莲藕食根金花虫成虫活动行为的日节律

【目的】通过莲藕食根金花虫Donacia provostii Fairmaire成虫日活动行为节律的系统研究,以期为构建该虫的高效防控技术体系提供科学依据。【方法】采用室外单头隔离和雌雄配对饲养,将莲藕食根金花虫成虫的行为划分为离水静息、触水静息、取食、移动、交配和产卵6个类型,每30 min观察记录一次其活动行为,连续5 d,统计分析其活动行为的日节律。【结果】在时间上,莲藕食根金花虫成虫各行为在各时间点间和时间段间均存在极显著差异(P<0.001);在空间上,成虫各行为在不同位置发生的比例存在极显著差异(P<0.001)、且荇菜叶上和水面的各行为在不同时间点间存在极显著差异(P<0.001)。【结论】莲藕食根金花虫成虫活动行为存在时空上的差异,空间对其行为的影响较时间明显。     

人工光暗条件下花绒寄甲成虫活动行为节律

【目的】花绒寄甲 Dastarcus helophoroides (Fairmaire)是林木蛀干害虫重要的天敌昆虫,研究其行为活动昼夜节律,可以深入了解该虫的生物学特性、阐明其生活习性。【方法】采用室内（温度27±1℃、相对湿度65%±10%）条件下雌雄单头隔离饲养的方法,将该虫的行为活动分为移动、取食、饮水、木块处静息和木块外静息5种行为,每隔30 min记录一次,于2014年7月10-15日连续进行观察。【结果】移动和木块处静息行为存在明显的昼夜节律;移动行为主要发生在暗期,移动高峰发生在20:30-22:30和2:00-4:00之间,而在光期的6:00-16:30之间移动行为发生较少木块处静息行为主要发生在光期的9:30-16:30和暗期的0:00-1:30之间,而在20:30-23:00 的暗期中木块处静息行为发生较少。一天内,该虫发生取食和饮水行为均较少,两类行为主要发生在0:00-14:00之间。木块外静息行为主要发生在暗期的0:30-3:30和20:00-22:00之间。雌、雄成虫的各行为出现的时间和发生百分率无显著差异。【结论】花绒寄甲成虫活动行为受到光、暗条件的显著影响,移动行为主要发生在暗期,而各活动行为在雌、雄虫之间无显著性差异。     

韭菜迟眼蕈蚊成虫行为活动昼夜节律

【目的】本研究旨在明确韭菜迟眼蕈蚊Bradysia cellarum成虫行为活动的昼夜节律,为其室内饲养、行为学研究和研发精准、高效的监测与防控新技术提供依据。【方法】室内系统观察记录了韭菜迟眼蕈蚊成虫羽化盛期求偶、交配、产卵、移动与静息等行为的昼夜节律,分析了其特定行为的时间分配特征。【结果】韭菜迟眼蕈蚊成虫的运动行为和静息行为白天和黑夜均有发生,夜间的繁殖行为(求偶、交配和产卵)频次高于白天的,各时间点的移动、静息和繁殖行为频次占比间均具有显著性差异。韭菜迟眼蕈蚊雌雄成虫的求偶节律相同,一天中求偶有两次高峰,分别出现在3:00和7:00。韭菜迟眼蕈蚊雌雄成虫的交配节律与雌成虫的产卵节律相似,雄成虫移动行为频次占比的峰值时刻均出现在3:00时,雌成虫移动行为频次占比的峰值时刻则出现在19:00时。雌雄成虫静息行为的频次占比均无明显昼夜节律高峰。在日时间分配上,雌、雄成虫以静息行为的时间占比最多,分别为89.53%和89.90%;求偶行为的时间占比最少,分别为0.56%和0.89%。雌雄成虫各行为的日时间占比差异不显著。【结论】韭菜迟眼蕈蚊成虫的求偶、交配、产卵、移动和静息行为具有明显...     

