Effects of supplemental copper-methionine chelate and copper-soy proteinate on the performance, blood parameters, liver mineral content, and intestinal microflora of broiler chickens

SUMMARY In this study, we investigated the effect of dietary supplementation of Cu-Met chelate (CuMet) and Cu-soy proteinate (Cu-SP) on the performance, blood parameters, liver mineral content, and intestinal microflora in broiler chickens. A total of 1,008 hatched Ross broiler chickens were randomly assigned to 1 of 6 dietary treatments (T): T1, control; T2, antibiotic (6 ppm of avilamycin); T3, 50 ppm of Cu as Cu-Met; T4, 100 ppm of Cu as Cu-Met; T5, 50 ppm of Cu as Cu-SP; and T6, 100 ppm of Cu as Cu-SP. Each treatment had 3 replicates of 56 birds (28 birds of each sex). During the 4-wk feeding period, the BW increase of birds in the antibiotic treatment was 3.25% and those of birds in the 100 ppm of Cu treatments were 2.67% on average compared with the control group. The production efficiency factor {[livability (%) × live weight (kg)/age (d) × FCR] × 100} was increased by 5.23% for birds in the antibiotic treatment and by 0.7 to 7.8% for birds in Cu treatments, among which the treatment with 100 ppm of Cu as Cu-SP was highest. The red blood cell level, hematocrit level, and mean corpuscular volume of birds in the Cu treatments were lower than were those of birds in the control group. Copper concentration in the liver increased as the level of Cu supplementation increased. The populations of lactobacilli and total bacteria increased, and that of Escherichia coli decreased as the level of Cu increased, whereas all microbes, including Clostridium perfringens, decreased in the antibiotic treatment.