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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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Huang Wenzhen Huang Buyu Dong Xun 《保鲜与加工》1993,(1):72-77
Based upon the eigenvalue sensitivity theory of non-self-adjoit system and the component mode synthesis method,a new technique is developed to analyze the eigenvalue sensitivity to variation of parameters of large rotor-bearing system. As an application, the influence of the journal bearing parameters on the stability of a large domestic turbine-generator set is analyzed and discussed. 相似文献
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油葵收获割台工作性能仿真及试验研究 总被引:2,自引:0,他引:2
为研究油葵收获割台在工作过程中的性能与可靠性,得到该割台正常工作时的关键参数,利用SOLIDWORKS对割台进行三维参数化建模并导入ADAMS中进行运动学仿真,得到收获时茎秆受力和摆动程度的仿真结果并进行正交组合分析,仿真和分析结果表明:割台正常工作最优参数的组合是拉茎辊转速800 r/min、机器的行驶速度2.12 km/h、拉茎间隙10 mm、拉茎辊的倾角20°,同时往复切割刀的切割速度2 m/s时茎秆的受力最小,通过田间试验发现整个收获过程籽粒损失率≤3%,喂入输送绞龙的茎秆较短,收获可靠性较好,结果表明该割台适合油葵的机械化收获。 相似文献
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珍珠油杏以果面光洁油亮、果肉金黄蜜甜、可溶性固形物含量高而赢得消费者的喜爱,但是该品种存在近成熟期果实糖化、遇雨容易裂果的生理缺陷,生产者普遍认为栽培管理难度较大,遇到采收期降雨量较大的年份,裂果率会达到90%以上,基本失去商品价值。所以,珍珠油杏在沂蒙山区的推广面积一直不大,量少质优必然价高,近几年珍珠油杏田间收购价常常徘徊在12元/kg,单位收益相当可观。据此,围绕解决裂果生产难题,探索珍珠油杏简易设施避雨栽培技术,具有较大的生产意义。我们于2019年在费县东蒙镇太白庄村开展了避雨栽培技术研究,采取了高垄大小行栽培、树盘覆盖无纺布、节水灌溉、拱棚动态覆膜等技术措施,增强了花期冻害防御能力,提高了座坐果率,成功降低了根际土壤湿度和园内空气湿度,实现了优质果率94%、裂果率低于5%,配套技术成熟,具备较强的推广应用价值。 相似文献
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A 2-year field study was conducted to determine the effects of different nutrition systems and Salsola kali subsp. tragus densities on industrial hemp yield and its components. Experiments were conducted as a split plot in a randomised complete block design with three replicates. Factors were fertilisation (poultry manure, vermicompost and nitrogen fertiliser) as the main plot and weed density (0, 5, 10, 15 and 20 plants/m2) as the subplot. Results indicated that the maximum number of racemes per plant, seeds per raceme, 1000-seed weight, biomass, grain yield and harvest index (HI) of industrial hemp were obtained using vermicompost and were reduced with nitrogen fertiliser application. All measured properties in hemp plants decreased due to increasing S. kali subsp. tragus density, especially at 15 and 20 plants/m2. The most significant reduction in hemp grain yield and its components was observed by increasing weed density with the application of nitrogen fertiliser. The application of vermicompost at high weed densities resulted in greater hemp grain yield and its components compared with nitrogen fertiliser. It is recommended to apply organic fertilisers, especially vermicompost at high S. kali subsp. tragus densities. 相似文献
28.
Certification of sustainable palm oil as organised through the Round Table on Sustainable Palm Oil is based on a simplified understanding of the global palm oil value chain – according to which instructions about production practices can be directly translated from the palm oil mill to the primary producer. The reality of palm oil provision is much more complex than this as is shown in the case of Thailand. On the basis of qualitative field study in Southern Thailand this paper clarifies that intermediary stages, such as the collection of oil palm fruit bunches at the ramp, play a key role in the organisation of the chain. The fluidity and complexity of the palm oil flow at the local level complicates the promotion of sustainability through certification. Global and national stakeholders, such as processing and trading firms, non‐governmental organisations and national governments, should therefore open this black box of local dynamics to more effectively contribute to sustainability in palm oil supply. 相似文献
29.
二十碳五烯酸甲酯标准样品的研制 总被引:2,自引:0,他引:2
以深海鱼油为基础原料,将其皂化水解为游离脂肪酸,经尿素—甲醇包合粗分离后,以硫酸—甲醇甲酯化,再经硝酸银—硅胶柱层析精分离,得到高纯度的二十碳五烯酸甲酯标准物质。经定值检测,确定其化合物纯度≥98%。 相似文献
30.
二步法催化高酸值大豆油制备生物柴油 总被引:1,自引:0,他引:1
采用两步法催化高酸值大豆油制备生物柴油.第一步在固定床反应器中,以002CR型阳离子交换树脂为催化剂,高酸值大豆油中游离脂肪酸和甲醇酯化生成脂肪酸甲酯(生物柴油);然后用氢氧化钾催化油中的甘油三酯和甲醇进行酯交换.结果表明,最佳酯化条件为:醇酸摩尔比2:1,反应温度60℃,进耕速度3 mL/min.该条件下大豆油酸值可降至1 mgKOH/g以下.酯交换条件为:催化剂用量1.5%,醇油摩尔比6:1,反应温度65℃.产品技术指标达到我国0#柴油(GB252-1994优级品)的要求. 相似文献