圈养马来熊行为节律和时间分配的季节变化

2009年3－12月,分春、夏、秋、冬4个季节,采用人工观察和红外摄像记录观察2种方式,对上海动物园的圈养马来熊进行行为学研究。建立的行为谱包括休息、走动、踱步、乞食、采食、爬树、探寻、擦痒、玩耍、追逐、嗅闻、示警、打斗、爬跨、舔阴、交配和排泄,将相关行为合并后归纳成6类,即休息、运动、乞食、刻板、社群和其他行为。马来熊用于休息的时间最多,其次是运动和乞食行为。各行为具有不同程度的季节性差异,运动行为（F=62.748,P<0.001）和社群行为（F=26.041,P<0.001）季节性差异极显著,刻板行为（F=4.667,P<0.05）差异显著,休息行为（F=1.857,P>0.05）和乞食行为（F=1.180,P>0.05）差异不显著。圈养马来熊具有明显的日活动节律,00:00－5:00和20:00－24:00是马来熊的休息高峰,6:00开始活动量增大,8:00－9:00是马来熊的正常进食高峰,同时,运动、乞食、社群等行为逐渐增多,乞食行为集中在运动场10:00－15:00游客多的时段。18:00之后运动逐渐减少,进入休息状态。春夏昼间行为比较,运动和刻板行为（P<0.05）差异显著。年龄因素,春季对休息、运动和刻板行为影响特别显著（P<0.001）,社群和乞食行为的影响显著（P<0.05）,夏季对乞食行为影响特别显著（P<0.001）,运动、刻板和社群行为影响显著（P<0.05）。性别因素,春季对社群行为影响极显著（P<0.001）,休息、乞食和其他行为影响显著（P<0.05）,夏季只对社群行为影响显著（P<0.05）。秋冬间各行为差异不显著,室内和运动场的行为对比表明,刻板和休息多在室内,运动行为多在运动场,室内和运动场秋季的运动行为和社群行为差异显著（P<0.05）,冬季的刻板行为差异极显著（P<0.001）。     

白眼潜鸭秋季行为时间分配及活动节律

2012年7~11月,采用焦点动物取样法和瞬时扫描法,在乌鲁木齐近郊水域白湖,对白眼潜鸭（Aythya nyroca）秋季行为进行实地观察研究。制定出白眼潜鸭行为谱,各种行为有取食、保养、运动、休息、警戒、其他,共6类14种。昼间各行为时间分配依次为取食（56.7%）、运动（13.8%）、保养（11.8%）、休息（11.2%）、警戒（5.1%）、其他（1.4%）。其中取食、休息、运动行为有明显的节律性变化。休息行为以家庭为单位聚集在一起进行,取食行为则分开进行。7~9月份7：00~8：00时、18：00~19：00时休息行为出现峰值,10~11月份8：00~9：00时、17：00~18：00时出现峰值;7~9月份取食行为在8：00~9：00时、17：00~18：00时有明显的峰值,10~11月份在10：00~11：00时和15：00~16：00时出现峰值;7~11月份运动行为均在中午达到峰值。白眼潜鸭7~9月份与10~11月份觅食行为、休息行为和保养行为差异极显著（P<0.01）,运动行为无显著性差异（P >0.05）。迁徙前（10月中旬）,白眼潜鸭有集群现象,数量最多达到37只,10月下旬种群集体迁徙。秋季白眼潜鸭主要时间用于取食,意图为了迁徙或越冬积累能量,集群迁徙有利于种群防御天敌。     

中华秋沙鸭越冬行为时间分配及日活动节律

2007年12月-2008年1月和2008年11-12月,在江西省境内4条主要河流及其支流对中华秋沙鸭(Mergus squamatus)越冬期的各种行为活动节律及时间分配进行了实地调查研究。结果表明:中华秋沙鸭越冬期的主要行为有取食、游泳、理羽、静息、睡眠、游戏、飞行和观察。其中取食、游泳、理羽、静息呈明显的节律性变化,且取食与静息呈相反的节律变化;睡眠、飞行、游戏和观察没有明显的节律性变化。取食在7:00-8:00、10:00-11:00、12:00-13:00有明显的峰值,峰值平均间隔2.3h,其它时段具相近取食频次,且上午高于下午。睡眠和静息下午发生频次明显高于上午,并呈现节律性变化,对应3个取食高峰表现为低频次。行为时间分配如下:取食(46%),游泳(23%),理羽(9%)、静息和睡眠(各占8%)、飞行(4%)、游戏(2%)和观察(0.5%)。越冬期中华秋沙鸭大量时间用于取食,意图是为了积累能量。相关分析表明:取食与睡眠的发生呈显著负相关(R=-0.73,df=8,P0.05);取食与飞行的发生呈显著正相关(R=0.70,df=8,P0.05);理羽与静息的发生呈极显著正相关(R=0.88,df=8,P0.01);其他各种行为之间无显著相关性。     

