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Food intake rate and delivery strategy in aquaculture
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作者 游奎 马彩华 +4 位作者 高会旺 李凤岐 张美昭 邱彦涛 王波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期263-267,共5页
In aquaculture,it is important to estimate in advance how much food cultured animals would take.The rate of food consumption by cultured animals to available food amount is defined as the food intake rate(FIR) in this... In aquaculture,it is important to estimate in advance how much food cultured animals would take.The rate of food consumption by cultured animals to available food amount is defined as the food intake rate(FIR) in this paper.To some extents,FIR reflects the quality of food,the health of cultured animals and the delivery efficiency.In practice,it is difficult to estimate in advance the accurate quantity of food that cultured animal needs.Usually,food is provided more than the need by animals,causing excess food that may pollute water and environment.Our experiments in past years show that FIR at 80% is recommended. 展开更多
关键词 food intake rate (FIR) water quality AQUICULTURE
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Relationship Between Rate of Intake and Daily Intake of Dry,Mature Subterranean Clovers by Sheep
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《畜牧与饲料科学》 1997年第S1期161-172,共2页
关键词 Relationship Between rate of intake and Daily intake of Dry Mature Subterranean Figure Clovers by Sheep
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Effects of Addition of Lactobacillus plantarum and Enterococcus faecium Inoculants to High-Nitrogen Fertilized Timothy (Phleum pratense L.) on Fermentation, Nutritive Value, and Feed Intake of Silage
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作者 Peng Wang Kousaku Souma +6 位作者 Hideki Okamoto Tatsunori Yano Masayuki Nakano Akihiro Furudate Chihiro Sato Jiabao Zhang Takayoshi Masuko 《American Journal of Plant Sciences》 2014年第26期3889-3897,共9页
The objective of this study was to examine the effects of addition of inoculant to high-nitrogen (N) fertilized timothy on fermentation, nutritive value, and feed intake of silage. The silage of timothy cultivated wit... The objective of this study was to examine the effects of addition of inoculant to high-nitrogen (N) fertilized timothy on fermentation, nutritive value, and feed intake of silage. The silage of timothy cultivated with a N fertilizer rate at two levels (high level (H), standard level (S)) was prepared with (SI, HI) or without (SC, HC) an inoculants. The CP content of H increased by 38 g&middotkg-1 DM compared with that of S, and the WSC and ADF contents decreased compared with those of S. Regarding the fermentation of silage, the pH and NH3-N ratio was significantly