Background: Copper is an essential microelement for animals and has been used at pharmacological doses in weaned piglets to improve growth performance. However, it also induces systemic oxidative stress after short-term feeding. The aim of this study was to investigate the effects of dose and duration of dietary copper on lipid peroxidation and oxidative stress status in model of weaned piglets. Methods: A total of 48 crossbred piglets (weaned at 21d, weight ∼8.2 kg) were randomly assigned into 4 groups of 12 in each. The control group and 3 treatment groups fed with basal diet supplemented with 20, 100 and 200 mg/kg copper as copper sulfate for 3 and 6 weeks, respectively. Results: Dietary copper supplementation significantly affected the activities of ALP, LDH, LIPC and the levels of Ca and TG in serum as well as the copper and zinc deposition in liver. Increased MDA concentrations, and decreased GPX, CP and CAT concentrations in serum were found in 0, 100 and 200 mg Cu/kg diet groups at 3 weeks post weaning. Hepatic lipid peroxidation was also induced in these groups indicated from hepatic SOD1, GPX1, CAT, CP, MT1A and MT2A transcriptional levels. Those adverse symptoms were alleviative at 6 weeks post weaning. The hepatic Cu and Zn concentrations, serum MDA concentrations, and serum CAT and GPX activities were significantly correlated with Actinobacillus, Lactobacillus, Sarcina, Helicobacter, Campylobacterales, which could affect the intestinal health further. Conclusion: These results indicated that copper deficiency or over supplementation would affect the systemic lipid peroxidation. These adverse changes were not observed when the dietary copper concentration at 20 mg Cu/kg diet. The results suggested the appropriate dietary copper concentration is around 20 mg Cu/kg diet, and its range might be much stricter than we thought.

背景：铜是动物必需的微量元素，已以药理剂量用于断奶仔猪，以改善生长性能。然而，短期喂养后它也会诱发全身氧化应激。本研究的目的是探讨日粮铜的剂量和持续时间对断奶仔猪模型脂质过氧化和氧化应激状态的影响。方法：将48头杂交仔猪（21天断奶，体重~8.2 kg）随机分为4组，每组12头。对照组和3个治疗组在基础日粮中分别添加20、100和200mg/kg硫酸铜，连续喂养3周和6周。结果：膳食补铜显着影响血清ALP、LDH、LIPC活性、Ca、TG水平以及肝脏铜、锌沉积。断奶后 3 周，0、100 和 200 mg Cu/kg 饮食组的血清中 MDA 浓度升高，GPX、CP 和 CAT 浓度降低。从肝脏 SOD1、GPX1、CAT、CP、MT1A 和 MT2A 转录水平表明，这些组中也诱导了肝脏脂质过氧化。这些不良症状在断奶后 6 周得到缓解。肝脏Cu、Zn浓度、血清MDA浓度、血清CAT、GPX活性与放线杆菌、乳酸菌、八叠球菌、螺杆菌、弯曲杆菌显着相关，进一步影响肠道健康。结论：这些结果表明铜缺乏或过量补充会影响全身脂质过氧化。当日粮铜浓度为 20 mg Cu/kg 日粮时，没有观察到这些不利变化。 结果表明，适宜的膳食铜浓度约为20毫克铜/公斤膳食，其范围可能比我们想象的要严格得多。