【摘要】 【目的】探究女贞子提取物（Ligustrum lucidum extract, LLE）对高能低蛋白日粮下蛋鸡抗氧化、脂质代谢及肝微观结构的影响。【方法】选用体质量均匀、健康的360只500日龄海兰褐蛋鸡，随机分为6组，每组3个重复，每个重复20只。对照组（试验Ⅰ组）饲喂玉米-豆粕型基础饲粮，试验Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组饲喂高能低蛋白日粮，并在日粮中分别添加0、500、1 000、1 500、2 000 mg·kg^-1的LLE,试验期30 d。翅静脉取血，解剖取蛋鸡肝、腹脂，测定肝指数、腹脂率、肝脂率及血清和肝抗氧化指标，并采用苏木精-伊红染色法和透视电镜研究肝脂肪沉积和亚单位病变。【结果】1)与对照组相比，试验Ⅱ组肝指数、腹脂率及肝脂率分别显著上升了54.02%、170.41%和181.60%。2)饲粮中添加1 500 mg·kg^-1的LLE可显著提高血清和肝中谷胱甘肽过氧化物酶活性，降低丙二醛含量。3)LLE对血清甘油三酯（total glyceride, TG）和总胆固醇（total cholesterol, TC）无显著影响；添加1 000和2 000 mg·kg^-1的LLE可显著降低肝中TG和TC浓度；添加500、1 000、1 500和2 000 mg·kg^-1的LLE均显著降低了血清中的谷丙转氨酶（alanine aminotransferase, ALT）以及肝中的谷草转氨酶（aspartate aminotransferase, AST）和ALT活性。4)代谢能11.75 MJ·kg^-1、粗蛋白质量分数13%的日粮可引起产蛋后期蛋鸡肝脂肪积累、线粒体肿胀以及基质减少等微观病变，添加LLE可预防和缓解以上病理变化。【结论】饲粮中添加LLE可改善产蛋后期蛋鸡抗氧化能力、脂质代谢水平及线粒体功能引起的脂肪肝综合征。更多还原

【Abstract】 【Objective】 This experiment was conducted to investigate the effects of Ligustrum lucidum extract（LLE） on antioxidation, lipid metabolism and liver microstructure of laying hens fed with high-energy and low-protein diet.【Method】A total of 360 Hy-Line Brown laying hens aged 500 days were randomly divided into 6 groups with 3 replicates in each group and 20 chickens in each replicate. The control group（I group） was fed with corn soybean meal basal diet, and the experimental groups Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ were fed with high energy and low protein diet, and the diets were supplemented with 0, 500, 1 000, 1 500 and 2 000 mg·kg^-1 of Ligustrum lucidum extract respectively. The experiment lasted for 30 days. Blood was collected from wing vein, liver and abdominal fat were dissected, and the liver index, abdominal fat percentage, liver fat percentage and serum and liver antioxidant indexes were detemined. And hematoxylin-Eosin（HE） staining and fluoroscopic electron microscopy were used to study the liver fat deposition and subunit lesions. 【Result】 1) Compared with the control group, the liver index, abdominal fat rate and liver fat rate of experimental group Ⅱ significantly increased by 54.02%, 170.41% and 181.60%, respectively. 2) Dietary supplementation of 1 500 mg·kg^-1 LLE could significantly increase GSH-Px levels in serum and liver, and decrease MDA levels. 3) Ligustrum lucidum extract had no significant effect on serum TG and TC levels; however, dietary supplementation of Ligustrum lucidum extract at 1 000 mg·kg^-1 and 2 000 mg·kg^-1 levels significantly decreased the levels of TG and TC in liver, and supplementation at 500, 1 000, 1 500 and 2 000 mg·kg^-1 levels significantly reduced the level of ALT in serum and the level of AST and ALT activity in liver. 4) The diet with metabolizable energy 11.75 MJ·kg^-1 and crude protein 13% could cause liver fat accumulation, mitochondrial swelling, matrix reduction and other micro pathological changes in the late laying period of laying hens, while the addition of Ligustrum lucidum extract could prevent and alleviate the above pathological changes. 【Conclusion】The results suggested that dietary supplementation of Ligustrum lucidum extract could improve the antioxidant capacity, lipid metabolism and mitochondrial function of fatty liver syndrome in laying hens at the late laying stage.更多还原