lower in the silage with inoculant (SI and HI), showing improvement of the fermentation compared with those of the silage without the addition (SC and HC). The CP content was significantly higher in HC and HI than in SC and SI, and the NDF content was the lowest in HI among the four treatments. The CP digestibility of HC and HI was significantly higher than those of SC and SI. The EE digestibility of SI was significantly higher than that of SC, and that of HI was significantly higher than that of HC. The DCP contents were significantly higher in HC and HI than in SC and SI. The TDN content was the lowest in SC and highest in HI. The DCP intakes of HC and HI were significantly higher than those of SC and SI. When the N fertilizer rate was increased, the DCP content and DCP intake of the silage increased, and the addition of inoculant improved the fermentation and increased the TDN content. 展开更多
关键词 DCP intake FERMENTATION High-Nitrogen Fertilizer rate Lactobacillus plantarum TIMOTHY SILAGE
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进气道滚流比对发动机压升率及噪声的影响
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作者 赵磊 纪雷 +3 位作者 赵铮 关昊 杨敏敏 李东辉 《内燃机与动力装置》 2024年第3期51-56,共6页
以某双喷射6缸发动机为研究对象,设计高滚流比和低滚流比2种进气道,通过三维计算流体动力学软件AVL Fire对缸内流场进行仿真,分析发动机燃烧特性,并进行台架燃烧测试和噪声测试。仿真结果表明:在转速为2800 r/min、平均有效压力为1.3 MP... 以某双喷射6缸发动机为研究对象,设计高滚流比和低滚流比2种进气道,通过三维计算流体动力学软件AVL Fire对缸内流场进行仿真,分析发动机燃烧特性,并进行台架燃烧测试和噪声测试。仿真结果表明:在转速为2800 r/min、平均有效压力为1.3 MPa工况下,相比高滚流进气道方案,低滚流气道方案的缸内第一、二个峰值滚流比分别降低了43.3%、34.9%,最大缸内平均压力降低544 kPa,最大压力升高率降低16.84%。台架试验结果表明:2种进气道的燃烧持续期相差不大,相比高滚流进气道方案,低滚流方案以曲轴转角表示的燃烧重心推迟了2.02°,燃油消耗率增大0.67%,压力升高率(压升率)降低了19.87%,发动机在频率为700~1300 Hz时的噪声约降低6.0 dB,噪声改善效果明显。 展开更多
关键词 进气道 滚流比 仿真分析 压升率 噪声
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食物氮含量改变对飞蝗取食、营养利用及生长速率的影响
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作者 马桂平 季荣 +5 位作者 何岚 张永军 郭雅婷 林峻 董化楠 陈妍 《昆虫学报》 CAS CSCD 北大核心 2024年第5期659-665,共7页
【目的】食物氮含量改变对昆虫的影响是预测害虫种群变化趋势的重要内容。本研究旨在探究食物氮含量改变对飞蝗Locusta migratoria取食、营养利用及生长速率的影响。【方法】以氮含量为1.0%,2.5%,4.0%,5.5%和7.0%的食物分别饲喂飞蝗3龄... 【目的】食物氮含量改变对昆虫的影响是预测害虫种群变化趋势的重要内容。本研究旨在探究食物氮含量改变对飞蝗Locusta migratoria取食、营养利用及生长速率的影响。【方法】以氮含量为1.0%,2.5%,4.0%,5.5%和7.0%的食物分别饲喂飞蝗3龄雌、雄蝗蝻,每日收集剩余粪便和食物残渣并烘干后称重,计算取食量、生长速率及营养利用指标。【结果】1.0%氮含量食物组飞蝗3龄蝗蝻取食量最大,雌、雄虫取食量分别为0.2559和0.2326 g;7.0%氮含量食物组取食量最小,雌、雄3龄蝗蝻取食量分别为0.0944和0.0766 g。随着食物氮含量增加,飞蝗雌、雄蝗蝻取食量显著下降,但是近似消化率、食物利用率和食物转化率显著增加。雌蝗蝻生长速率在2.5%氮含量食物组最高。【结论】飞蝗蝗蝻取食低氮食物时可以通过增加取食量补偿氮。 展开更多
关键词 飞蝗 取食量 营养利用 生长速率
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中国十五省(区、市)18~64岁居民鱼虾类食物摄入状况分析
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作者 崔少颖 黄聪慧 +4 位作者 杨云淇 贾小芳 杜文雯 苏畅 王惠君 《中国食物与营养》 2024年第10期84-88,共5页
