肉仔鸡能量营养需要的研究——Ⅱ、肉仔鸡前期日粮能量浓度对后期增重及饲料利用效率的影响

用饲养试验法研究了前期日粮能量浓度对后期肉仔鸡生长强度、累积增重、饲料利用效率的影响。由前期(0～28日龄)给饲不同能量浓度日粮(AME,Mcal/kg,Ⅰ—2.50,Ⅱ—2.70、Ⅲ—2.89、Ⅳ—3.10、Ⅴ—3.25、Ⅵ—3.35)的六个试验组,分别随机选择Arbot Acres品种商品代28日龄公、母混合肉仔鸡84只,等分6个重复组,每组试鸡14只,共计504只。以重复组为单位笼养、群饲、测试有关数据。各处理组鸡笼均匀配市于半封闭式鸡舍的不同部位.上述各组试鸡,于后期(29～56日龄)换饲能量浓度为3.14的同一日粮。试验测得,前期日粮能量浓度越低,后期生长强度越高(%,第Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ组分别为215.7、188.0、170.8、168.7、155.5.147.2)、累积增重越大(克,第Ⅰ—Ⅵ组分别为1467.3、1437.6、1379.7,1422.5、1368.8、1368.7)、每公斤增重的AME消耗量(Kcal,第Ⅰ—Ⅵ组分别为7341、7548、7882.7922、8042、8130)和耗料量(公斤,第Ⅰ—Ⅵ组分别为2.34、2.40、2.51、2 54、2.56、2.59)越低,明显地表现出肉仔鸡在后期日粮能量浓度提高以后,对前期生长的补偿作用.据各项测值综合分析,肉仔鸡前、后期日粮能量浓度分别为“3.10～3.25(前)和3.14(后)”时最佳,此时56日龄仔鸡体重为2265.5～2249.1克,每公斤增重耗料2.22～2.18公斤、耗AME6955～6854 Kcal,0～56日龄累积耗料4930.1～4824.5克/只。受饲料条件限制,难以配制高能量浓度平衡日粮时,采用能量浓度为“2.7～2.9(前期)、3.1(后期)”的能量浓度组合方案,亦可取得同上述最佳能量浓度组合方案相近的56日龄体重(2202.4～2187.3克)和耗料比(2.25～2.26公斤/公斤);此时前期日粮的麸皮用量高达14～25%。添加油脂饲料高达6%,可有效地提高日粮能量浓度,并获得理想的生产水平,就实际应用而言,它取决于由其赢得的经济效益是否能抵补得上提高了的饲料费用。

STUDIES ON THE ENERGY REQUIREMENES OF BROILER Ⅱ.Effects of energy concentration of broiler’s earlier stage ration on weight-gain and feed utilization rate of later stage

The effects of energy concentration of the ration of broiler's earlier stage (0-28 days) on its later stage growth intensity, accumulated weight gain and feed utilization rate was studied by feeding experiments. It is shown that the lower the energy concentration of ration in earlier stage, the higher the growth intensity of later stage (%, the fingues of 1, 2, 3, 4, 5, 6, groups are 215.7, 1888.0, 170.8, 168.7, 155.5, 147.2), the higher the accumulated weight gain (g, the finguers of the groups are 1467.3, 1437.6, 1379.7, 1422.5, 1368.8, 1368.7), the lower the AME consuming per kg weightgain (K cal, the fingues are 7341, 7548,7882,7922, 8042, 8130) and the lower the feed consumption (kg, the fingues are 2.34, 2.40,2.51, 2.54, 2.56, 2.59). According to above, the results are very obvious to show that after raising energy concentration of later stage ration there is a compesated effect on earlier stage growth. To analyse all the testing value, The best energy concentration of broiler's earlier and later stages ration are respec- tively 3.10-3.25 (earlier) and 3.14 (later). In this case,the weight of 56 days broiler is 2265.5-2249.1g, the feed consumption of gain in weight per kg is 2.22-2.18 kg, A ME consumption is 6995-6854 K cal, accumulated feed consumption of 0-56 days is 4930.1-4824.5g each. When the high energy concentration balance ration is difficut to prepare because of limitation of feed conditions, the combination plan of energy concentration of 2.7-2.9 (earlier stage) and 3.1 (later stage) is usefal for getting the similar results as above state, the weight on 56 days is 2202.4-2187.3g, and the F/G is 2.25-2.26 kg.