热喷麦秸营养补添效果的研究

THE RESPONSE OF SHEEP GIVEN HEAT—EXTRUDED AND UNTREATED WHEAT STRAW BASED DIETS TO SUPPLEMENTARY FEEDING

选用装配瘤胃和十二指肠瘘管的成年杂种羯羊九只,分三组进行试验:1.热喷麦秸组:该组试羊除每日每只给饲400克基础混合精料外,自由采食热喷麦秸,2.热喷麦秸营养补添组:该组试羊饲喂方式基本上和热喷麦秸组相似,所不同的是除基础混合精料和热喷麦秸外,每日每只试羊另外补饲50克鱼粉和0.75千克青草;3.非热喷组:该组试羊每日每只除给饲400克基础混合精料外,另外自由采食未经热喷处理的麦秸。所用的基础混合精料的组成(%)为:玉米60.0;麸皮22.5;大豆饼15.0和混合矿物质2.5。试验总共进行118天。试验期间除观察羊毛生长和增重指标外,主要是对各组试羊的瘤胃微生态环境进行了检测。检测指标包括有瘤胃内48小时干物质消失率;粗蛋白降解率;瘤胃液的 PH 值,氨 N 水平和挥发性脂肪酸(VFA)的数量和比例;瘤胃食糜的 N/S 比;微生物蛋白产量;瘤胃和十二指肠食糜流通量;进入十二指肠的氨基酸数量以及采食量等多项指标。试验结果表明,热喷麦秸补添鱼粉和青饲后,降低了瘤胃内乙酸的比例,提高了丙酸的比例,NGR 指标也趋于改善;瘤胃和十二指肠食糜流通量增加;进入小肠的氨基酸数量增多;采食量明显提高;同时羊毛生长和增重指标也要比其他两组高。

The effects of fish meal and green forage supplemcntation on the rumen fermentation and performance of sheep were examined in an expariment with crossbred sheep(LBW 30 kg)fitted with a tureen and duodenal cannu- la.The sheep were divided into 3 groups,i.e.(1)HEWS—Ⅰ group.All sheep were fed with 400g concentrate mixture and only heat—extruded wheat straw ad lib;(2)HEWS—Ⅱ group.The animals were fed the same as HEWS—Ⅰ except for 50g fish meal and 0.75 kg fresh forage being sup— plemented,(3)control group.Fed 400g of the concentrate mixture and untreated wheat straw ad lib.The composition of the concentrate mixture was(%): corn 60.0,wheat bran 22.5,soybean meal 15.0 and mineral mix 2.5.The trial lasted 118 days.During the experimental period,wool growth,weight gains as well as parameters of tureen enviromental conditions were measured.The results showed that the supplementation to heat extruded wheat straw with fish meal and fresh forage decreased the proportion of acetate and increased that of propionate,in consequence,resulted in a lowe NGR.It was also found that the supplementation caused higher digest flows through the tumen and duodenum and amount of amino acids entering the small intestine,and th- at intakes of DM and wheat straw and wool growth and daily weight gains of the sheep in HEWS—Ⅱ group were much higher than those in other two groups.