目的:分析中国成年居民鱼虾类食物摄入状况。方法:数据来自2018年“中国健康与营养调查”项目。将具有完整连续3d24h膳食数据和人口经济特征数据的18~64岁居民作为研究对象,分析其鱼虾类食物消费率和摄入量,并与《中国居民膳食指南(2022... 目的:分析中国成年居民鱼虾类食物摄入状况。方法:数据来自2018年“中国健康与营养调查”项目。将具有完整连续3d24h膳食数据和人口经济特征数据的18~64岁居民作为研究对象,分析其鱼虾类食物消费率和摄入量,并与《中国居民膳食指南(2022版)》鱼虾类食物推荐摄入量进行比较。结果:我国十五省(区、市)18~64岁居民2018年鱼虾类食物的消费率为41.9%、日均摄入量为28.5g、摄入量未达到推荐摄入量的人群比例为87.0%。不同受教育程度、居住地区和家庭人均年收入水平的成年居民鱼虾类食物消费率和消费量存在显著差异。结论:我国十五省(区、市)18~64岁居民鱼虾类食物消费率仍较低,摄入量也远未达到鱼虾类推荐摄入量,应进一步对我国成年居民开展营养宣教,提高鱼虾类食物的消费水平。 展开更多
关键词 鱼虾类食物 成人 消费率 消费量
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某轻型柴油机进气门油封结构优化设计
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作者 闫福永 胡琦山 +1 位作者 齐伟 王有治 《内燃机与配件》 2024年第1期35-37,共3页
进气门油封泄漏率是影响气门积碳的主要因素之一。经过对进气门油封结构研究,提出一种解决气门积碳的低泄漏率进气门油封结构。通过气门油封泄漏率试验和耐久试验验证,并对比试验前后的进气门杆直径变化量和进气门下沉变化量,结果表明,... 进气门油封泄漏率是影响气门积碳的主要因素之一。经过对进气门油封结构研究,提出一种解决气门积碳的低泄漏率进气门油封结构。通过气门油封泄漏率试验和耐久试验验证,并对比试验前后的进气门杆直径变化量和进气门下沉变化量,结果表明,优化后的进气门油封在保证气门、座圈导管等相关配副磨损可接受的前提下,能够实现降低气门积碳的效果。研究结果可以为气门积碳的解决提供参考。 展开更多
关键词 进气门油封 泄漏率 气门积碳
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基于燃油经济性的Atkinson循环发动机优化设计研究
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作者 陈小强 赵欣 《河南科技》 2024年第16期41-45,共5页
[目的]将传统Otto循环发动机改型设计为混合动力Atkinson循环发动机,以提高发动机燃油经济性。[方法]以某Otto循环发动机为原型机,建立发动机GT-power仿真模型,通过提高发动机压缩比,增大进气凸轮工作包角,将原机仿真模型改型为Atkinso... [目的]将传统Otto循环发动机改型设计为混合动力Atkinson循环发动机,以提高发动机燃油经济性。[方法]以某Otto循环发动机为原型机,建立发动机GT-power仿真模型,通过提高发动机压缩比,增大进气凸轮工作包角,将原机仿真模型改型为Atkinson循环发动机仿真模型。利用Atkinson循环发动机仿真模型对发动机进气凸轮工作包角、进气门关闭时刻和排气门关闭时刻进行优化分析,确定最佳参数。[结果]Atkinson循环发动机在外特性工况下扭矩有所下降,燃油消耗率最高降低了7.2%;最低燃油消耗率由原型机的244 g/kW·h降至235 g/kW·h,低油耗区域转速范围增大。[结论]试验结果显示,优化后的Atkinson循环发动机燃油经济性得到了改善,满足混合动力汽车对发动机的工作需求,证明了优化设计方法的可行性。 展开更多
关键词 Atkinson循环 进气门关闭时刻 燃油消耗率
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不同体位护理在早产儿中的应用效果
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作者 于新月 《妇儿健康导刊》 2024年第19期119-122,共4页
目的探讨不同体位护理在早产儿中的应用效果。方法选取江苏省昆山市第一人民医院2022年6月至2023年6月收治的70例早产儿为研究对象,按照随机数字表法分为对照组和观察组,各35例。对照组给予常规仰卧体位,观察组给予自由体位,比较两组心... 目的探讨不同体位护理在早产儿中的应用效果。方法选取江苏省昆山市第一人民医院2022年6月至2023年6月收治的70例早产儿为研究对象,按照随机数字表法分为对照组和观察组,各35例。对照组给予常规仰卧体位,观察组给予自由体位,比较两组心率、呼吸频率及每日睡眠时间、每日进奶增长量。结果护理后第3天、第7天观察组心率、呼吸频率低于对照组,每日睡眠时间长于对照组,每日进奶增长量多于对照组(P<0.05)。结论早产儿应用自由体位能够改善心率、呼吸频率、睡眠时间及进奶量。 展开更多
关键词 早产儿 自由体位 心率 呼吸频率 睡眠时间 进奶量
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切向入流旋流竖井在深圳市前海-南山排水深层隧道中的应用研究
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作者 黄春华 邢方亮 王斌 《中国农村水利水电》 北大核心 2024年第2期74-82,90,共10页
为探究切向入流旋流竖井的水力特性,采用物理模型手段,结合深圳市前海-南山排水深层隧道中郑宝坑渠旋流竖井方案,研究旋流竖井内的水流流态、消能特性、排气效果及特征压力值。结果表明:各工况下进口位置处水流逐渐形成水翅,进入竖井后... 为探究切向入流旋流竖井的水力特性,采用物理模型手段,结合深圳市前海-南山排水深层隧道中郑宝坑渠旋流竖井方案,研究旋流竖井内的水流流态、消能特性、排气效果及特征压力值。结果表明:各工况下进口位置处水流逐渐形成水翅,进入竖井后沿内壁形成螺旋跌落流,水流流态较好,当竖井流量极小时竖井内无法形成螺旋跌落流,水流进入竖井后呈射流形态跌落至竖井底部;旋流竖井总消能率在81.9%~89.5%之间,消能率随着流量的增大而逐步减小;旋流竖井相对于传统水工旋流竖井,具有消能效果好、结构简单等优点,在城市深层排水系统中具有较大的应用空间。 展开更多
关键词 切向入口 旋流竖井 深层隧道 消能率
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进气涡流对船用中速柴油机的性能影响
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作者 朱涛 朱娜 和晓锋 《柴油机》 2024年第6期6-11,25,共7页
