The Influence Of Various Dietary Copper And Vitamin A Levels On Performance And Physico-Chemical Parameters In Broilers

A 4×2(Cu× VA) experiment with repeats was designed to investigate the influence of various dietary Cu and vitamin A levels on performance, immunology competence , serum CuZn-SOD activity and insulin concentration in broilers. Results showed that dietary copper levels(8 mg/kg)significantly increased with performance, antibody valence to NDV in serum and CuZn-SOD activity at the early stage , ANAE+% of lymphocyte and ether extract apparent deposit rate through the whole period (P<0.01) ; Copper(0 mg/kg) group significantly reduced feed : gain ratio at the later stage and increased with insulin concentration of serum through the whole period (P<0.01 ) ; Group with Cu(150 mg/kg) significantly increased with crude protein apparent deposit rate (P<0.01 ) . Dietary high copper levels(150 and 225 mg/kg diet) suppressed performance , immune function , CuZn-SOD activation , insulin concentration and ether extract apparent retaining rate significantly through the whole period . From 0 to 4 weeks , dietary Cu supplemental level was 8mg/kg diet , and from 5 to 7weeks was 0-8 mg/kg diet. Supplementation with 5000IU/kg vitamin A significantly improved performance and CuZn-SOD activity at the early stage , ANAE+% of lymphocyte through the whole period( P<0.01), and promoted ether extract apparent deposit rate at the later stage( p<0.05); Dietary vitamin A levels (1500 IU/kg) significantly increased with crude protein apparent deposit rate at the early stage(P<0.05), but high vitamin A significantly suppressed crude protein apparent deposit rate and serum insulin concentration , Vitamin A supplemental level was 5000 IU/kg diet. Cu-VA interaction significantly(P<0.05) affected body weight gain at the end of week 4, feed: gain ratio through the whole stage, ANAE+% of lymphocyte at the end of week 7, serum CuZn-SOD, insulin concentration, at the end of week 4 (P<0.01) .Cu(8 mg/kg)×V1tamin A(5000 IU/kg) interactive group was highest on performance, immunology competence, serum CuZn-SOD activity and ether extract apparent deposit rate.