Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou 510640, P. R. China.
Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou 510640, P. R. China.
Poult Sci. 2021 Mar;100(3):100779. doi: 10.1016/j.psj.2020.10.033. Epub 2020 Nov 5.
The objective of this study was to investigate the effects of dietary copper (Cu) on production, egg quality, and hatchability of Chinese Yellow broiler breeder hens and growth performance of their offspring. A total of 576 30-week-old hens were randomly allotted into 6 groups, each with 6 replicates (8 cages for each replicate with 2 birds per cage). The basal diet contained 3.50 mg/kg Cu, and the other 5 treatment diets contained 8.5, 13.5, 23.5 43.5, and 83.5 mg/kg Cu, respectively, additionally supplemented with Cu on the basal diet. The trial lasted for 15 wk. Qualified egg rate of birds fed 23.5 or 83.5 mg/kg Cu was significantly decreased (P < 0.05) compared with those given 3.5, 8.5, or 13.5 mg/kg Cu. Plasma malondialdehyde concentration showed quadratic effect (P = 0.002) which that decreased first then increased with dietary Cu increased. Highest values of Cu content and hepatic activity of Cu-ATPase occurred in hens fed 83.5 mg/kg dietary Cu with linear (P = 0.001) and quadratic (P = 0.001) effects. Shell strength and proportion on 18th day of live embryos of hens fed 13.5 mg/kg Cu were the greatest compared with other groups respectively (P < 0.05); rate of qualified eggs for hatch and hatchability of fertilized eggs of hens fed 83.5 mg/kg Cu were the least (P < 0.05). In conclusion, both inadequate (3.5 mg/kg diet) and excess (83.5 mg/kg) of dietary Cu can induce oxidative stress in hens and lead to decreased egg quality. Hatchability and growth performance of offspring were decreased when breeder hens were fed excess Cu in spite of greater hatching weight. The appropriate dietary Cu level for Chinese Yellow broiler breeder hens during the egg-laying period is 15.7 to 21.2 mg/kg (1.81-2.44 mg Cu fed per day) when based on Cu level and Cu-ATPase activity in the liver. This dietary Cu requirement is approximately doubled (∼40 mg/kg, ∼4.60 mg Cu per bird per day) for maximal response of eggshell thickness.
本研究旨在探讨饲粮铜（Cu）水平对产蛋性能、蛋品质和孵化率的影响以及对种母鸡后代生长性能的影响。选用 30 周龄的 576 只海兰褐蛋种母鸡，随机分为 6 组，每组 6 个重复，每个重复 8 个笼，每笼 2 只鸡。基础饲粮 Cu 含量为 3.50mg/kg，其他 5 种试验饲粮 Cu 含量分别为 8.5、13.5、23.5、43.5 和 83.5mg/kg，在基础饲粮上额外添加 Cu。试验期为 15 周。与饲粮 3.5、8.5 和 13.5mg/kg Cu 组相比，饲粮 23.5 和 83.5mg/kg Cu 组的母鸡合格种蛋率显著降低（P<0.05）。血浆丙二醛浓度呈二次效应（P=0.002），随饲粮 Cu 水平升高先降低后升高。饲粮 Cu 水平为 83.5mg/kg 时，母鸡肝脏 Cu 含量和铜蓝蛋白活性最高，呈线性和二次效应（P=0.001）。与其他组相比，饲粮 Cu 水平为 13.5mg/kg 时母鸡第 18 天活胚蛋壳强度和蛋壳比率最高（P<0.05）；饲粮 Cu 水平为 83.5mg/kg 时母鸡合格种蛋率和受精蛋孵化率最低（P<0.05）。综上，饲粮 Cu 不足（3.5mg/kg 饲粮）和过量（83.5mg/kg 饲粮）均可诱导母鸡发生氧化应激，导致蛋品质下降。尽管种母鸡后代的孵化体重增加，但当饲粮 Cu 过量时，后代的孵化率和生长性能下降。本研究条件下，中国黄羽肉鸡种母鸡产蛋期饲粮 Cu 适宜水平为 15.721.2mg/kg（1.812.44mg/d），肝脏 Cu 含量和铜蓝蛋白活性处于适宜范围；最大蛋壳厚度对应的饲粮 Cu 需要量约为适宜水平的 2 倍（40mg/kg，4.60mg/d）。
