Studies on the Improvement of Feeding Value of Structural Carbohydrate in Wood by Explosion Treatment

木材含有大量的结构碳水化合物，可能被反刍动物消化。然而，纤维素和木质素之间的强结合通常阻碍了其作为饲料的利用。也就是说，木材的木质化是降低木材消化率的主要因素。爆炸处理是脱木质素的有效方法之一，因为这种处理可以很容易地切断木质素和碳水化合物的键。此外，木质素在爆炸过程中有时会产生酚类单体。这种材料在一般饲料中是找不到的。因此，在实际用于动物之前，必须研究这种材料对消化率和瘤胃发酵的影响。本试验研究了爆炸处理对爆炸木材营养价值的影响，并探讨了爆炸木材作为饲料的可能用途。细胞壁组分受到爆炸的冲击，半纤维素含量降低，可溶性木质素含量增加。其他的成分变化很小。爆炸样品水提物中检出乙酸、糠醛和单糖。爆炸处理对杨树和白桦的影响显著。炸杨树和白桦树的体内消化率分别为42%和36%。在体外实验中，添加meoh提取物降低了淀粉和纤维素的消化。在酪蛋白中添加MeOH对氨的生成没有明显的影响。MeOH提取物的主要成分为降解木质素，分子量为1700 ~ 1900。降解木质素处理可抑制瘤胃微生物的比活性。然而，由于体内实验表明，在绵羊体内饲喂爆炸木对VFA的产量没有影响，因此爆炸木可以作为反刍动物的饲料成分之一。

Wood contains a large amount of structural carbohydrate which can potentially be digested by ruminants. However, strong bond between cellulose and lignin usually prohibits its utilization as feed. That is, lignification in wood is a main factor in lowering digestibility of it. Explosion is known to be one of the effective way for delignification, since the lignin and carbohydrate bond can easily cleaved by this treatment. In addition, phenolic monomers are sometimes produced from lignin during explosion process. This material is not found in usual feed. Therefore, the effect of this material on digestibility and rumen fermentation has to be investigated prior to the practical use of exploded wood for animals. In this experimant, effect of explosion treatmtnt on nutritive value and possible usage of exploded wood as feed are investigated. The cell wall component was subject to umpact by the explosion, with decrease of hemicellulose content and increase of soluble lignin. The other compositions varied very little. Acetic acid, furfural and monosaccharides were detected in water extract of exploded samples. The explosion treatment had remarkable impact on poplar and white birch. Exploded poplar and white birch gave 42 and 36 percent in vivo digestibilities after the treatment. Addition of meoh extract resulted decrease of starch and cellulose digestion in the in vitro experiment. MeOH addition to casein did not have a clear effect on ammonia production. Major component of MeOH extract was degraded lignin, 1700-1900 of molecular weight. Degraded lignin by the treatment might inhibit specific activity of rumen microorganisms. However, since in vivo experiment showed that VFA production was not influenced by feeding exploded wood in sheep, exploded wood can practically be utilized as one of the feed ingredients for ruminants.