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Jichen Chen Jianchao Yang Hong Du Muhmmad Aslam Wanna Wang Weizhou Chen Tangcheng Li Zhengyi Liu Xiaojuan Liu 《Marine drugs》2021,19(10)
During the processes of primary and secondary endosymbiosis, different microalgae evolved to synthesis different storage polysaccharides. In stramenopiles, the main storage polysaccharides are β-1,3-glucan, or laminarin, in vacuoles. Currently, laminarin is gaining considerable attention due to its application in the food, cosmetic and pharmaceuticals industries, and also its importance in global biogeochemical cycles (especially in the ocean carbon cycle). In this review, the structures, composition, contents, and bioactivity of laminarin were summarized in different algae. It was shown that the general features of laminarin are species-dependence. Furthermore, the proposed biosynthesis and catabolism pathways of laminarin, functions of key genes, and diel regulation of laminarin were also depicted and comprehensively discussed for the first time. However, the complete pathways, functions of genes, and diel regulatory mechanisms of laminarin require more biomolecular studies. This review provides more useful information and identifies the knowledge gap regarding the future studies of laminarin and its applications. 相似文献
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二化螟是我国水稻的重要钻蛀性害虫,常年发生危害严重,给水稻生产带来巨大产量损失。寄生蜂是二化螟重要的生态调节因子和生物防控天敌资源,对田间二化螟的种群数量具有明显的自然控制作用。本文主要就二化螟寄生蜂多样性及其影响因素、二化螟卵寄生蜂和幼虫寄生蜂生态控害功能及优势种利用、二化螟幼虫越冬滞育期间寄生蜂对越冬幼虫种群基数的控制和寄生蜂生态控害功能的评估等方面的研究与应用进行综述,并探讨寄生蜂对二化螟生态控害功能的评估,尝试提出二化螟寄生蜂生态控害功能研究应在越冬代重视二化螟盘绒茧蜂、稻螟小腹茧蜂和中华钝唇姬蜂对越冬滞育幼虫的生态控害潜力、非越冬世代则重点发掘稻螟赤眼蜂、螟黄赤眼蜂和玉米螟赤眼蜂等卵期优势寄生蜂以降低田间二化螟卵的孵化率、减轻二化螟幼虫为害率,以期为提升寄生蜂的生态控害功能提供参考。 相似文献
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Studies on supplementary desalted mother liquor on digestibility of nutrients,ruminal fermentation,and energy and nitrogen balance in Thai native cattle 
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下载免费PDF全文 Takashi Sakai Wanna Angthong Motoharu Takeda Kazato Oishi Hiroyuki Hirooka Hajime Kumagai 《Animal Science Journal》2017,88(9):1337-1345
Four Thai native steers were used to determine the adequate levels of supplementary desalted mother liquor (DML) for energy and nitrogen balances and ruminal fermentation. The crude protein and sodium chloride contents of DML were 25.5% and 60.3% on a dry matter (DM) basis, respectively. A 4 × 4 Latin square design experiment was conducted by adding different amounts of DML to three experimental diets (T1: 1.1%, T2: 2.2%, T3: 3.4% sodium chloride concentration with supplementary DML on a DM basis) and comparing their effects with those of a control diet (C) containing 1.0% commercial salt on a DM basis. The animals were given the experimental diets and rice straw daily at 1.2% and 0.8% of body weight, respectively, on a DM basis. No significant differences in the apparent digestibility of nutrients were observed among treatments. T3 achieved the lowest nitrogen retention (P < 0.05), followed by C, T2 and T1. The ratios of energy retention to gross energy were higher in T1 and T3 than T2, and that in C was lowest (P < 0.05). Supplementary NaCl concentration at 1% and 2% can be replaced with DML without an adverse effect on the digestibility of nutrients or on the nitrogen and energy retention. 相似文献
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Tomoyuki Suzuki Kritapon Sommart Wanna Angthong Thu Van Nguyen Anan Chaokaur Peerapot Nitipot Arun Phromloungsri Yimin Cai Takashi Sakai Takehiro Nishida Fuminori Terada Tomoyuki Kawashima 《Animal Science Journal》2018,89(9):1287-1295
We conducted a meta‐data analysis to develop prediction equations to estimate enteric methane (CH4) emission from beef cattle in Southeast Asia. The dataset was obtained from 25 studies, which included 332 individual observations on nutrient intakes, digestibilities, and CH4 emissions. Cattle were provided tropical forage or rice straw, with or without concentrates in individual pens equipped with indirect open‐circuit head hood apparatus. The simplest and best equation to predict daily CH4 emission was CH4 (g/day) = 22.71 (±1.008) × dry matter intake (DMI, kg/day) + 8.91 (±10.896) [R2 = 0.77; root mean square error (RMSE) = 19.363 g/day]. The best equation to predict CH4 energy as a proportion of gross energy intake (CH4‐E/GEI, J/100 J) was obtained using DMI per body weight (DMIBW, kg/100 kg), content (g/100 g DM) of ether extract (EE) and crude protein (CP), and DM digestibility (DMD, g/100 g); CH4‐E/GEI = ?0.782 (±0.2526) DMIBW ? 0.436 (±0.0548) EE ? 0.073 (±0.0218) CP + 0.049 (±0.0097) DMD + 8.654 (±0.6517) (R2 = 0.39; RMSE = 1.3479 J/100 J GEI). It was indicated that CH4 emissions from beef cattle in Southeast Asia are predictable using present developed models including simple indices. 相似文献
