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21.
This study was conducted to investigate the effects of compound p1ant nutrients (CPN) on rumen fermentation parameters, rumen microbiota and fatty acid composition of longissimus dorsi musc1e in finishing sma11 tai1 Han sheep. Sixteen 4-month-o1d finishing sma11 tai1 Han sheep with an initia1 body weight (BW) of (24.18±0.31) kg were random1y divided into two groups, name1y, with 8 rep1icates per group and 1 sheep per rep1icate. The sheep in the contro1 group were fed a basa1 diet, whereas the sheep of the contro1 group (CPN group) was fed the basa1 diet supp1ementation with 3‰ CPN. The experiment 1asted for 97 days after 7 days adaption. The resu1ts showed as fo11ows: compared with the contro1 group, 1) adding CPN decreased the concentration of ammonia nitrogen (NH3-N) (P<0.05); 2) CPN supp1ementation affected beta diversity of rumen microbiota; 3) the re1ative abundance of Acidobacteriota, Erysipe1otrichaceae_UCG-002, Lactobacillus, and Megasphaera were enhanced by adding CPN (P<0.05), whereas, the re1ative abundance of Bacteroidetes and Prevotella was 1ower (P<0.05); 4) the supp1ementation of CPN had no significant effect on fatty acid composition of longissimus dorsi musc1e of fattening sma11-tai1ed Han sheep (P>0.05); 5) the contents of tota1 MUFA, C18:1n9c, C14:1, C16:1, C18:2n6c, C18:3n3 and n-3PUFA in the longissimus dorsi musc1e were corre1ated with the re1ative abundance of Megasphaera, Erysipe1otrichaceae_UCG-002, Succiniclasticum and Ruminococcus (P<0.05). In conc1usion, CPN can regu1ate the rumen microbiota structure and reduce the rumen NH3-N concentration of fattening sma11-tai1ed Han sheep. In production practice, CPN can be used as a rumen eco1ogica1 regu1ator. © 2023 Authors. All rights reserved. 相似文献
22.
Omid Khalifezadeh Koureh Mohammadreza Pourghayoumi Majid Majidian 《International Journal of Fruit Science》2019,19(1):1-12
The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds. 相似文献
23.
Eaknarin Ruangrak Weeraya Khummueng 《The Journal of Horticultural Science and Biotechnology》2019,94(3):378-388
Lettuce is grown in different parts of the world and it is beneficial for health. Light condition is one of the most important environmental factor in regulating growth, development, and phytochemical accumulation in lettuce, particularly when lettuce is produced in a hydroponic system. Due to advances in technologies, artificial light sources have become increasingly capable of providing appropriate quality, intensity, and photoperiod of light in hydroponic lettuce production. This review highlights the progress of current research on the effects of artificial light regulation on growth and phytochemical accumulation in lettuce produced in hydroponic systems. 相似文献
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玉米根系分泌物缓解连作花生土壤酚酸类物质的 化感抑制作用 总被引:2,自引:0,他引:2
为探讨玉米//花生间作系统中玉米根系分泌物对连作花生土壤中酚酸类物质化感作用的影响机制,采用二氯甲烷提取了玉米抽雄期根系分泌物,添加到含有不同浓度的连作花生根系分泌物中主要的三种酚酸类物质(肉桂酸、邻苯二甲酸和对羟基苯甲酸)混合物的土壤中,研究了土壤微生态环境变化情况。结果表明,酚酸类物质对土壤微生物量、微生物活性、酶活性及养分含量均存在化感抑制作用,且浓度越高,抑制作用越强(P<0.05)。整个培养时期,添加玉米根系分泌物均增加了酚酸类物质处理土壤呼吸强度、酶活性、微生物量及养分含量,以低浓度处理增幅较大,分别平均增加7.58%、6.73%、7.72%和4.90%;降低了酚酸类物质对土壤各指标的化感指数,其中低浓度酚酸类物质处理土壤微生物量碳氮、微生物活性、酶活性和养分含量的化感指数分别降低21.57%、21.19%、 26.32%和20.95%。3次取样,酚酸类物质的化感作用呈先增强后降低的趋势,各处理在第10d达到最强;而玉米根系分泌物对酚酸类物质化感作用的影响以处理第5d最强,随后呈减弱趋势。玉米根系分泌物可在一定程度上缓解酚酸类物质对土壤微生态环境的化感作用,为玉米//花生间作缓解花生连作障碍技术提供了理论依据。 相似文献
26.
