裹包贮存对全混合日粮品质的影响

Effect of baling storage on quality of total mixed ration

为使中小规模奶牛养殖场和个体养殖户也能用到全混合日粮(Total Mixed Ration,TMR),研究用拉伸膜将制成的TMR饲料成品进行裹包后存放的效果。TMR饲料初始含水率分别调整为40%、50%和60%,利用裹包技术将新鲜制作的TMR饲料进行打捆裹包,分别于存放后的第0、3、7、15和30d后进行感官评定、营养物质含量和发酵指标的测定。试验结果表明:各处理TMR饲料裹包存放15d以内其感官品质表现良好,存放30d时表层有发霉现象产生;随着贮存时间的延长,TMR饲料中的营养物质含量会由于贮存过程中干物质的损失而有相应的增加;裹包TMR饲料的pH值随存放时间延长表现为显著降低(P<0.05),50%初始含水率表现最低的pH值(P<0.05),氨态氮含量则表现为显著增加(P<0.05),且初始含水率越高,氨态氮生成量越高(P<0.05)。综合生产、品质和适口性等各方面认为50%含水率为裹包TMR较为适宜的水分含量。因此,裹包技术可以应用于TMR的有效贮存以实现TMR饲养技术在中小规模养殖场和个体养殖户中的应用。

In order to make small-scale and individual dairy cattle farms total mixed ration （TMR）, research was made to study the storage effects after TMR was baled. Moisture contents of TMR were adjusted to 40%, 50%, and 60%, respectively. Fresh TMR were wrapped and baled using stretch film. After 0, 3, 7, 15, and 30 days of storage, sensory evaluation was carried out, and nutrient contents and fermentation qualities were determined. The results showed that the sensory characters were well kept during first 15 days of storage, while mold occurred on the outer surface after 30 days. Along with the storage time, the nutrient contents increased compared with fresh TMR owing to the dry matter losses during storage. The pH value of baled TMR decreased significantly （P〈O.05） along with the proceeding of storage and the TMR with 50% of moisture content had the lowest pH value. The NH3-N content of TMR increased significantly （P〈0.05） during storage. And the higher the moisture content was, the higher the NH3-N concentration was. 50% of moisture content was considered to be the preferred selection for baled TMR from the aspects of production, quality and palatability. These results indicate that baling technology can be used to achieve the effective storage of TMR. The small-scale and individual farms can use TMR diets.