| 摘要: |
| 【目的】探究不同用量纳米氧化铜（nano-CuO）对藏鸡生产性能及肝组织原癌基因（c-Myc）表达的影响。【方法】取14日龄藏鸡120羽，随机分为空白对照组和低、中、高不同剂量nano-CuO组，每组设置3个重复，空白对照组藏鸡饲喂基础日粮，nano-CuO低、中、高剂量组藏鸡分别饲喂添加5，50和100 mg/kg nano-CuO的基础日粮，试验为期14 d。试验开始和结束时分别称量试鸡初始体质量和终末体质量，试验期间统计采食量，测算每组试鸡的平均日增质量、平均日采食量和饲料转化率等生产性能指标。28日龄时采集试鸡肝脏、肾脏样品，检测其金属硫蛋白（metallothionein，MT）含量,用HE染色法检测肾脏的病理学变化,用免疫组化法检测肝组织c-Myc蛋白表达水平，用RT PCR法测定肝组织c-Myc mRNA表达水平的变化。【结果】与对照组相比，添加5~50 mg/kg的nano-CuO能显著提高藏鸡的体质量和平均日增质量（P<0.05），添加100 mg/kg nano-CuO组藏鸡平均日增质量变化不显著（P>0.05），4组藏鸡的平均日采食量和饲料转化率无显著差异（P>0.05）。随nano-CuO添加水平的增加，不同组织中的金属硫蛋白（MT）含量逐渐升高，且肾组织更容易受到nano-CuO添加水平的影响。5 mg/kg nano-CuO组试鸡肾小球结构清晰；50 mg/kg nano-CuO组肾小球毛细血管充血，周围可见少量血细胞；100 mg/kg nano-CuO组肾小球破裂、萎缩，肾小管可见上皮细胞脱落，淋巴细胞浸润。100 mg/kg nano-CuO组试鸡肝组织c-Myc蛋白表达水平高于5和50 mg/kg nano-CuO组，而其c-Myc mRNA表达水平较5和50 mg/kg nano-CuO组极显著升高(P＜0.01)。【结论】100 mg/kg nano-CuO会对藏鸡的肝脏造成一定损害，饲料中的nano-CuO用量以5~50 mg/kg为宜。 |
| 关键词: 纳米氧化铜 藏鸡 c-Myc 金属硫蛋白 |
| DOI： |
| 分类号: |
| 基金项目:西藏自治区厅校联合基金项目（XZ2018ZRG-26(Z)）；西藏自治区科技计划项目（XZ201902NB05） |
|
| Effect of nano-CuO on performance and c-Myc expression in liver of Tibetan chickens |
|
CHANG Zhenyu,DONG Hailong,ZHANG Xiaobing,et al
|
| Abstract: |
| 【Objective】This study investigated the effects of nano-copper oxide (nano-CuO) at different concentrations on performance and liver tissue proto-oncogene (c-Myc) expression of Tibetan chickens.【Method】A total of 120 Tibetan chickens at the age of 14 days were randomly divided into blank control group as well as low,medium and high nano-CuO groups with 3 replicates in each group.Chickens in the blank control group were fed on basal diet,while chickens in the low,medium and high nano-CuO groups were fed on basal diet supplemented with 5,50 and 100 mg/kg nano-CuO,respectively.The experiment lasted for 14 days.The initial and final body weights of chickens were weighed at the beginning and end of the experiment,respectively.During the experiment,the feed intake was counted,and the performance indexes such as average daily gain,average daily feed intake and feed conversion rate of chickens in each group were calculated.At the age of 28 days,liver and kidney samples were collected to detect metallothionein (MT) content.The pathological changes of kidney were detected by HE staining.The expression level of c-Myc protein in liver tissue was detected by immunohistochemistry,and the change of c-Myc mRNA level in liver tissue was determined by RT-PCR.【Result】Compared with the control group,the supplementation of 5-50 mg/kg nano-CuO significantly increased body weight and average daily gain of Tibetan chickens (P<0.05).There was no significant difference in average daily gain between 100 mg/kg nano-CuO group and control group (P>0.05),and there were no significant differences in average daily feed intake and feed conversion rate among all groups (P>0.05).Metallothionein (MT) content in different tissues gradually increased with the increase of nano-CuO supplemental level,and renal tissues were more susceptible.The glomerular structure of the 5 mg/kg nano-CuO group was clear,while the glomerular capillaries of the 50 mg/kg nano-CuO group were hyperemic and a few blood cells could be seen around them.The glomerular rupture and atrophy of the 100 mg/kg nano-CuO group showed epithelial cell shedding and lymphocyte infiltration in renal tubules.The positive expression rate of c-Myc in 100 mg/kg nano-CuO group was higher than that in 5 and 50 mg/kg nano-CuO groups.The mRNA level of c-Myc in 100 mg/kg nano-CuO group was significantly higher than that in 5 and 50 mg/kg nano-CuO groups (P<0.01).【Conclusion】nano-CuO with 100 mg/kg dose had damaging effect on the liver of Tibetan chickens,thus the supplementation should be limited to 5-50 mg/kg. |
| Key words: nano CuO Tibetan chicken c-Myc metallothionein |