城市公园中赤腹松鼠的家域特征及昼间活动规律初探

2015年12月至2016年5月,对上海动物园内活动的9只赤腹松鼠进行无线电遥测,应用Homing法进行空间定位,基于最小凸多边形（MCP）和95%固定 核空间（95%Kernel）模型估算城市绿地中赤腹松鼠的家域面积、空间分布特征及个体间的重叠情况,同时记录赤腹松鼠的昼间行为规律。赤腹松鼠 家域面积平均值为12376（MCP）~18146 m²（95%Kernel）,雌雄个体间家域面积无显著差异（Independent-sample test,t= -0.101,P=0.922）。 赤腹松鼠冬季家域面积与春季家域面积间无显著差异（One way ANOVA,MCP：F=3.900,P=0.070;95%FK：F=3.566,P=0.081）。部分赤腹松鼠家域 间存在重叠,冬季重叠指数0.36~0.63,春季重叠指数0.02~0.43。赤腹松鼠的昼间行为以移动（29.4%）、取食（25.1%）和休息行为（24.7%）为主 。在不同季节,赤腹松鼠的取食行为发生显著变化（One way ANOVA,F=119.268,P<0.001）,冬季取食行为发生频率最高（33.3%）,夏季最低 （16.4%）;领域行为在夏（15.8%）、秋（16.2%）季发生频率较高,春季（5.8%）降低（One way ANOVA,F=140.416,P<0.001）。赤腹松鼠昼间 活动呈“U”型分布,主要集中于05:00—08:00和15:00—18:00,休息主要分布于12:00—13:00。     

双委夜蛾成虫主要活动节律和卵孵化节律

[目的]双委夜蛾Athetis dissimilis是近年来在我国农田新发现为害的一种害虫,明确其成虫活动节律和卵的孵化节律,可为其预测预报和防治提供依据.[方法]在温度(25±1)℃、相对湿度70％±5％.光周期14 L:10 D环境条件下,观察双委夜蛾的羽化、取食、交配、产卵等行为.[结果]双委夜蛾雌虫、雄虫羽化主要发生在化蛹后第12天的光期,羽化高峰分别在13:00-17:00和13:00-15:00.取食行为主要发生在羽化后前2d,且在暗期取食的个体数(47.08％)显著多于在光期取食的个体数(26.39％).成虫的交配高峰在羽化后第3天,交配主要在暗期03:00-07:00进行,交配持续时间15-90 min,平均47.33min,以持续30-45 min的个体占比最高,达34.44％.羽化后第5天出现产卵高峰,产卵率达96.67％,产卵主要发生在暗期01:00-05:00.卯产出后第5天集中孵化,孵化率达92.04％,孵化高峰期在17:00-23:00,该时段累计孵化率64.99％.成虫羽化后第2天和第7天移动个体的比率较高,分别为9.72％和10.16％,每天进入暗期后移动率逐渐升高,进入光期后逐渐降低.不同日龄成虫在光期和暗期均出现较高比例的静息个体,前者平均为83.67％,后者平均为64.94％.[结论]双委夜蛾成虫羽化、补充营养、交配、产卵、移动、静息等活动行为的昼夜节律明显,可作为其预测预报及防治的依据.     

鄱阳湖越冬白鹤家庭行为

2012年11月至2013年3月,采用焦点取样法,对在江西鄱阳湖国家级自然保护区内越冬的白鹤(Grus leucogeranus)家庭行为进行了研究。结果表明,以家庭为活动单位的白鹤群,成年白鹤活动时间分配比例为:取食80.9%、警戒10.5%、理羽4.0%、游走3.9%、其他0.7%;越冬早期,成年白鹤游走行为的日节律呈现早、晚高,中午低,低谷在10:30~12:30时;越冬晚期,13:00~14:00时出现明显的取食低谷及警戒、游走和理羽的高峰;而越冬早期、中期的理羽高峰出现在14:00~15:00时;成年白鹤雄性与雌性的活动时间分配比例差异不显著;越冬期早、中、晚三个时期,成年白鹤的警戒(F=3.45,P=0.040)、理羽(F=6.99, P=0.001)及游走(F=7.79, P=0.001)行为比例差异显著。幼鹤活动时间分配比例与成年白鹤差异非常显著。幼鹤活动时间分配比例为:取食66.2%、乞食14.0%、警戒3.7%、理羽5.4%、游走3.6%、其他7.1%。雄性成鹤对幼鹤的喂饲频次呈递减趋势,雌性成鹤对幼鹤的喂饲频次从11月底到12月初呈上升趋势,12月中旬以后呈递减状态。整个越冬期,雄、雌成鹤喂饲幼鹤频次无显著性别差异(P=0.340),但越冬中期(P<0.001)及晚期(P=0.005)表现出极显著差异。随着幼鹤的成长,其活动时间节律发生较大变化;幼鹤取食行为比例明显增加,同时其乞食行为的比例显著减少,警戒行为比例显著增加。本次研究从行为学的角度展示了成年白鹤性别差异、幼鹤的生长过程及成鹤对幼鹤生长的重要性。     