K. A. Ross D. Ehret D. Godfrey L. Fukumoto M. Diarra 《International Journal of Fruit Science》2017,17(2):202-232
This work examined the processing yields, physico-chemical characteristics, and bioactive properties of Canadian organic cranberry and blueberry pomace and phenolic-enriched extractives. The ethanol extracts from each berry contained three to four times the soluble solids and sugar contents compared to the pomace. The lipid content of organic cranberry pomace (4.44%), cranberry ethanol extractives (3.86%), and blueberry ethanol extractives (4.44%) were significantly lower than the lipid content of the organic blueberry pomace (5.42%). The organic blueberry pomace showed higher protein content (8.41%) than organic cranberry pomace (5.76%); however, both organic cranberry and blueberry ethanol extracts showed similarly low protein contents. Significant differences were observed in the mineral and elemental contents of both pomaces and their extractives. Total phenolics, tartaric esters, flavonols, anthocyanins, and antioxidant activities were increased by two to three times in both organic cranberry and blueberry ethanol extracts compared to their respective pomaces. The major anthocyanins detected in organic blueberry pomace and ethanol extracts were peonidin 3-glucoside, malvidin 3-galactoside, malvidin 3-glucoside, and cyanidin 3-arabinoside. Peonidin 3-galactoside, cyanidin 3-galactoside, cyanidin 3-arabinoside, and peonidin 3-arabinside were the major anthocyanins in the organic cranberry and ethanol extacts. Results indicated that cranberry and blueberry pomace could be used to develop bioactives with antioxidant activity for potential health benefit and/or bioenergy production. 相似文献
27.
钟朝艳 《湖南农业大学学报(自然科学版)》2011,(1):85-88
考虑到保险公司在实际经营中收益所具有的不确定性和分红策略,建立一类具有线性红利界和带随机扰动的双复合Poisson风险模型,利用鞅方法给出模型关于破产概率的一个定理及上界. 相似文献
28.
针对我国北方农村的气候和农艺特点,设计制造出一种多功能复式作业机。详细说明该机的总体结构设计。分析该机作业技术特点,介绍整机主要技术参数和各部装结构形式。并通过进行机组耕整作业试验来验证该复式作业机的作业效果,结果证实该机具设计科学合理,技术性能良好,结构简单,操作方便,性价比合理。 相似文献
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30.
水产品营养价值高,含有多种氨基酸、不饱和脂肪酸、矿物质等营养素而脂肪含量相对较低,深受人们喜爱,也是中国居民膳食指南中的重要组成部分。水产品中由于水分、蛋白质等成分含量丰富,极易在微生物和内源酶的作用下发生蛋白质、脂肪等的降解或氧化而腐败变质,从而缩短了货架期,降低了商业价值。气调包装保鲜技术是指通过使用高阻隔性能的复合包装材料,并调整食品贮藏环境中的气体组成来改善食品贮藏品质并延长货架期的技术,因其安全性高、保鲜效果好而被广泛应用于水产品保鲜领域中,本文总结了近几年气调包装复合其他保鲜技术(低温、紫外杀菌、臭氧处理、超高压处理、化学保鲜剂、生物保鲜剂)在水产品保鲜领域中的应用,旨在为气调包装在水产品保鲜中的进一步应用提供理论依据。已有的研究表明该复合技术能有效地降低水产品贮藏末期微生物总数、挥发性盐基氮、三甲胺、生物胺等指标,并维持较高的感官评分、水分含量、鲜度值,可有效延长水产品的货架期,未来可以从气调包装复合保鲜技术的抑菌机理、理化指标变化机理、包装材料及模式等方面展开深入研究。 相似文献