饲粮铜和维生素A及其互作效应对肉仔鸡生长性能及抗氧化功能的影响

本研究旨在探讨铜和维生素A及其互作效应对内仔鸡生长性能及抗氧化功能的影响.试验选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每个重复14只鸡.采用4×2(铜×维生素A)完全随机设计,饲粮铜的添加量分别为0、8、150、225 mg/kg,维生素A的添加量分别为1 500、5 000 IU/kg,分为2个生长阶段,前期为1～4周龄,后期为5～7周龄.结果表明:1)高铜( 150、225mg/kg)抑制了全期肉仔鸡生长性能,提高了全期血清铜蓝蛋白(Cp)和后期血清总超氧化物歧化酶(T-SOD)活性(P＜0.05).2)5 000 IU/kg维生素A组获得较好的生长性能,提高了全期血清T-SOD活性,降低了前期血清Cp活性(P＜0.05).3)铜和维生素A互作效应对前期体增重、血清Cp和T-SOD活性及全期料重比有显著影响(P＜0.05),且二者间存在互补作用.铜(8 mg/kg)×维生素A(5 000 IU/kg)组与铜(0 mg/kg)×维生素A(5 000 IU/kg)组对前期肉仔鸡获得良好生长性能和提高血清T-SOD活性均有促进作用,但对血清Cp活性有显著降低作用(P＜0.05).由此可见,在基础饲粮铜水平为16～23mg/kg时,铜的适宜添加量为前期8 mg/kg,后期0～8 mg/kg；全期维生素A的适宜添加量为5 000 IU/kg.

Effects of Dietary Copper and Vitamin A and Their Interaction on Growth Performance and Antioxidant Function in Broilers

The experiment was conducted to investigate the effects of different dietary copper and vitamin A levels and their interaction on growth performance and antioxidant function in broilers.Four hundred and forty-eight one-day-old Avian broilers were randomly allotted to eight groups with four replicates in each group and fourteen broilers in each replicate.A 4×2(Cu×vitamin A) factorial arrangement design was used in this experiment,and dietary copper levels were 0,8,150 and 225 mg/kg,respectively;vitamin A levels were 1 500 and 5 000 mg/kg,respectively.The experiment included two periods,early stage was 1 to 4 weeks and later stage was 5 to 7 weeks.The results showed as follows: 1) dietary high copper levels(150 and 225 mg/kg) restrained the growth performance in the whole period,and significantly increased the serum ceruloplasmin(Cp) activity in the whole period and total superoxide dismutase(T-SOD) activity from 5 to 7 weeks(P<0.05).2) The 5 000 IU/kg vitamin A group got a better growth performance and significantly increased the serum T-SOD activity in the whole period(P<0.05),but significantly decreased Cp activity from 1 to 4 weeks(P<0.05).3) The interaction between Cu and vitamin A significantly affected the body weight gain,serum Cp and T-SOD activities from 1 to 4 weeks and feed/gain in the whole period(P<0.05),and they had a complementary effect.Groups Cu(8 mg/kg)×vitamin A(5 000 IU/kg) and Cu(0 mg/kg)×vitamin A(5 000 IU/kg) had facilitation effects in both growth performance and serum T-SOD activity of broilers,but significantly decreased serum Cp activity(P<0.05).In conclusion,when dietary copper level in basal diets is 16 to 23 mg/kg,dietary appropriate copper supplemental level is 8 mg/kg from 1 to 4 weeks,and 0 to 8 mg/kg from 5 to 7 weeks,and appropriate vitamin A supplemental level is 5 000 IU/kg in the whole period.