Gutierrez N A, Serão N V L, Kerr B J, Zijlstra R T, Patience J F
Department of Animal Science, Iowa State University, Ames 50011.
USDA-ARS-National Laboratory for Agricultural and the Environment, Ames, IA 50011.
J Anim Sci. 2014 Oct;92(10):4505-17. doi: 10.2527/jas.2013-7265. Epub 2014 Aug 22.
An experiment was conducted to determine a best fitting dietary fiber (DF) component to estimate the effect of DF concentration on the digestibility of energy, DF, and AA and energy value of 9 corn coproducts: corn bran (37.0% total nonstarch polysaccharides [NSP]); corn bran with solubles (17.1% NSP); cooked corn distillers dried grains with solubles (DDGS; 20.4% NSP); reduced oil DDGS (25.0% NSP); uncooked DDGS (22.0% NSP); high protein distillers dried grains (21.9% NSP); dehulled, degermed corn (1.1% NSP); corn germ meal (44.4% NSP); and corn gluten meal (4.9% NSP). A total of 20 growing pigs (initial BW: 25.9 ± 2.5 kg) were fitted with a T-cannula in the distal ileum and allotted to 10 dietary treatment groups in a 4-period incomplete block design with 8 observations per treatment. Treatments included a corn-soybean meal-based basal diet and 9 diets obtained by mixing 70% of the basal diet with 30% of the test ingredient. In tested ingredients, 11 DF components were determined: 1) ADF, 2) NDF, 3) total dietary fiber, 4) hemicellulose, 5) total NSP, 6) NSP arabinose, 7) NSP xylose, 8) NSP mannose, 9) NSP glucose, 10) NSP galactose, and 11) arabinoxylan. The apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of GE, DM, and NDF and the AID of AA of ingredients were measured. A single best fitting DF component was assessed and ranked for each trait, showing that arabinoxylan concentration best explained variance in AID of GE (R(2) = 0.65; cubic, P < 0.01) and DM (R(2) = 0.67; cubic, P < 0.01). The NSP xylose residue best explained variance in ATTD of GE (R(2) = 0.80; cubic, P < 0.01), DM (R(2) = 0.78; cubic, P < 0.01), and NDF (R(2) = 0.63; cubic, P < 0.01); AID of Met (R(2) = 0.40; cubic, P = 0.02), Met + Cys (R(2) = 0.44; cubic, P = 0.04), and Trp (R(2) = 0.11; cubic, P = 0.04); and DE (R(2) = 0.66; linear, P = 0.02) and ME (R(2) = 0.71; cubic, P = 0.01) values. The AID of Lys was not predictable (P > 0.05) from the DF concentration. In conclusion, the arabinoxylan and NSP xylose residue were the DF components that best explained variation due to DF concentration and, with the exception of AID of Lys, can be used to predict the digestibility of energy and DF and the DE and ME values in corn coproducts.
进行了一项实验，以确定最适合的膳食纤维（DF）成分，用于评估DF浓度对9种玉米副产品能量、DF、氨基酸消化率以及能量值的影响。这9种玉米副产品分别是：玉米麸（总非淀粉多糖[NSP]含量为37.0%）；含可溶物的玉米麸（NSP含量为17.1%）；熟玉米干酒糟及其可溶物（DDGS；NSP含量为20.4%）；低油DDGS（NSP含量为25.0%）；生DDGS（NSP含量为22.0%）；高蛋白干酒糟（NSP含量为21.9%）；去皮脱胚玉米（NSP含量为1.1%）；玉米胚芽粕（NSP含量为44.4%）；以及玉米蛋白粉（NSP含量为4.9%）。总共20头生长猪（初始体重：25.9±2.5千克）在回肠末端安装了T型套管，并按照4期不完全区组设计分配到10个日粮处理组，每个处理有8个重复。处理包括以玉米-豆粕为基础的基础日粮，以及通过将70%的基础日粮与30%的试验成分混合得到的9种日粮。在受试成分中，测定了11种DF成分：1）酸性洗涤纤维（ADF），2）中性洗涤纤维（NDF），3）总膳食纤维，4）半纤维素，5）总NSP，6）NSP阿拉伯糖，7）NSP木糖，8）NSP甘露糖，9）NSP葡萄糖，10）NSP半乳糖，11）阿拉伯木聚糖。测定了各成分的总能（GE）、干物质（DM）和NDF的表观回肠消化率（AID）和表观全肠道消化率（ATTD）以及氨基酸的AID。针对每个性状评估并排序了单一最佳拟合DF成分，结果表明阿拉伯木聚糖浓度最能解释GE的AID（R² = 0.65；三次方，P < 0.01）和DM的AID（R² = 0.67；三次方，P < 0.01）的变异。NSP木糖残基最能解释GE的ATTD（R² = 0.80；三次方，P < 0.01）、DM的ATTD（R² = 0.78；三次方，P < 0.01）和NDF的ATTD（R² = 0.63；三次方，P < 0.01）的变异；蛋氨酸（Met）的AID（R² = 0.40；三次方，P = 0.02）、Met + 半胱氨酸（Cys）的AID（R² = 0.44；三次方，P = 0.04）和色氨酸（Trp）的AID（R² = 0.11；三次方，P = 0.04）的变异；以及消化能（DE）（R² = 0.66；线性，P = 0.02）和代谢能（ME）（R² = 0.71；三次方，P = 0.01）值的变异。根据DF浓度无法预测赖氨酸的AID（P > 0.05）。总之，阿拉伯木聚糖和NSP木糖残基是最能解释因DF浓度导致变异的DF成分，除赖氨酸的AID外，可用于预测玉米副产品中能量和DF的消化率以及DE和ME值。
