不同锌源及水平对生长肥育猪血清酶活性和组织器官锌沉积量的影响

Effects of Different Zinc Sources and Levels on Serum Enzyme Activities, Tissue and Organ Zinc Accumulations of Growing-Finishing Pigs

本试验旨在研究不同锌源[蛋氨酸锌(Zn-Met)或硫酸锌(ZnSO_4)]及水平对生长肥育猪血清酶活性和组织器官锌沉积量的影响。选用体重[(33.70±2.76)kg]相近的"杜×长×大"生长肥育猪32头,随机分成4组,每组8个重复,每个重复1头猪。对照组饲喂基础饲粮,试验组在基础饲粮中分别添加40 mg/kg Zn-Met、40 mg/kg ZnSO_4和80 mg/kg ZnSO_4(以锌元素计)。预试期7 d,正试期72 d,分30~60 kg和61~90 kg 2个阶段。结果表明:1)与对照组相比,饲粮添加40 mg/kg Zn-Met显著降低了生长肥育猪血清谷丙转氨酶(ALT)、谷草转氨酶(AST)和乳酸脱氢酶(LDH)活性(P<0.05),显著提高了血清碱性磷酸酶(ALP)活性(P<0.05);饲粮添加40 mg/kg ZnSO_4显著降低了血清ALT和LDH活性(P<0.05);饲粮添加80 mg/kg ZnSO_4显著降低了血清ALT活性(P<0.05),显著提高了血清ALP活性(P<0.05)。40 mg/kg Zn-Met组生长肥育猪血清ALT、AST和LDH活性最低,血清ALP活性最高。2)与对照组相比,饲粮添加40 mg/kg Zn-Met显著提高了生长肥育猪血清锌含量(P<0.05),40 mg/kg Zn-Met组血清锌含量最高。3)与对照组相比,饲粮添加40 mg/kg Zn-Met或40、80 mg/kg ZnSO_4对生长肥育猪脾脏、胰脏、毛和肌肉锌沉积量均无显著影响(P>0.05),但显著提高了肝脏和骨锌沉积量(P<0.05)。综上所述,饲粮添加40 mg/kg Zn-Met或40、80 mg/kg ZnSO_4可改善生长肥育猪血清酶活性、血清锌含量及肝脏和骨锌沉积量。本试验条件下,生长肥育猪饲粮添加40 mg/kg Zn-Met为宜。

This trial was conducted to evaluate the effects of different zinc sources[zinc methionine(Zn-Met)or zinc sulfate(ZnSO 4)]and levels on serum enzyme activities,tissue and organ zinc accumulations of growing-finishing pigs.Thirty-two growing-finishing pigs(Duroc×Landrace×Large White)with similar body weight[(33.70±2.76)kg]were randomly divided into 4 groups with 8 replicates per group and 1 pig per replicate.The control group was fed a basal diet,while experimental groups were fed the basal diets supplemented with 40 mg/kg Zn-Met,40 mg/kg ZnSO 4 and 80 mg/kg ZnSO 4(calculate by zinc),respectively.There was a 7-day adaptation period and a 72-day experimental period.In addition,the experimental period was divided into two periods of 30 to 60 kg and 61 to 90 kg.The results showed as follows:1)compared with the control group,dietary supplementation with 40 mg/kg Zn-Met significantly decreased the activities of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and lactate dehydrogenase(LDH)in serum of growing-finishing pigs(P<0.05),significantly increased the serum alkaline phosphatase(ALP)activity(P<0.05);dietary supplementation with 40 mg/kg ZnSO 4 significantly decreased the activities of ALT and LDH in serum(P<0.05);dietary supplemented with 80 mg/kg ZnSO 4 significantly decreased the serum ALT activity(P<0.05),significantly increased the serum ALP activity(P<0.05).Besides,40 mg/kg Zn-Met group got the lowest activities of ALT,AST and LDH in serum,and the highest serum ALP activity.2)Compared with the control group,dietary supplementation with 40 mg/kg Zn-Met significantly increased serum zinc content of growing-finishing pigs(P<0.05),and 40 mg/kg Zn-Met group got the highest serum zinc content.3)Compared with the control group,dietary supplementation with 40 mg/kg Zn-Met or 40 and 80 mg/kg ZnSO 4 had no significant effects on the accumulations of zinc in spleen,pancreas,hair and muscle of growing-finishing pigs(P>0.05),while significantly increased the accumulations of zinc in liver and bone(P<0.05).In conclusion,dietary supplementation with 40 mg/kg Zn-Met or 40 and 80 mg/kg ZnSO 4 can improve the serum enzyme activities,serum zinc content and accumulations of zinc in liver and bone of growing-finishing pigs.Under the condition of this experiment,the suitable dietary Zn-Met supplemental level is 40 mg/kg for growing-finishing pigs.