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Dong Ruan Qiuli Fan Ahmed Mohamed Fouad Yunyun Sun Shengshu Huang Aiji Wu Chuxiao Lin Zhixiang Kuang Chang Zhang Shouqun Jiang 《Journal of animal science》2021,99(2)
Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition. 相似文献
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基于2020年3月-2020年10月猪肉价格及新冠肺炎疫情指数,借助VAR模型,定量研究新冠肺炎疫情对于猪肉价格的影响。研究结果表明:新冠肺炎疫情对猪肉价格存在影响,促使猪肉价格上涨,在此基础上文章提出相应措施。 相似文献
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以中间锦鸡儿和玉米、苏丹草、高丹草种子为试材,以蒸馏水为对照,采用培养皿滤纸法,研究了不同梯度(0.5、1.0、5.0、10.0、25.0mg·mL~(-1))中间锦鸡儿花水浸提液对3种受体作物种子萌发及幼苗生长的影响,以期对农林复合系统生产和构建提供理论依据和有益参考。结果表明:随着中间锦鸡儿花水浸提液质量浓度的增加,受体作物玉米、苏丹草、高丹草种子的平均发芽率和发芽指数均表现"低浓度促进,高浓度抑制"效应,但不同质量浓度水浸提液对3种农作物种子发芽的影响有差异性,在质量浓度为1.0mg·mL~(-1)时,3种农作物的种子相对发芽率间无显著差异(P0.05),除玉米外,另外2种受体作物种子的平均发芽率均表现为促进作用,且对高丹草的促进作用最大,RI=13.70%;在高浓度浸提液(C≥5.0mg·mL~(-1))处理下3种受体作物种子的发芽指数与对照均表现显著差异(P0.05)。玉米、苏丹草和高丹草的胚根、胚芽对中间锦鸡儿花水浸提液的化感效应均表现为"浓度效应";3种受体作物的苗高随着浸提液处理浓度的增大表现为"低促高抑",高浓度的浸提液对高丹草幼苗高度的抑制作用最强。花水浸提液对苏丹草和高丹草的幼苗干重化感效应表现为"低促高抑"效应,而对玉米幼苗干重表现为"高浓度抑制"效应。中间锦鸡儿花水浸提液对3种受体作物的化感作用综合效应大小依次为高丹草玉米苏丹草。 相似文献
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Operational Deflection Shapes of large scale electromechanical system can be ex-tracted directly from multipoints response of the operating system by using of the modal shape analy-sis method. Thev can be used for engineers evaluating the practical dynamic beavior of the largescale elecltromechanical system,checking the existence of local reso,iance of the Stibsystem. and in-dentifying the wcakened positions of the rigidity of structure, In this paper the method of measuringand extracting the operational deflection shal1e of the electromecha nical system is given and theavailability of operational deflection shape is proved by analyzing the actual vibration of a large ex-haust fan system as an example. 相似文献
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Information integrating is the most important key to CIMS,which is the base of the function integrating and all others.Because of so many kinds,so complicated structure,so many different sources and uses that the information in CIMS has,it is necessary to build a popular Information Integrating Model. The model of information integrating in the thesis bases on the enterprise model,which is presented by ISO(International Organization for Standardization).According to the object-oriented method,the process of modeling begins with classifying the information,and then describes the definition of the attributes and the structural relation of those objects. By means of the idea of Encapsulation and Inheritance,the destination of information integrating can be arrive and the model of information integrating can be set up. The model which is based on the share information is helpful to finish the function integrating and the whole CIMS' construction. Moreover,the system which is developed following such program can be reused for many times and the developing circle of CIMS can be apparently shortened,too. 相似文献