以某船用中速柴油机为研究对象,通过在气缸盖底面进气门座圈处增加不同的偏心倒角,获得不同进气涡流比和流量系数的组合。利用一维和三维仿真计算,研究不同组合对柴油机燃油消耗率、碳烟和NOx排放的影响,并通过试验对比验证。计算和试... 以某船用中速柴油机为研究对象,通过在气缸盖底面进气门座圈处增加不同的偏心倒角,获得不同进气涡流比和流量系数的组合。利用一维和三维仿真计算,研究不同组合对柴油机燃油消耗率、碳烟和NOx排放的影响,并通过试验对比验证。计算和试验结果均表明涡流比对该柴油机高、低工况性能的影响截然不同。最终选取不同的涡流比和流量系数组合方案,分别应用到不同的细分市场,以满足不同的性能需求。 展开更多
关键词 船用中速柴油机 进气涡流比 流量系数 燃油消耗率 排放
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营养素及能量摄入指导对妊娠糖尿病患者血糖控制及病情预防价值
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作者 郭玉英 《中华养生保健》 2024年第1期12-15,共4页
目的探究营养素及能量摄入指导对妊娠糖尿病孕妇血糖控制及病情预防的临床价值。方法选择2020年3月—2022年4月于青海省大通县第二人民医院被确诊为妊娠糖尿病的80例孕妇为研究对象,将2020年3月—2021年2月未实施营养指导的40例孕妇设... 目的探究营养素及能量摄入指导对妊娠糖尿病孕妇血糖控制及病情预防的临床价值。方法选择2020年3月—2022年4月于青海省大通县第二人民医院被确诊为妊娠糖尿病的80例孕妇为研究对象,将2020年3月—2021年2月未实施营养指导的40例孕妇设为对照组,将2021年3月—2022年4月实施营养指导的40例孕妇设为研究组,对比两组孕妇干预前后身体质量指数(BMI)、体质量增长量及空腹血糖、餐后2 h血糖、分娩前糖化血红蛋白水平差异,对比两组孕妇血糖控制合格率、尿酮体阳性率、妊娠结局及并发症发生情况差异。结果干预前两组孕妇BMI比较,差异无统计学意义(P>0.05);干预后研究组BMI低于对照组,差异有统计学意义(P<0.05);同时研究组体质量增长量低于对照组,差异有统计学意义(P<0.05)。干预前两组孕妇的空腹血糖、餐后2 h血糖、糖化血红蛋白水平比较,差异无统计学意义(P>0.05);干预后两组孕妇的空腹血糖、餐后2 h血糖、糖化血红蛋白水平均降低,且研究组孕妇空腹血糖、餐后2 h血糖、糖化血红蛋白水平均低于对照组,差异有统计学意义(P<0.05)。研究组孕妇血糖控制合格率明显高于对照组,差异有统计学意义(P<0.05);两组尿酮体阳性率比较,差异无统计学意义(P>0.05)。研究组巨大儿发生率低于对照组,差异有统计学意义(P<0.05),两组早产、剖宫产、湿肺及肺炎等的发生率比较,差异无统计学意义(P>0.05)。研究组孕妇产后出血、产程停滞、胎儿窘迫等并发症总发生率显著低于对照组,差异有统计学意义(P<0.05)。结论对妊娠糖尿病产妇开展营养素及能量摄入指导有助于控制孕妇体质量,提高孕妇血糖控制合格率,同时一定程度上还可以降低孕妇围产期并发症发生率,具有一定的应用运用价值。 展开更多
关键词 营养素 能量摄入 妊娠期糖尿病 体质量 血糖合格率 围产期并发症
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Energy intake, oxidative stress and antioxidant in mice during lactation
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作者 Guo-Xiao ZHENG Jiang-Tao LIN +2 位作者 Wei-Hong ZHENG Jing CAO Zhi-Jun ZHAO 《Zoological Research》 CAS CSCD 2015年第2期95-102,共8页
Reproduction is the highest energy demand period for small mammals, during which both energy intake and expenditure are increased to cope with elevated energy requirements of offspring growth and somatic protection. O... Reproduction is the highest energy demand period for small mammals, during which both energy intake and expenditure are increased to cope with elevated energy requirements of offspring growth and somatic protection. Oxidative stress life history theory proposed that reactive oxygen species(ROS) were produced in direct proportion to metabolic rate, resulting in oxidative stress and damage to macromolecules. In the present study, several markers of oxidative stress and antioxidants activities were examined in brain, liver, kidneys, skeletal muscle and small intestine in non-lactating(Non-Lac) and lactating(Lac) KM mice. Uncoupling protein(ucps) gene expression was examined in brain, liver and muscle. During peak lactation, gross energy intake was 254% higher in Lac mice than in Non-Lac mice. Levels of H2O2 of