柑橘大实蝇成虫在中国板栗雄花花序上的取食行为

【目的】证实并探明柑橘大实蝇Bactrocera minax成虫在中国板栗Castanea mollissima雄花花序上的取食行为,从而为柑橘大实蝇的非化学防控提供理论依据。【方法】采用录像技术对柑橘大实蝇成虫在中国板栗雄花花序上的行为活动过程进行跟踪观察和分析。【结果】柑橘大实蝇成虫在中国板栗雄花花序上的取食行为分为爬行、取食、梳理和静息4个阶段,成虫的取食行为没有固定次序,除无法从静息阶段直接到取食阶段外,成虫可从爬行、取食、梳理和静息4个阶段中的任一阶段随意转入另一阶段。成虫取食行为各个阶段的频次占比由高到低排列顺序为:爬行取食梳理静息。静息阶段平均耗时显著超过取食、梳理和爬行阶段;取食、梳理和爬行阶段之间的平均耗时无显著差异。柑橘大实蝇雌成虫与雄成虫之间,各个阶段频次占比和平均耗时均无显著差异。【结论】结果证实柑橘大实蝇雌雄成虫在中国板栗雄花花序上存在取食行为。     

Endocrine secretion of prostaglandin F2alpha in cyclic gilts is decreased by intrauterine administration of exogenous oxytocin

When administered systemically, oxytocin (OT) stimulates secretion of uterine prostaglandin F2alpha (PGF2alpha) in swine, but the role of endometrially-derived OT in control of PGF2alpha release is not clear. This study determined the effect of exogenous OT, administered into the uterine lumen of intact cyclic gilts, on PGF2alpha secretion during late diestrus. Intrauterine infusion of 40USP units OT (in 30 ml 0.9% saline) was performed for 30 min (1 ml/min) into each uterine horn between 7:00 and 9:00 h on days 10, 12, 14 and 16 after estrus. Beginning 20 min before infusion, samples of jugular venous blood were drawn at 5-10-min intervals for 140 min for quantification of 13,14-dihydro-15-keto-PGF2alpha (PGFM), the major stable metabolite of PGF2alpha. Progesterone was analyzed in samples collected 0, 60 and 120 min after initiation of OT infusion. Treatment with OT did not alter plasma concentrations of PGFM on days 10 or 12 but decreased (P<0.001) PGFM concentrations for 40 min after onset of infusion on day 16. Concentrations of PGFM also were reduced in the pre-treatment samples on day 14 (P=0.05) and day 16 (P<0.001) in OT-infused gilts. Plasma progesterone declined (P<0.01) between days 10 and 16 in control-infused gilts but did not decline until after day 14 (P<0.001) in gilts infused with OT. These results indicate that when OT is administered into the uterine lumen of pigs during late diestrus, it has an anti-luteolytic effect to reduce endocrine secretion of PGF2alpha and delay the decline in progesterone that occurs during luteolysis.     

Evaluation of the potential role of glufosinate-tolerant rice in integrated pest management programs for rice water weevil (Coleoptera: Curculionidae)

