钙和维生素D对生长肉鸡免疫及抗氧化功能的影响

Effects of Calcium and Vitamin D on Immune and Antioxidant Functions in Growing Broilers

本试验旨在研究日粮中钙(Ca)和维生素D水平对生长肉鸡免疫及抗氧化功能的影响。采用2×2完全随机试验设计,选用体重相近的4周龄爱拔益加(AA)肉鸡144只,随机分成4个处理,每个处理6个重复,每个重复6只鸡,分别饲喂含Ca0.90%、1.15%和维生素D750、5000IU/kg的试验日粮,试验期为4周。结果表明,1)维生素D对胸腺和脾脏指数作用显著(P<0.05),随维生素D添加量的增加免疫功能增强;与0.90%Ca组相比,1.15%Ca组可降低法氏囊指数(P<0.05)和血清免疫球蛋白含量(P>0.05);维生素D和Ca的互作显著影响脾脏指数和血清白介素-2(IL-2)(P<0.05),5000IU/kg维生素D+0.90%Ca组脾脏指数和IL-2较高;2)随维生素D添加量的增加,血清和肝脏总超氧化物歧化酶(T-SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、总抗氧化能力(T-AOC)升高,丙二醛(MDA)含量降低;随Ca添加量的增加,生长肉鸡的抗氧化性能降低,且对机体肝脏T-SOD、GSH-Px、T-AOC影响显著(P<0.05);维生素D和Ca的互作对血清和肝脏T-SOD、GSH-Px、MDA影响显著(P<0.05),5000IU/kg维生素D+0.90%Ca组在抗氧化方面优势明显。综合分析,5000IU/kg维生素D+0.90%Ca组在抗氧化和免疫方面具有一定的优势。因此,实际生产中在满足生长肉鸡Ca基本需要量的同时,适当增加维生素D添加量对提高生长肉鸡免疫和抗氧化功能具有重要的作用。

The experiment was designed to evaluate the effects of calcium and vitamin D on immune and antioxidant functions in growing broilers. A 2×2 completely random design was used in the experiment. One hundred and forty-four 4-weeks-old AA growing broilers with the close body weight were divided into 4 treatments with 6 replicates in each treatment and 8 broilers in each replicate. The broilers were fed the diets with 0.90%,1.15% calcium and 750,5 000 IU/kg vitamin D,respectively. The results showed as follows： 1） vitamin D had significant effects on thymus and spleen indices （P〈0.05）,and with the increase of vitamin D levels,the immunity was enhanced; compared with 0.90% calcium,1.15% calcium decreased the bursa of Fabricius index （P〈0.05） and the concentration of serum immunoglobulin （P〈0.05）; there was interaction between vitamin D and calcium on spleen index and IL-2 （P〈0.05）; higher spleen index and IL-2 concentration were obtained from the 5 000 IU/kg vitamin D＋0.90% calcium group; 2） with the increase of vitamin D levels,the T-AOC and the activities of T-SOD and GSH-Px in serum and liver were increased,and the content of MDA was decreased; but with the increase of calcium levels,the antioxidant capacity of broilers was weakened,and calcium had significant effects on the T-AOC and the activities of T-SOD and GSH-Px in liver （P〈0.05）; the interaction of vitamin D and calcium had significant effects on the activities of T-SOD and GSH-Px and the content of MDA in serum and liver （P〈0.05）; 5 000 IU/kg vitamin D＋0.90% calcium group had more obvious superiority in antioxidant capacity than other groups. In conclusion,the 5 000 IU/kg vitamin D＋0.90% calcium group had the certain superiority in enhancing the immunity and antioxidant capacity. Therefore,in practice,adding the basal level of calcium and more vitamin D than the basal requirement at the same time had important effects on enhancing immune and antioxidant functions in growing broilers.