Zhu Cui, Lv Hang, Chen Zhuang, Wang Li, Wu Xiuju, Chen Zhongjian, Zhang Weina, Liang Rui, Jiang Zongyong
Ministry of Agriculture Key Laboratory of Animal Nutrition and Feed Science (South China), Guangdong Public Laboratory of Animal Breeding and Nutrition, Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China.
Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China.
Biol Trace Elem Res. 2017 Feb;175(2):331-338. doi: 10.1007/s12011-016-0767-3. Epub 2016 Jun 23.
The current study was conducted to investigate the effects of dietary zinc oxide (ZnO) on the antioxidant capacity, small intestine development, and jejunal gene expression in weaned piglets. Ninety-six 21-day-old piglets were randomly assigned to three dietary treatments. Each treatment had eight replicates with four piglets per replicate. The piglets were fed either control diet (control) or control diet supplemented with in-feed antibiotics (300 mg/kg chlortetracycline and 60 mg/kg colistin sulfate) or pharmacological doses of ZnO (3000 mg/kg). The experiment lasted 4 weeks. Blood samples were collected at days 14 and 28, while intestinal samples were harvested at day 28 of the experiment. Dietary high doses of ZnO supplementation significantly increased the body weight (BW) at day 14 and average daily gain (ADG) of days 1 to 14 in weaned piglets, when compared to control group (P < 0.05). The incidence of diarrhea of piglets fed ZnO-supplemented diets, at either days 1 to 14, days 14 to 28, or the overall experimental period, was significantly decreased in comparison with those in other groups (P < 0.05). Supplementation with ZnO increased the villus height of the duodenum and ileum in weaned piglets and decreased the crypt depth of the duodenum, when compared to the other groups (P < 0.05). Dietary ZnO supplementation decreased the malondialdehyde (MDA) concentration at either day 14 or day 28, but increased total superoxide dismutase (T-SOD) at day 14, when compared to that in the control (P < 0.05). ZnO supplementation upregulated the messenger RNA (mRNA) expression of zonula occludens-1 (ZO-1) and occludin in the jejunum mucosa of weaned piglets, compared to those in the control (P < 0.05). The pro-inflammatory cytokine interleukin-lβ (IL-1β) mRNA expression in the jejunum mucosa was downregulated in the ZnO-supplemented group, compared with the control (P < 0.05). Both in-feed antibiotics and ZnO supplementation decreased the mRNA expression of interferon-γ (IFN-γ), but increased the mRNA expression of transforming growth factor-β (TGF-β), in the jejunum mucosa of piglets, when compared to those in the control (P < 0.05). In summary, supplemental ZnO was effective on the prevention of post-weaning diarrhea (PWD) in weaned piglets and showed comparative growth-promoting effect on in-feed antibiotics, probably by the mechanism of improvement of the antioxidant capacity, restoration of intestinal barrier function and development, and modulation of immune functions.
本研究旨在探讨日粮中氧化锌（ZnO）对断奶仔猪抗氧化能力、小肠发育及空肠基因表达的影响。96头21日龄仔猪被随机分为三种日粮处理组。每个处理组有8个重复，每个重复4头仔猪。仔猪分别饲喂对照日粮（对照组）、添加饲料抗生素（300mg/kg金霉素和60mg/kg硫酸黏菌素）的对照日粮或药理剂量的ZnO（3000mg/kg）。实验持续4周。在第14天和第28天采集血样，在实验第28天采集肠道样本。与对照组相比，日粮中添加高剂量ZnO显著提高了断奶仔猪第14天的体重（BW）和第1至14天的平均日增重（ADG）（P<0.05）。与其他组相比，在第1至14天、第14至28天或整个实验期内，饲喂添加ZnO日粮的仔猪腹泻发生率显著降低（P<0.05）。与其他组相比，添加ZnO增加了断奶仔猪十二指肠和回肠的绒毛高度，降低了十二指肠的隐窝深度（P<0.05）。与对照组相比，日粮中添加ZnO在第14天或第28天降低了丙二醛（MDA）浓度，但在第14天增加了总超氧化物歧化酶（T-SOD）（P<0.05）。与对照组相比，添加ZnO上调了断奶仔猪空肠黏膜中紧密连接蛋白-1（ZO-1）和闭合蛋白的信使核糖核酸（mRNA）表达（P<0.05）。与对照组相比，添加ZnO组空肠黏膜中促炎细胞因子白细胞介素-1β（IL-1β）mRNA表达下调（P<0.05）。与对照组相比，饲料抗生素和ZnO添加均降低了仔猪空肠黏膜中干扰素-γ（IFN-γ）的mRNA表达，但增加了转化生长因子-β（TGF-β）的mRNA表达（P<0.05）。综上所述，补充ZnO对预防断奶仔猪断奶后腹泻（PWD）有效，并且对饲料抗生素显示出相当的促生长作用，可能是通过提高抗氧化能力、恢复肠道屏障功能和发育以及调节免疫功能的机制实现的。
