed in cultivars BR501; CMSXS629; CMSXS636; CMSXS648 and V82392. Sorghum bagasse silages presented adequate conservation inside the silos, according to the evaluated variables.

摘要 本研究旨在评估甜高粱渣青贮饲料的贮藏特性。试验在热基蒂尼奥尼亚和穆库里谷联邦大学（Federal University of the Jequitinhonha and Mucuri Valleys）的试验单元里奥曼索农场开展。本试验采用完全随机设计，选用25个高粱品种，设置3次重复。通过电动研磨机从植株中提取汁液，制备得到甜高粱渣；将渣粕经固定式青贮设备粉碎后，添加对应植株的穗部原料，随后装入试验青贮窖。BR505、CMSXS629、CMSXS635、CMSXS639、CMSXS643、CMSXS646、V82391及V82392这8个品种的青贮饲料干物质总回收率较低，因此气体损失率更高。甜高粱渣及青贮饲料的干物质含量均值分别为32.80%和28.55%。BR501、XBSW80147、BR505、CMSXS629、CMSXS633、CMSXS634、CMSXS635、CMSXS639、CMSXS643、CMSXS644、CMSXS648、BRS601、Sugargraze、V82391、V82392及V82393这16个品种的粗蛋白含量更高。CMSXS642品种的中性洗涤纤维（neutral detergent fiber）与酸性洗涤纤维（acid detergent fiber）含量更低，分别为39.23%和19.23%。XBSW80147品种的酸性洗涤纤维含量最低。试验测得pH均值为3.49，水分活度均值为0.96。BR501与BRS601两个品种的电导率更高，分别为0.93 S/cm和0.95 S/cm。仅在BR501、CMSXS629、CMSXS636、CMSXS648及V82392这5个品种中检测到较高的氨态氮含量。综合所评估的各项指标来看，甜高粱渣青贮饲料在青贮窖内的贮藏效果良好。