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樟颈曼盲蝽的生活史、生物学习性及若虫的形态 总被引：1，自引：0，他引：1
研究了上海市水源涵养林内樟颈曼盲蝽(Mansoniella cinnamomi(Zheng et Liu,1992))的生活史和生物学习性,以及若虫的龄期划分和各龄若虫的形态特征.依据樟颈曼盲蝽若虫头宽值频次和形态特征,其若虫共分5龄,1～5龄若虫的头宽值分别为(0.23±0.03)、(0.34±0.02)、(0.47±0.03)、(0.57±0.02)、(0.68±0.03) mm,并详细描述了各龄若虫的形态特征.该虫在上海地区一年发生4代,以卵在叶柄、叶主脉及嫩梢皮层内越冬,具有明显的世代重叠现象.确定了樟颈曼盲蝽各世代的发生历期,编制了其在上海地区的生活史表,详细观察记录了成虫的羽化、交尾、产卵等习性和若虫的活动、取食及脱皮等习性. 相似文献
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Chinese mitten crab is a unique aquatic product in China. As a highly nutritious, delicious, and intriguing food, it is deeply loved by consumers. Through field visits and household interviews in Chongming District of Shanghai and Suzhou of Jiangsu Province, the author collected relevant materials and made a detailed analysis of the strengths and weaknesses, opportunities and threats of the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai by using SWOT model. The results show that the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai can adopt growth‐oriented, transformation and upgrading, diversification and defensive development strategies. It is expected to promote the sustainable development of Chinese mitten crab industry in Shanghai through the development and application of crab culture. 相似文献
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Iyapa Palang Ikuo Hirono Saengchan Senapin Wanna Sirimanapong Boonsirm Withyachumnarnkul Rapeepun Vanichviriyakit 《Journal of fish diseases》2020,43(10):1229-1236
Streptococcus agalactiae secrete virulence factors believed to be able of killing host tissues, especially under elevated water temperature. A direct effect of S. agalactiae secretory products on tilapia cells was tested on the tilapia kidney (TK-1) cell culture. The bacteria were cultured under four different temperature levels: 22, 29, 32 and 37°C; the cell-free portion was processed through SDS-PAGE; and distinct bands were identified by LC-MS/MS. At least, three virulence factors were identified, Bsp, PcsB and CAMP factor, with increasing levels as the cultured temperature rose. Expressions of bsp, pcsB and cfb were also up-regulated with the rising of the temperature in S. agalactiae culture. The supernatant from the bacteria cultured under specified temperatures was added into TK-1 cell-cultured wells. Morphological damage and mortality of the cultured cells, as determined by MTT method, were increased progressively from the supernatant treatment according to the rise of temperature in S. agalactiae culture. This study suggests that the production of the three virulence factors of S. agalactiae reported herein is temperature-dependent, and it is likely that CAMP factor directly kills the TK-1 cells since the other two types of protein are involved in S. agalactiae cell division and the bacterial adherence to host tissues. 相似文献
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Daisuke Kawauchi Wanna Angthong Ornvimol Keaokliang Tetsuya Ishida Toshihiro Takahashi Tomoyuki Kawashima 《Animal Science Journal》2021,92(1):e13531
The purpose of this study was to investigate the effects of feeding Bacillus subtilis on rumen fermentation, blood metabolites, nutrient digestibility, and energy and nitrogen balances in non-lactating crossbred (Holstein-Friesian × Bos indicus) cows. Four cows were assigned to the control and B. subtilis diets in a crossover design, and respiratory and metabolic experiments were conducted. For the B. subtilis diet, B. subtilis DSM15544 spores were added at the rate of 1.0 × 1010 CFU/head/day to the control diet. At 4 hr after feeding, cows fed the B. subtilis diet had increased levels of i-butyric acid in the rumen fluid and tended to have lower concentrations of plasma non-esterified fatty acids when compared with cows fed the control diet. This suggests that feeding B. subtilis could improve energy efficiency. However, there was no effect on energy retention in this study. Although there were no effects on nutrient digestibility, nitrogen balance, or methane production, heat production was significantly higher in cows fed the B. subtilis diet than in those fed the control diet. 相似文献
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通过应用高清数码摄相机手段,系统监测了蝶蛹金小蜂寄生黑纹粉蝶蛹的产卵习性。结果发现,蝶蛹金小蜂寄生黑纹粉蝶蛹的产卵过程可分为守卫、探查、产卵、整理4个阶段。蝶蛹金小蜂可以很好地寄生黑纹粉蝶蛹,暗期寄生产卵活动频次较少,光期后寄生产卵活动逐渐增加,寄生产卵活动呈现明显的昼夜节律。寄生产卵频次和时间分配主要集中在11:00— 17:00,其中14:00— 15:00为寄生蜂产卵高峰期。蝶蛹金小蜂寄生黑纹粉蝶蛹产卵活动频次分配率与产卵耗时分布呈正相关,单头黑纹粉蝶蛹体内产生的蝶蛹金小蜂后代数量随累计产卵时间和产卵频次增加而显著增多。随着寄主从预蛹发育到3日龄蛹,蝶蛹金小蜂单次寄生产卵耗时延长,且相对偏好选择在1日龄蛹体上寄生产卵。 相似文献