Ju Ye Ri, Baek Youl Chang, Jang Sun Sik, Oh Young Kyoon, Lee Sung Suk, Kim Yong Sik, Park Keun Kyu
Cargill Agri Purina, Inc. Gunsan Plant, Gunsan 54007, Korea.
National Institute of Animal Science, Rural Development Administration, Wanju55365, Korea.
Asian-Australas J Anim Sci. 2020 Jun;33(6):930-940. doi: 10.5713/ajas.19.0658. Epub 2019 Dec 24.
This study was conducted to evaluate changes in nutritional value and in situ dry matter (DM) degradability of oak and pine wood before and after steam-digestion process (60 min/160°C/6 atm) and feeding effect of the oak roughage on performance and behavior of Hanwoo steers.
Chemical composition and tannin concentration were analyzed for oak and pine trees before and after the pretreatment. In situ DM and effective degradability of these samples were assessed using a nylon bag method. In vivo trial was performed to estimate animal performance and behavior, using steers fed total mixed ration (TMR) diets containing 0% (control), 25% (OR-25), and 50% (OR-50) of the oak roughage. Eighteen steers were allocated into nine pens (2 steers/pen, 3 pens/treatment) for 52 days according to body weight (BW) and age.
By the steam-digestion treatment, the neutral detergent-insoluble fiber was decreased from 86.5% to 71.5% for oak and from 92.4% to 80.5% for pine, thereby increasing non-fiber carbohydrate. In situ DM degradability of treated oak reached 38% at 72 h, whereas that of untreated oak was only 11.9%. The 0 h degradability of the treated pine increased from 5.9% to 12.1%, but the degradability was unchanged thereafter. Animal performance including BW, average daily gain, DM intake, and feed conversion ratio was not different among control and oak treatments. No differences were detected in animal behavior such as lying, standing, rumination, drinking, and eating, except walking. Walking was higher in control than oak treatments with numerically higher eating and lower lying times, probably due to bulkier characteristics of rice straw in the diet.
This study demonstrates that the oak roughage can be substituted for 50% of total forage or 100% of rice straw in TMR diets at early fattening stage of Hanwoo steers.
本研究旨在评估蒸汽消化处理（60分钟/160°C/6个大气压）前后橡木和松木的营养价值及原位干物质（DM）降解率，以及橡木粗饲料对韩牛育肥牛生长性能和行为的饲喂效果。
分析预处理前后橡木和松木的化学成分及单宁浓度。采用尼龙袋法评估这些样品的原位DM和有效降解率。进行体内试验，以含0%（对照）、25%（OR - 25）和50%（OR - 50）橡木粗饲料的全混合日粮（TMR）饲喂育肥牛，估计动物的生长性能和行为。根据体重（BW）和年龄，将18头育肥牛分配到9个栏中（每栏2头，每个处理3栏），为期52天。
通过蒸汽消化处理，橡木的中性洗涤不溶性纤维从86.5%降至71.5%，松木从92.4%降至80.5%，从而增加了非纤维碳水化合物。处理后的橡木在72小时时原位DM降解率达到38%，而未处理的橡木仅为11.9%。处理后的松木0小时降解率从5.9%提高到12.1%，但此后降解率未变。对照和橡木处理组之间，包括BW、平均日增重、DM摄入量和饲料转化率在内的动物生长性能没有差异。除行走外，在躺卧、站立、反刍、饮水和采食等动物行为方面未检测到差异。对照处理组的行走次数高于橡木处理组，采食次数在数值上更高，躺卧时间更低，这可能是由于日粮中稻草体积较大的特性所致。
本研究表明，在韩牛育肥牛的早期育肥阶段，橡木粗饲料可替代TMR日粮中50%的总粗饲料或100%的稻草。
