Department of Animal Science, Universidade Federal de Viçosa, Viçosa, 36570900, Brazil.
Pettigrew Research Services, Arizona, 85646, USA.
BMC Vet Res. 2022 Jun 13;18(1):223. doi: 10.1186/s12917-022-03286-5.
Five hundred 8-d old male broilers Cobb500 were randomly allotted into 10 treatments in factorial arrangement with 5 Cu levels (0, 4, 8, 12, and 16 mg/kg), and 2 sources (Cu proteinate, CuPro and Cu sulphate, CuSO4.5H2O) for a 10-d-experiment.
Feed conversion ratio (FCR) was better (P < 0.05) in CuPro fed chicks compared with CuSO4.5H2O group. Average daily feed intake (ADFI) decreased linearly (P < 0.05) as dietary Cu increased. A quadratic response (P < 0.05) to Cu levels was found for FCR, being optimized at 9.87 and 8.84 mg Cu/kg in CuPro and CuSO4.5H2O diets, respectively. Copper supplementation linearly increased liver Cu content (P < 0.05) and tended to linearly increase (P = 0.07) phosphorus (P) and copper in tibia. Manganese and zinc were higher (P < 0.05) in tibia of CuPro fed birds. Broilers fed CuPro exhibited lower liver iron (P < 0.05) content, lower activities of Cu, Zn superoxide dismutase (CuZnSOD) in breast muscle and liver, and glutathione peroxidase in liver. Glutathione peroxidase reduced linearly (P < 0.05) with CuPro levels and increased linearly (P < 0.05) with CuSO4.5H2O levels and were lower (P < 0.05) in all CuPro levels in breast muscle. Breast muscle malondialdehyde concentration tended to be higher (P = 0.08) in broilers fed CuSO4.5H2O. Copper levels linearly increased (P < 0.05) metallothionein (MT) and malate dehydrogenase (MDH) expression in liver, and six-transmembrane epithelial antigen of the prostate-1 (STEAP-1) in the intestine. Copper elicited a quadratic response (P < 0.050) in AKT-1 and mammalian target of rapamycin (mTOR) in breast muscle, CuZnSOD in liver and antioxidant 1 copper chaperone (ATOX 1) in intestine. Broilers fed CuPro exhibited higher mRNA expression of mTOR in muscle breast and lower CuZnSOD in liver and ATOX 1 in intestine. Interaction (P < 0.05) between levels and sources was found in mRNA expression for GSK-3β, MT, and CuZnSOD in breast muscle, FAS and LPL in liver and MT and CTR1 in intestine.
CuPro showed beneficial effects on feed conversion and bone mineralization. Organic and inorganic Cu requirements are 9.87 and 8.84 mg Cu/kg, respectively.
500 只 8 日龄雄性肉鸡 Cobb500 被随机分配到 10 个处理组中，采用因子设计，有 5 个铜水平（0、4、8、12 和 16mg/kg）和 2 种来源（铜蛋白、CuPro 和硫酸铜、CuSO4.5H2O），进行了 10 天的实验。
与 CuSO4.5H2O 组相比，CuPro 喂养的雏鸡的饲料转化率（FCR）更好（P<0.05）。随着饲料中铜含量的增加，平均日采食量（ADFI）呈线性下降（P<0.05）。FCR 对铜水平呈二次响应（P<0.05），CuPro 和 CuSO4.5H2O 饲料中的优化水平分别为 9.87 和 8.84mg Cu/kg。铜的补充量线性增加（P<0.05）肝脏铜含量，并倾向于线性增加（P=0.07）胫骨中的磷（P）和铜。CuPro 喂养的鸟类胫骨中的锰和锌含量较高（P<0.05）。CuPro 喂养的肉鸡肝脏铁含量较低（P<0.05），胸肌和肝脏中铜、锌超氧化物歧化酶（CuZnSOD）和肝脏中的谷胱甘肽过氧化物酶活性较低。谷胱甘肽过氧化物酶的活性随着 CuPro 水平的降低而呈线性降低（P<0.05），随着 CuSO4.5H2O 水平的增加而呈线性增加（P<0.05），并且在所有 CuPro 水平下，胸肌中的谷胱甘肽过氧化物酶活性均较低（P<0.05）。在肌肉中，与喂食 CuSO4.5H2O 的肉鸡相比，丙二醛的浓度趋于升高（P=0.08）。铜水平在线性增加（P<0.05）肝脏中的金属硫蛋白（MT）和苹果酸脱氢酶（MDH）的表达，以及肠道中的六跨膜上皮抗原 1（STEAP-1）。铜在胸肌中的 AKT-1 和哺乳动物雷帕霉素靶蛋白（mTOR）、肝脏中的 CuZnSOD 和肠道中的铜伴侣 1 （ATOX 1）呈二次响应（P<0.05）。与喂食 CuPro 的肉鸡相比，肌肉中 mTOR 的 mRNA 表达较高，而肝脏中的 CuZnSOD 和肠道中的 ATOX 1 表达较低。在胸肌中，GSK-3β、MT 和 CuZnSOD 的 mRNA 表达，肝脏中的 FAS 和 LPL 以及肠道中的 MT 和 CTR1 的表达，均存在铜水平和来源之间的交互作用（P<0.05）。
CuPro 对饲料转化率和骨骼矿化有有益的影响。有机铜和无机铜的需求量分别为 9.87 和 8.84mg Cu/kg。