Lac mice were 17.7% higher in brain(P〈0.05), but 21.1%(P〈0.01) and 14.5%(P〈0.05) lower in liver and small intestine than that of Non-Lac mice. Malonadialdehyde(MDA) levels of Lac mice were significantly higher in brain, but lower in liver, kidneys, muscle and small intestine than that of Non-Lac mice. Activity of glutathione peroxidase(GSH-PX) was significantly decreased in brain and liver in the Lac group compared with that in the Non-Lac group. Total antioxidant capacity(TAOC) activity of Lac mice was significantly higher in muscle, but lower in kidneys than Non-Lac mice. Ucp4 and ucp5 gene expression of brain was 394% and 577% higher in Lac mice than in Non-Lac mice. These findings suggest that KM mice show tissuedependent changes in both oxidative stress and antioxidants. Activities of antioxidants may be regulated physiologically in response to the elevated ROS production in several tissues during peak lactation. Regulations of brain ucp4 and ucp5 gene expression may be involved in the prevention of oxidative damage to the tissue. 展开更多
关键词 ANTIOXIDANT Energy intake LACTATION Metabolic rate Oxidative stress Uncoupling protein
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Effects of Organic Substrates on Development and Survival of Blattela germanica for Food and Feed in Kenya
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作者 Victor Muhumbwa Ngaira Reuben Oyoo Mosi +2 位作者 Caroline Celine Wambui Francis Obuoro Wayua Ann Mumbi Wachira 《Open Journal of Animal Sciences》 CAS 2022年第3期484-492,共9页
Entomophagy has gained popularity as a novel approach to addressing food and nutrition insecurity, particularly in sub-tropical and tropical countries. Cockroaches, for example, have the potential to alleviate nutriti... Entomophagy has gained popularity as a novel approach to addressing food and nutrition insecurity, particularly in sub-tropical and tropical countries. Cockroaches, for example, have the potential to alleviate nutritional deficiencies, as well as the erratic supply of protein in feeds. They can also be reared on locally available organic substrates. This study investigated growth performance and survival of german cockroach (Blattella germanica) reared on locally available organic matter substrates as treatments;spent brewers’ grain (Treatment A), Treatment B consisting of (40%: wheat bran: 40% spent brewers’ grain: 20% Caridina nilotica), wheat bran (Treatment C), and C. nilotica (Treatment D) and in a completely randomised design (CRD). Each treatment was replicated four times, while in each replicate 20 - 30 nymphs were reared for forty-two days. Feed intake for all the treatments was not significantly different. There was a significant difference (P 0.05) in mature weight, average daily weight gain, live weight, and survival