13～18周龄笼养蛋鸭适宜蛋白质和蛋氨酸水平的研究

用 32 4羽满 1 2周龄的金定鸭 ,通过饲养试验、代谢试验、屠宰试验和对试鸭产蛋期 (1 9～ 2 8周龄 )产蛋性能的观察 ,研究了在等能条件下(ME :1 1 51MJ/kg) ,不同蛋白质水平 (CP :1 3 %、 1 5 %、 1 7% )和蛋氨酸水平 (Met/CP :0 0 1 7、 0 0 2 2、 0 0 2 7)组成的 9种饲粮对 1 3～ 1 8周龄笼养蛋鸭的生长性能、养分利用、体成分沉积和产蛋期产蛋性能的影响。结果表明 :该阶段饲粮粗蛋白、蛋氨酸水平对体增重影响不显著 (P >0 0 5) ;体增重与蛋氨酸 (% )呈一定的正相关 (r=0 4574) ;CP为 1 3%、Met/CP为 0 0 2 7组采食量一直较稳定、较高 ,且饲料效率又好。代谢试验 :不同粗蛋白、蛋氨酸水平饲粮对试鸭氮存留率和能量的利用率影响显著(P <0 0 5或P<0 0 1 ) ,且它们随饲粮CP水平的升高而降低 ,随蛋氨酸水平升高而升高 ;磷的利用率也分别以CP为 1 3%的水平和Met/CP为 0 0 2 7的水平极显著地高于其他水平对磷利用率 (P <0 0 1 )。屠宰试验 :当Met/CP为 0 0 2 7时 ,体氮沉积量和体磷沉积量最佳。产蛋性能 :开产日龄和高峰日龄与 1 3～ 1 8周龄CP食入量呈弱的负相关 (r=- 0 1 83 3和r=- 0 0 984) ,与蛋氨酸食入量呈正相关 (r =0 5780和r =0 435 0 )。饲粮粗蛋白、蛋氨酸水平对 1 9～ 2 8周龄

Optimum dietary protein and methionine levels for cage-rearing laying ducks in 13～18 weeks'period

A grouped feeding,metabolism and slaughter trials for laying ducks in 13～18 weeks'period were conducted to determine the effect of nine isoenergetic diets(ME:11 51 MJ/kg)with different crude protein(CP)levels(CP:13%,15%,17%)and methionine(Met)levels(Met/CP:0 017,0 022,0 027)on the growth,utilization of nutrients and body deposit.In the 19th week,three ducks were chosen randomly in per repeat of the per group and the nine ducks of three repeats of the primary group formed one homologous group,and there were nine groups in all.All ducks were fed with the same laying diets from 19 to 28 weeks.The results were as follows:No significant differences(P>0 05)were found in body weight gain from 13 to 18 weeks and there was a positive correlation(r=0 457 4)between body weight gain and dietary Met levels.When CP was 13% and Met/CP was 0 027,the feed intake and feed conversion ratio of the group 3 were better than those of other groups.The different dietary CP and Met levels had significant or great significant effect(P<0 05 or P<0 01)on nitrogen retention ratio,utilization of energy(E) decreased as dietary CP levels rose and increased as dietary Met levels rose.The utilization of phosphorus(P)was also great significantly higher than that of others when CP was 13% and Met/CP was 0 027.The deposits of nitrogen and P were the best when Met/CP was 0 027 among the groups.From 19 to 28 weeks,there was a positive correlation(r=0 578 0 and r=0 435 0)between the day of the laying ratio from 50% to 80% and dietary Met intake in 13～18 weeks.There was no significant difference(P>0 05)among average egg weights and laying ratios in different groups from 19 to 28 weeks.The average laying raio decreased as dietary CP levels rose from 19 to 28 weeks.13% CP,and 0 027 Met/CP in diets containing ME=11 51 MJ/kg were suitable for cage rearing laying ducks in 13～18 weeks period.