Hot-melt extruded copper sulfate affects the growth performance, meat quality, and copper bioavailability of broiler chickens.

This study was conducted to evaluate the effects of the supplementation of diets of broiler chickens with hot-melt extruded CuSO4 (HME-Cu) on their growth performance, nutrient digestibility, gut microbiota, small intestinal morphology, meat quality, and copper (Cu) bioavailability. A total of 225 broilers (Ross 308), one-day old and initial weight 39.14 g, were weighed and distributed between 15 cages (15 birds per cage) in a completely randomized experimental design with 3 treatments (diets) and 5 replicates per treatment. Cages were allotted to three treatments including control (without supplemental Cu), IN-Cu (16 mg/kg of CuSO4), and HME-Cu (16 mg/kg of HME processed CuSO4). The HME-Cu treatment tended to increase the overall body weight gain (p<0.10). The apparent digestibility of Cu was increased by supplementation of HME-Cu at phase 2 (p<0.05). The Escherichia coli count in cecum tended to decrease with the supplementation with Cu (p<0.10). In addition, the HME-Cu treatment had a higher pH of breast meat than the control and IN-Cu treatments (p<0.05). Significant increases in the cooking loss, water-holding capacity, and lightness in the breast were observed in the HME-Cu treatment compared to the control (p<0.05). The Cu content of excreta increased with the Cu supplementation (p<0.05). The concentration of excreta Cu in broilers was decreased in the HME-Cu compared to the IN-Cu in phase 2 (p<0.05). The Cu concentration in the liver was increased with the HME-Cu supplementation, compared with the control diets (p<0.05). This study showed that HME-Cu supplementation at the requirement level (16 mg/kg diets) in broiler diets did not affect the growth performance and the physiological function of Cu in broilers. However, supplementation of Cu in HME form improved the meat quality and the bioavailability of Cu.