during rearing period. Cockroach performed well on treatment B and recorded highest mature weight, overall performance index, survival was 90.25 mg, 197.35, 96%. The least perfomance was reported in Treatment C;1.78, 83, 143.17 and 72.5 for average growth rate, survival, overall perfomance and mature weight respectively. B. Based on these findings, a single feed as used in this study was inferior to the composite (Treatment B) in all parameters of growth performance and survival. The composite diet (Treatment B) could be suitable substrate for mass production of B. germanica for feed and food. 展开更多
关键词 COCKROACH Feed intake Growth rate
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管道式微孔增氧装置的增氧性能研究 被引量:1
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作者 管崇武 单建军 +2 位作者 宋红桥 吴凡 陈石 《渔业现代化》 CSCD 2023年第2期25-31,共7页
为了评价不同进气量和进气压力对管道式微孔增氧装置增氧性能的影响,参照SC/T 6051—2011《溶氧装置性能试验方法》中的标准测试方法,在3个进气压力条件下开展不同进气量的室内清水增氧试验。结果显示:在相同进气量条件下,降低进气压力... 为了评价不同进气量和进气压力对管道式微孔增氧装置增氧性能的影响,参照SC/T 6051—2011《溶氧装置性能试验方法》中的标准测试方法,在3个进气压力条件下开展不同进气量的室内清水增氧试验。结果显示:在相同进气量条件下,降低进气压力可取得较好的增氧性能;在相同进气压力条件下,装置的氧质量转移系数和增氧能力随着进气量增大而增大,氧利用率和动力效率则呈下降趋势,但在进气压力为0.2 MPa时,其氧利用率和动力效率下降幅度较缓。综合考虑增氧能力和运行能耗等因素,装置的进气参数可设置为进气压力0.2 MPa、进气量0.064~0.081m^(3)/h,在该条件下增氧能力达到29.79~34.36 g/h,氧利用率达到29.83%~32.32%,动力效率达到7.67~8.31 kg/(kW·h)。研究表明,进气量对装置的增氧性能有较大的影响,合理控制进气量对于提高增氧性能、降低增氧装置能耗具有重要意义。 展开更多
关键词 管道式微孔增氧装置 增氧性能 进气量 氧利用率 循环水养殖
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宁都黄鸡新品系剩余采食量与生产性能的相关性分析 被引量:1
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作者 魏岳 唐维国 +5 位作者 刘林秀 康昭风 武艳平 张危红 谢金防 陈荣俊 《江西农业学报》 CAS 2023年第10期74-79,共6页
以宁都黄鸡培育的新品系(A系和E系)为研究对象,分别选取了42~56日龄和84~98日龄2个生长阶段,测定其剩余采食量、日平均采食量、体增重等指标并分析了其遗传参数。结果显示,2个品系的剩余采食量、代谢体重、平均日增重等指标均呈极显著... 以宁都黄鸡培育的新品系(A系和E系)为研究对象,分别选取了42~56日龄和84~98日龄2个生长阶段,测定其剩余采食量、日平均采食量、体增重等指标并分析了其遗传参数。结果显示,2个品系的剩余采食量、代谢体重、平均日增重等指标均呈极显著或显著差异;2个品系的剩余采食量均表现为中度遗传力,并且与饲料转化率和日平均采食量呈正遗传相关(ra>0.30),而与代谢体重和平均日增重呈负遗传相关。剩余采食量对于宁都黄鸡新品系屠体性状有着显著的相关性,总体表现为选择剩余采食量将有利于屠体性状的提高。研究结果表明,剩余采食量和生长性状相互独立,将剩余采食量作为选择性状,在不影响生长性状的基础上,更有利于提高宁都黄鸡2个品系的饲料转化效率,同时可以用于间接选择屠体性状,对宁都黄鸡的平衡育种具有重要的指导意义。 展开更多
关键词 宁都黄鸡 剩余采食量 生长性能 饲料转化率
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Feeding Behavior, Body Weight and Growth Rate during Post-Deprivation Period in Rats
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作者 Antonio López-Espinoza Alma Gabriela Martínez Moreno +6 位作者 Virginia Gabriela Aguilera Cervantes Elia Valdé s Miramontes Luis Alfonso Mojica Contreras Monica Navarro-Meza Claudia Patricia Beltrán-Miranda Ana Cristina Espinoza-Gallardo 《Food and Nutrition Sciences》 2015年第14期1307-1315,共9页
Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The ... Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The aim of this study was to evaluate the deprivation effect on feeding pattern, growth rate and body weight during post-deprivation. Sixteen albino rats (3 months old at the beginning of the experiment) were exposed to 72-hour total food deprivation every 15 days. Food and water were freely available during non-deprivation periods. Rats completed three cycles comprised by a free access period followed by food deprivation. Once deprivation was removed, food and water consumption increased and then decreased, while body weight was recovered. Growth rate increased after every deprivation period and reached similar levels to those presented by the control group. Depriving rats from one commodity (i.e., food) cause them to restrain their consumption of the other freely available commodity (i.e., water). Results confirm that food deprivation modifies growth rate, water and food consumption. Additionally, during post-deprivation period, differences between males and females were not registered. 展开更多
关键词 Body WEIGHT FOOD intakE Water intakE Post-Deprivation PERIOD Growth rate
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哺乳母猪智能饲喂系统设计与试验
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作者 吕恩利 陈高峰 +3 位作者 夏晶晶 王飞仁 吴凡 曾志雄 《中国农机化学报》 北大核心 2023年第7期154-162,共9页
为实现哺乳母猪智能饲喂、人机交互友好和易检修,设计一套包括智能饲喂器、手持终端PDA、中央控制器和CAN-Bus总线的哺乳母猪智能精准饲喂系统,可在现场方便进行猪只出入栏管理、猪只状态动态监测、异常情况实时报警功能。在云南省某规... 为实现哺乳母猪智能饲喂、人机交互友好和易检修,设计一套包括智能饲喂器、手持终端PDA、中央控制器和CAN-Bus总线的哺乳母猪智能精准饲喂系统,可在现场方便进行猪只出入栏管理、猪只状态动态监测、异常情况实时报警功能。在云南省某规模化母猪场安装280台哺乳母猪智能饲喂器,与配置传统饲喂的生产线进行生产性能对比试验。试验结果表明,智能饲喂实现人机交互友好、触碰下料、智能湿拌、无接触操作和易检修的特点。智能饲喂较传统饲喂相比,可提高母猪平均日采食量0.673 kg,日饲料浪费量减少0.345 kg,智能饲喂和传统饲喂不同日龄的平均日采食量和日饲料浪费量存在极显著差异(P<0.01);月产健仔数提高10.44%,窝均健仔数增加0.69头,21天断奶仔猪均重增加0.370 kg;哺乳母猪背膘损失降低34.43%,7天断配率提高4%。对系统进行投资回报率分析,智能饲喂能有效减少饲料浪费,提高生产成绩,投资回报率高,可有效助力规模化猪场降本增效。该研究对母猪智能饲喂系统的开发和应用提供参考。 展开更多
关键词 哺乳母猪 智能饲喂 生产性能 采食量 断配率
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Comparison between Fast Fourier Transform and Autoregressive Model on Analysis of Autonomic Nervous Function after Food Intake in Women
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作者 Kumiko Ohara Yoshimitsu Okita +1 位作者 Katsuyasu Kouda Harunobu Nakamura 《Health》 CAS 2016年第6期567-574,共8页
Purpose: Heart rate variability (HRV) is acknowledged as a useful tool to estimate autonomic function. Fast Fourier transform (FFT) and autoregressive model (AR) are used for power spectral analysis of HRV. However, t... Purpose: Heart rate variability (HRV) is acknowledged as a useful tool to estimate autonomic function. Fast Fourier transform (FFT) and autoregressive model (AR) are used for power spectral analysis of HRV. However, there is little evidence of agreement between FFT and AR in relation to HRV following food intake in females. In the present study, we applied both FFT and AR after food intake during the follicular and luteal phases, and compared raw