【摘要】 选用２５～５０周龄的豫州褐蛋鸡，分成４组试验，分别饲喂含粗蛋白质为１６．６９％和１８．６０％各２组水平相同的４组不同日粮配方。２４周试验的结果表明，采用粗蛋白质１６．６９％的全价Ⅱ号日粮配方，比１８．６５％和１８．５２％的Ⅲ、Ⅳ号配方组的各项指标高，平均每只鸡产蛋量分别为１４０．１５个、１３４．１０个、１３３．５７个；产蛋率８０％以上持续时间是１７，１５，１４周；料蛋比为２．１８和２３３；受精蛋孵化率为９１．０３％，８９．３５％，８９．８９％。结果还表明，过高粗蛋白质日粮不仅是浪费，反而会增加生理内耗负担。更多还原

【Abstract】 25～50week-old Yuzhou Browns were selected and divided into 4 experimentalgroups and 4 different diets ,of which 2 diets were with 16. 69%of crude protein,while theother 2 diets were 18. 60%. Experiment for 24 weeks showed that every indea from diet Ⅱwith 16. 69%of crude protein was higherthan that from diet Ⅲ or Ⅳ with 18. 65%and18. 52%of crude protein. As to the 3 diets,the number of eggs laid by per hen were respec-tively 140. 15,134.1 and 133. 57,the time for egg-laying rate reaching over 80%lasted 17weeks,15 weeks and 14 weeks,the feed conversion ratios were 2. 18 and 2. 33,and the fer-tile egg hatchabilities were 91. 03%, 89. 35%and 89. 90%. The results also showed thattoo high a level of crude protein was not only a waste but also a physiological burden tolaying hens.更多还原