饲粮中锰(Mn)的缺乏与过量对肉仔鸡性能的长期影响

用1日龄AA肉用雏鸡120只(公母各半),分成3组,分别喂以含Mn 16ppm(缺Mn组)的玉米-豆饼型基础饲粮和含Mn 120ppm(对照组)及2840 ppm(Mn过量组)的补Mn饲粮8周。结果表明,与对照组比较,实用饲粮Mn缺乏降低鸡的体增重(P>0.05)和跖骨灰、肝、胰、心、脾、胆汁(P<0.01)及肌肉(P>0.05)中的Mn含量与心组织含Mn超氧化歧化酶(MnSOD)活性(P<0.01),显著提高腿病发生率和心含CuZn超氧化歧化酶(CuZnSOD)活性(P<0.01),单位增重的耗料量(F/G)有增加趋势(P>0.05);Mn过量降低鸡采食量和体增重(P<0.01),提高上述组织和胆汁中的Mn含量(P<0.01),单位增重的耗料量(F/G)也有增加趋势(P>0.05),而对腿病发生率与心MnSOD及CuZnSOD活性无进一步影响(P>0.05)。

The Long-Term Effects of Manganese (Mn) Deficiency and Excess in a practical Diet on Performances of Broiler Chicks

120 day-old Arbor Acres (AA) broiler (1/2公, 1/2母) were randomly allotted to three groups which were fed either a basal corn-soybean meal diet Containing 17ppm Mn (Mn-deficient group) or Mn-supplemented (reagent grade MnS04·H20) diets containing 120ppm Mn (control group) and 2840ppm Mn (Mn-excessive group) in cages for 8 weeks. The results indicated that compared to the control group, Mn deficiency reduced bodyweight gain (P>0.05) of the chicks and Mn contents of metatarsal bone ash, liver, pancreas, heart, spleen, bile (p<0.01) and muscle (P>0.05)and MnSOD activity (P<0.01) of heart, and increased an incidence of leg abnormality and CuZnSOD activity of heart(P<0.01)and feed intake per unit gain (F/G) (P>0.05). Mn excess decreased feed intake and bodyweight gain (P<0.01), and raised Mn contents (P<0.01) of the above mentioned tissues and tile and also feed intake per unit gain (P>0.05) , and had no further effects (P>0.05) on an incidence of leg abnormality and heart MnSOD and CuZnSOD activities (P>0.05) .