赖氨酸占蛋白质及饲粮的比例对杜洛克猪生长肥育性能及胴体品质的影响

杜洛克猪48头,体重27kg左右,分6组。试验前期(27～60kg)日粮的消化能均为13.67MJ)/kg,后期(60～90kg)均为13.44MJ/kg。粗蛋白1、2、3组前期均为18％,后期均为16％;4、5、6组前期均为16％,后期均为14％。同时配合3种赖蛋比水平6.6～6.9％,6.1～6.25％及5％。试验结果表明:4、5、6组平均日增重、饲料利用率及胴体瘦肉率都略高于1、2、3组,但差异不显著(P>0.05)。在前期,以第5组平均日增重最高(达782克),极显著高于其他各组(P<0.01);饲料利用率2.41,极显著好于其他各组(P<0.01)。后期以第5组平均日增重最高(875克)。试验前期,第5组获得最佳的日增重(822克),极显著高于其他各组(P<0.01),饲料利用率2.98,胴体瘦肉率65.79％,与其他各组差异不显著(P>0.05)。在两种粗蛋白水平组内,均以赖蛋比6.1～6.25％的第5组和第2组生长速度最快(822克和778克)。说明在相同的能量水平下,赖蛋比是影响生长速度的主要因素。

Effect of Levels of Lysine in Diet on the Performance of Duroc Pig

Forty eight Duroc pig with an average weight of 27 kg were allocated into 6 treatments. The di-gestable energy in diet was 13. 6 MJ/kg for the first period of treatment(27-60kg)and 13. 44 MJ/kg for the second (60-90kg). For treatments 1,2 and 3 the levels of lysine(%) in the first period were 1.2,1. 1 and 0. 9 and in the second period were 1.1, 1.0 and 0. 8. For treatments 4,5 and 6 were 1.1, 1. 0 and 0. 8 in the first period and 0. 95,0. 87 0. 70 in the second. The levels of crude protein in two periods were 18% and 16 % for treatments 1,2 and 3, and 16 % and 14 % for treatments 4 ,5 and 6, Results showed that the average weight gain, feed conversion and carcass lean ratio in treatments 1,2 and 3 were slightly higher than those in treatments 4,5 and 6(P>0. 05). In the first period,the fifth group had the highest daily live weight gain ( 78 2g) and the lowest feed conversion ratio (2. 41:1) , which were significantly different from those in any other groups(P<0. 01). It also showed the highest daily liveweight again (875g)ln the second period, The daily liveweight gain of the fifth group in the whole period was 822g/d, which was significantly higher than that of any other group(P<0. 01). The feed coversion ratio and carcass lean ratio were 0. 98 : 1 and 65% for the fifth group,which did not differ significantly from other groups (P>0. 05), In all groups fed of the same crude protien level with different proportion of lysine io protein, the fifth and the second group with the 6. 25-6.1 % proportion of lysine to protein,had fastest growth rate(822 and 788g/d).