low-frequency (LF) and high- frequency (HF) powers, and LF/HF ratio obtained with the two power-spectral analytical methods. Methods: All subjects participated in two sessions: follicular phase session and luteal phase session. In each session, R-R intervals were continuously recorded before and after meals, and power spectral analysis of heart rate variability was performed. We analyzed low-frequency power (LF: 0.04 - 0.15 Hz) and high-frequency power (HF: 0.15 - 0.40 Hz) by using FFT and AR. LF and HF power were computed for each 30 sec, 1 min, 2.5 min, and 5 min of the 5-min R-R data before meal intake and at 20, 40, 60 and 80 min after meal intake. The LF/HF ratio was calculated as an index of sympathovagal balance. Results: In the present study, after 30 sec and 1 min of segment analysis, there was little interchangeability between AR and FFT in LF, HF, and LF/HF ratio in both follicular and luteal phases. In 2.5 min or 5 min of segment analysis, there was interchangeability between FFT and AR in LF and HF, but not in the LF/HF ratio in both follicular and luteal phases. Additionally, FFT underestimated HRV compared with AR, and the extent of underestimation increased with increasing AR value. Conclusion: FFT underestimated HRV compared with AR, and FFT correlated poorly with AR when the analysis segment was shortened. 展开更多
关键词 Heart rate Variability Power Spectral Analysis Food intake Females Menstrual Cycle
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过瘤胃辣椒油树脂对夏季奶牛产奶量、干物质采食量、呼吸频率和血清生化指标的影响 被引量:1
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作者 赵阳 宋懿峰 +5 位作者 苏少晖 王园 安晓萍 齐景伟 韩森 高欣 《黑龙江畜牧兽医》 CAS 北大核心 2023年第5期87-93,137,共8页
为了研究过瘤胃辣椒油树脂对夏季奶牛产奶量、干物质采食量、呼吸频率和血清生化指标的影响,试验将465头胎次为(2.5±1.3)胎、泌乳天数为(109.0±52.3)d的中国荷斯坦奶牛随机分为2组,每组2个重复,对照组(236头)每个重复118头,... 为了研究过瘤胃辣椒油树脂对夏季奶牛产奶量、干物质采食量、呼吸频率和血清生化指标的影响,试验将465头胎次为(2.5±1.3)胎、泌乳天数为(109.0±52.3)d的中国荷斯坦奶牛随机分为2组,每组2个重复,对照组(236头)每个重复118头,试验组(229头)2个重复分别为114头和115头。对照组饲喂全混合日粮(TMR),试验组每头奶牛每天饲喂添加300 mg的过瘤胃辣椒油树脂的TMR。试验期为91 d,分为试验前期(1~30 d)、中期(31~60 d)和后期(61~91 d)三个阶段。试验期间,每天09:00、15:30使用手持温湿度计测定距地面1.8 m处环境温度、相对湿度,计算温湿度指数;每天早晨投料后采集TMR样品,测定各组的干物质采食量,同时记录每天每头奶牛的产奶量和呼吸频率;于正试期第30,60,91天采血,检测血清生化指标;应用Broken-stick回归模型分析温湿度指数与呼吸频率的关系。结果表明:试验期内共有62 d的温湿度指数>72试验前期、中期和后期平均温湿度指数分别为70.61±4.02、75.60±2.84、73.17±2.33,温湿度指数>72分别有11,27,24 d;试验后期奶牛产奶量显著低于试验前期(P<0.05),试验组奶牛试验前、后期产奶量和干物质采食量均显著高于对照组(P<0.05);试验中期奶牛呼吸频率显著高于试验前、后期(P<0.05),试验组奶牛试验前期呼吸频率显著低于对照组(P<0.05),奶牛呼吸频率的温湿度指数阈值由对照组72.13提高至试验组73.27;试验阶段显著影响奶牛血清葡萄糖(GLU)浓度(P<0.05),试验组奶牛试验前期血清ALP活性显著高于对照组(P<0.05),对照组奶牛试验后期血清低密度脂蛋白(LDL)和总胆固醇(CHO)浓度高于试验前期(P<0.05),试验组奶牛试验后期血清LDL浓度显著低于对照组(P<0.05)。说明日粮中添加300 mg/(d·头)的过瘤胃辣椒油树脂能够提高奶牛产奶量和干物质采食量,降低奶牛呼吸频率,提高呼吸频率的温湿度指数阈值,改善血清生化指标,在一定程度上缓解热应激,有益于奶牛的健康养殖。 展开更多
关键词 过瘤胃辣椒油树脂 热应激 产奶量 干物质采食量 呼吸频率 血清生化指标
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