The impact of a herbicide-tolerant rice, Oryza sativa L., variety was assessed for its resistance to rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), and its place in current integrated pest management (IPM) programs. Greenhouse experiments were conducted to evaluate the resistance of a glufosinate-tolerant rice variety and its glufosinate-susceptible parent line Bengal to the rice water weevil in the presence and absence of glufosinate applications. The LC50 dose-response and behavioral effects of glufosinate on adult rice water weevils also were studied. Field studies investigated the impacts of glufosinate-tolerant rice on rice water weevil management in the presence and absence of glufosinate under early and delayed flood conditions. Greenhouse studies demonstrated that in the absence of glufosinate, oviposition was 30% higher on the glufosinate-tolerant rice line than on Bengal rice or on glufosinate-tolerant line treated with recommended rates of commercially formulated glufosinate. Applications of glufosinate to glufosinate-tolerant rice resulted in a 20% reduction in rice water weevil larval densities compared with nontreated glufosinate-tolerant rice. The LC50 of glufosinate against adult rice water weevil was nearly 2 times the concentration recommended for application to glufosinate-tolerant rice. There was no difference in the amount of leaf area consumed by adult rice water weevils on glufosinate-treated and nontreated foliage. The absence of direct toxicity of glufosinate to rice water weevil at recommended glufosinate use rates and lack of behavioral effects suggest that the reduction in rice water weevil densities observed after glufosinate applications resulted from herbicide-induced plant resistance. Field experiments showed that neither rice variety nor herbicide use affected larval densities; however, delaying flood and applying insecticide effectively reduced numbers of rice water weevil larvae.     

小型植保无人机超低量喷雾防治稻水象甲

【目的】通过建立适宜新疆荒漠绿洲特殊生态环境的稻水象甲超低量喷雾技术,为稻水象甲的大面积统防统治提供新型施药技术。【方法】以小型遥控多旋翼植保无人机(UAV)为施药机械,以稻水象甲常规喷雾防效大于90%的药剂为首选药剂,开展了药剂、施药量、助剂以及施药机型的筛选试验。【结果】施药后3、7、14和21 d虫口密度高于防治指标的样地所占比例依次为35.71%、21.43%、35.71%和78.57%。30%氯虫·噻虫嗪187.5 mL·hm~(-2)防效最佳,14 d药效高达93.43%;药后21 d,球孢白僵菌3000 mL·hm~(-2)的防效最高,达84.65%。各药剂施药量与防效呈正相关。此外,UAV喷雾防治稻水象甲时,添加助剂的平均防效可提高22.29%~28.49%。【结论】在农业精准施药、绿色生产中,综合考虑供试药剂的施药量、持效期、防效和药后存活虫量,建议以30%氯虫·噻虫嗪SC和14%氯虫·高氯氟CS作为全程以UAV为施药机械防治稻水象甲的首选药剂,在稻水象甲种群发展前中期优先考虑低浓度施药量;同时,为避免UAV在实际作业中药液雾滴发生飘失和流失问题,可以考虑添加飞防助剂提升防效。     

圈养白头叶猴春季昼夜活动节律

2008 年3 ～5 月,采用瞬时扫描法,对上海动物园5 只白头叶猴的行为进行24 h 昼夜连续观察。结果表明:春季圈养白头叶猴一天的活动起于06∶ 00 左右,结束于18∶ 00 或18∶ 30。白天白头叶猴的主要行为为休息、取食和移动,平均频次依次是13.79 次、4.75 次和2.18 次。夜间的主要行为为休息、移动和抓挠,平均频次依次是22.13 次、0.43 次和0.26 次。不同个体昼夜活动节律差异很大。其中,移动、理毛、玩耍和其它行为的差异显著。夜间无理毛和玩耍行为,移动行为在夜间21∶ 00, 00 ∶ 30, 03∶00 和04∶ 30 出现高峰。在22∶ 30, 01∶ 00, 02∶ 00, 03∶ 30, 04∶ 30 和05∶30 则出现抓挠高峰。这预示白头叶猴夜间休息时处于一个“轻睡眠”状态。同时,雌雄白头叶猴昼夜移动行为差异显著。     

