De Boever J L, Blok M C, Millet S, Vanacker J, De Campeneere S
1Animal Sciences Unit,ILVO (Institute for Agriculture and Fisheries Research),9090 Melle,Belgium.
2Product Board Animal Feed,2719EK Zoetermeer,The Netherlands.
Animal. 2014 Nov;8(11):1839-50. doi: 10.1017/S1751731114001815. Epub 2014 Jul 28.
The chemical composition inclusive amino acids (AAs) and the energy and protein value of three wheat, three maize and seven blend (mainly wheat) dried distillers grains and solubles (DDGS) were determined. The net energy for lactation (NEL) was derived from digestion coefficients obtained with sheep. The digestible protein in the intestines (DVE) and the degraded protein balance (OEB) were determined by nylon bag incubations in the rumen and the intestines of cannulated cows. Additional chemical parameters like acid-detergent insoluble CP (ADICP), protein solubility in water, in borate-phosphate buffer and in pepsin-HCl, in vitro digestibility (cellulase, protease, rumen fluid) and colour scores (L*, a*, b*) were evaluated as potential predictors of the energy and protein value. Compared to wheat DDGS (WDDGS), maize DDGS (MDDGS) had a higher NEL-value (8.49 v. 7.38 MJ/kg DM), a higher DVE-content (216 v. 198 g/kg DM) and a lower OEB-value (14 v. 66 g/kg DM). The higher energy value of MDDGS was mainly due to the higher crude fat (CFA) content (145 v. 76 g/kg DM) and also to better digestible cell-walls, whereas the higher protein value was mainly due to the higher percentage of rumen bypass protein (RBP: 69.8 v. 55.6%). The NEL-value of blend DDGS (BDDGS) was in between that of the pure DDGS-types, whereas its DVE-value was similar to MDDGS. Although lower in CP and total AAs, MDDGS provided a similar amount of essential AAs as the other DDGS-types. Lysine content was most reduced in the production of WDDGS and cysteine in MDDGS. Fat content explained 68.6% of the variation in NEL, with hemicellulose and crude ash as extra explaining variables. The best predictor for RBP as well as for OEB was the protein solubility in pepsin-HCl (R 2=77.3% and 83.5%). Intestinal digestibility of RBP could best be predicted by ADF (R 3=73.6%) and the combination of CFA and NDF could explain 60.2% of the variation in the content of absorbable microbial protein. The availability of AAs could accurately be predicted from the rumen bypass and intestinal digestibility of CP.
测定了三种小麦、三种玉米和七种混合（主要是小麦）干酒糟及其可溶物（DDGS）的化学成分（包括氨基酸）、能量和蛋白质价值。泌乳净能（NEL）由绵羊的消化系数得出。肠道可消化蛋白质（DVE）和降解蛋白质平衡（OEB）通过在瘤胃和有瘘管奶牛的肠道中进行尼龙袋培养来测定。还评估了其他化学参数，如酸性洗涤不溶性粗蛋白（ADICP）、蛋白质在水中、硼酸盐 - 磷酸盐缓冲液和胃蛋白酶 - 盐酸中的溶解度、体外消化率（纤维素酶、蛋白酶、瘤胃液）以及颜色评分（L*、a*、b*），作为能量和蛋白质价值的潜在预测指标。与小麦DDGS（WDDGS）相比，玉米DDGS（MDDGS）具有更高的NEL值（8.49对7.38 MJ/kg干物质）、更高的DVE含量（216对198 g/kg干物质）和更低的OEB值（14对66 g/kg干物质）。MDDGS较高的能量值主要归因于较高的粗脂肪（CFA）含量（145对76 g/kg干物质）以及更好的可消化细胞壁，而较高的蛋白质价值主要归因于瘤胃旁路蛋白（RBP）的比例更高（69.8对55.6%）。混合DDGS（BDDGS）的NEL值介于纯DDGS类型之间，而其DVE值与MDDGS相似。尽管MDDGS的粗蛋白和总氨基酸含量较低，但它提供的必需氨基酸量与其他DDGS类型相似。赖氨酸含量在WDDGS生产中减少最多，半胱氨酸在MDDGS生产中减少最多。脂肪含量解释了NEL变化的68.6%，半纤维素和粗灰分作为额外的解释变量。胃蛋白酶 - 盐酸中蛋白质的溶解度是RBP以及OEB的最佳预测指标（R² = 77.3%和83.5%）。ADF能最好地预测RBP的肠道消化率（R³ = 73.6%），CFA和NDF的组合可以解释可吸收微生物蛋白含量变化的60.2%。氨基酸的可利用性可以从CP的瘤胃旁路和肠道消化率准确预测。
Zotero 插件