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1.
Effects of road transportation on metabolic and immunological responses in Holstein heifers 下载免费PDF全文
Hyeok‐Joong Kang In Kyu Lee Min‐Yu Piao Chae‐Won Kwak Min Jeong Gu Cheol Heui Yun Hyun‐Jin Kim Hyeon‐Ju Ahn Hee‐Bal Kim Gyeom‐Heon Kim Soo‐Ki Kim Jong‐Youl Ko Jong K. Ha Myunggi Baik 《Animal Science Journal》2017,88(1):140-148
This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers. 相似文献
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Since the discovery of penicillin in 1928 and throughout the ‘age of antibiotics’ from the 1940s until the 1980s, the detection of novel antibiotics was restricted by lack of knowledge about the distribution and ecology of antibiotic producers in nature. The discovery that a phenazine compound produced by Pseudomonas bacteria could suppress soilborne plant pathogens, and its recovery from rhizosphere soil in 1990, provided the first incontrovertible evidence that natural metabolites could control plant pathogens in the environment and opened a new era in biological control by root‐associated rhizobacteria. More recently, the advent of genomics, the availability of highly sensitive bioanalytical instrumentation, and the discovery of protective endophytes have accelerated progress toward overcoming many of the impediments that until now have limited the exploitation of beneficial plant‐associated microbes to enhance agricultural sustainability. Here, we present key developments that have established the importance of these microbes in the control of pathogens, discuss concepts resulting from the exploration of classical model systems, and highlight advances emerging from ongoing investigations. © 2019 Society of Chemical Industry 相似文献
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陆地棉胚珠及纤维发育过程中miRNA分离与鉴定 总被引:1,自引:0,他引:1
microRNA(miRNA)是生物中一类起负调控作用的非编码的小分子RNA,主要在转录后水平上调节生物体的生长与发育。直接克隆法是鉴定植物中miRNA最常用也是最有效的方法之一。利用直接克隆法分离了陆地棉开花后0~10 d(days post anthesis, DPA)胚珠中总RNA,从中筛选17~24 nt小分子RNA构建cDNA文库,对初筛得到的阳性克隆进行测序。通过与miRNA数据库比对,最终获得4个保守的miRNA。进一步对他们的转录表达进行分析,发现所有miRNA在棉花胚珠纤维不同发育时期均能表达。其中miR167a、miR172c和miR394b在棉花幼苗的根茎叶中有不同程度的表达。预测得到55个miRNA的靶基因,多数靶基因编码转录因子、代谢酶类以及发育相关蛋白,进一步证明miRNA参与调控棉花纤维的形态建成、发育等各项生理活动。 相似文献
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Chang Woo Ji Dae-Seong Lee Da-Yeong Lee Young-Seuk Park Ihn-Sil Kwak 《Ecology of Freshwater Fish》2023,32(1):64-79
We analysed the stomach contents of fish species inhabiting fresh and brackish waters of South Korea to improve our understanding of feeding preferences and competition among them. The stomach contents of 54 fish species contained 237 genera, 187 families, 84 orders, 37 classes and 25 phyla. Faunal food items included 164 genera, 129 families, 47 orders, 23 classes and 16 phyla. Floral food items were relatively limited, comprising 73 genera, 58 families, 37 orders, 14 classes and nine phyla. The most consumed faunal food item was Chironomidae (Diptera), whereas the most consumed floral food item was Fragilariaceae (Fragilariales). The 54 fish species were classified into six groups using hierarchical and nonmetric multidimensional analysis based on their food preferences: Group 1 (G1) fishes were zooplanktivores; group 2 (G2) fishes mainly consumed Malacostraca, Maxillopoda and other fishes (e.g. Osmeriformes); groups 3 (G3) and 4 (G4) consumed Chlorophyta, Cyanobacteria and Bacillariophyta; and groups 5 (G5) and 6 (G6) consumed macroinvertebrates. Network analysis was used to link fishes with their food items. The highest hub score for food items was for macroinvertebrates, including Diptera (13.9), Ephemeroptera (11.1) and Trichoptera (8.2). Niche breadth analysis represented the diversity of food items among the feeding groups (G1–G6). Food item diversity was high for planktivores (G1 and G3) and omnivores (G4). Conversely, the dietary diversity of carnivores (G2) and insectivores (G5) was limited. Competitive relationships between fishes, as represented by the niche overlap in G5 (insectivores), were higher than those between other groups. 相似文献
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Male hybrids from a cross between female mice of strain C57BL/6Kh and males of strain DBA/2J lived longer after injection of P815 mastocytoma cells of DBA/2 origin than did their female siblings. Responses to the histocompatibility antigen on the X chromosome of the DBA/2 strain may be involved in resistance to the tumor. When the female parent was replaced with a C57BL/6Kh carrying one of several mutations in the H-2 region, this sex effect disappeared in some of the hybrid combinations. Thus, the H-2 complex appears to be involved in the regulation of the immune response to the X-linked histocompatibility antigen in this tumor model. 相似文献
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Using two drought resistant wheat (Triticum aestivum L.) cultivars, ‘Changwu134’ and ‘Changhan58,’ a field experiment was conducted in ChangWu Agro-ecological Experiment Station on China's Loess Plateau during 2008 and 2009 to compare the effects of different fertilizer and tillage treatments on the fructan contents as well as fructan exo-hydrolase (FEH) activity in relation to wheat yield. We found that ‘Changhan58’ had greater yield and fructan content in the penultimate internode and higher FEH activity than did ‘Changwu134.’ For ‘Changhan58.’ applying 195 kg·ha?1(120 +75) N plus 45000 kg·ha?1 of pig manure and 120 kg·ha?1 phosphate under conservation tillage produced the highest yield (6769 ka/ha), fructan content in penultimate internode, water use efficiency (WUE), as well as FEH activity among the fertilizer and tillage treatments. Therefore, routine soil management for wheat should focus on combined use of manures and inorganic fertilizer to enhance the amount and transportation efficiency of WSC and ultimately ensure greater yield. 相似文献
10.
Min-Jin Kwak Min-Young Park Yong-Soon Choi Junghwan Cho Duleepa Pathiraja Jonggun Kim Hanbae Lee In-Geol Choi Kwang-Youn Whang 《畜牧与生物技术杂志(英文版)》2022,(1):256-264
Background: Gut is a crucial organ for the host’s defense system due to its filtering action of the intestinal membrane from hazardous foreign substances. One strategy to strengthen the gut epithelial barrier function is to upregulate beneficial microflora populations and their metabolites. Sophorolipid(SPL), which is a glycolipid biosurfactant, could increase beneficial microflora and decrease pathogenic bacteria in the gastrointestinal tract.Therefore, herein, we conducted an experiment with b... 相似文献