艾灸干预不同穴位对束缚应激模型大鼠心理行为改变的影响

目的:观察艾灸不同穴位对束缚应激模型大鼠行为学改变的影响,进一步探讨艾灸对束缚应激所致心理行为改变的作用规律。方法:将35只雄性Wistar大鼠按分层随机法分为正常组、束缚应激模型组、艾灸百会(GV20)组、艾灸关元(CV4)组、艾灸足三里(ST36)组,每组各7只。除正常组外,余各组均采用自制布袋束缚大鼠30 min,每日1次,共20次,制备束缚应激大鼠模型,于造模第2天各治疗组捆绑固定后给予艾炷灸3壮,正常组及模型组捆绑束缚20 min,隔日一次,共10次。于造模前、造模后,治疗5次、10次分别采用高架十字迷宫检测各组大鼠开放臂进入次数比例(OE%)及开放臂停留时间比例(OT%)的变化。结果:①与造模前比较,艾灸百会(GV20)组大鼠造模后、治疗10次后OE%均降低明显,治疗5次后OT%升高明显,均有显著性差异(P<0.05),艾灸关元(CV4)组大鼠造模后OT%降低明显,有显著性差异(P<0.05),艾灸足三里(ST36)组大鼠造模后OE%和OT%、治疗10次后OE%均明显降低,均有显著性差异(分别为P<0.05,P<0.05,P<0.01);与造模刚结束比较,艾灸百会(GV20)组大鼠治疗5次后OE%与OT%均升高明显,均有显著性差异(P<0.05),艾灸关元(CV4)组大鼠治疗10次后OT%升高明显,有显著性差异(P<0.01),艾灸足三里(ST36)组大鼠治疗5次后OE%、治疗10次后OT%均明显升高,有显著性差异(分别为P<0.01,P<0.05);与治疗5次比较,艾灸百会(GV20)组、足三里(ST36)组大鼠治疗10次后OE%明显降低,艾灸关元(CV4)组大鼠治疗10次后OE%和OT%升高明显,均有显著性差异(P<0.05)。②与艾灸百会(GV20)组比较,艾灸关元(CV4)组与艾灸足三里(ST36)组大鼠在治疗5次、10次后OE%和OT%呈不同程度的升高或降低趋势,未见显著性差异(P>0.05)。结论:艾灸不同穴位可一定程度改善慢性束缚应激所致大鼠焦虑心理行为的变化;关元(CV4)、百会(GV20)、足三里(ST36)三穴均表现出一定抗焦虑效应,百会(GV20)穴在治疗早期效果显著,足三里(ST36)穴的疗效肯定,而关元(CV4)穴在长期治疗中效应更为稳定、明显,具有相对特异性。     

Effect of ACTH (tetracosactide) on steroid hormone levels in the mare. Part A: effect in intact normal mares and mares with possible estrous related behavioral abnormalities

Ovariectomized mares and mares with inactive ovaries may show signs of estrus. The reason behind this phenomenon is not clear; however, steroid hormones of adrenal origin have been suggested. Moreover, aberrant adrenal hormone production has been implied as a reason why some intact mares may change behavior. In the present study, the effect of ACTH on plasma levels of cortisol, progesterone, androstenedione and testosterone was investigated in intact mares with normal estrous behavior ('controls', n=5) and intact mares that according to their owners showed deviant estrous behavior ('problem' mares, n=7). Blood samples were collected hourly from 12:00 h until 14:00 h the following day (half-hourly between 14:00 and 17:00 h) on two occasions (at two estruses), with saline or ACTH treatment (tetracosactide) at 14:00 h (saline treatment day or ACTH treatment day). ACTH treatment caused a significant increase in plasma levels of cortisol, progesterone, androstenedione and testosterone in all mares (P<0.05). An overall significant difference in cortisol response to ACTH was found (P<0.05), with 'problem' mares showing a significantly lower increase in cortisol levels 30 min to 3h post ACTH treatment (P<0.001). The 'problem' mares also showed a significantly higher increase than controls in progesterone levels in the same time period (P<0.05). The reason for the reduced adreno-cortical reactivity, with a low cortisol response to the ACTH treatment, in the 'problem' mares is unknown, but may indicate a difference in adrenal function as compared to control mares.     

Food intake and body positional change alter the circadian rhythm of atrial natriuretic peptides excretion into human urine.

The 98 amino acid (a.a.) N-terminus of the 126 a.a. atrial natriuretic factor prohormone contains two natriuretic and vasodilatory peptides consisting of a.a. 1-30 (proANF 1-30) and a.a. 31-67 (proANF 31-67). The N-terminus and C-terminus (a.a. 99-126, i.e., ANF--also a vasodilatory peptide) circulate normally in humans with a circadian peak at 04:00 h in plasma. To determine if the N-terminus and C-terminus of the ANF prohormone are present in urine and possibly have a circadian variation in urine, six healthy volunteers had urine samples hourly while awake and every 3 h during sleep for five consecutive days obtained for radioimmunoassay. The sleep-awake pattern was varied so that after 2 days of normal sleep (supine)-awake (upright) positions, these volunteers were supine from 15:00 h on the third day until 10:00 h of the fourth day. They were then upright until 19:00 h that day when they became supine again until 02:30 h, and then were upright until 10:00 h of day 5. Three radioimmunoassays that immunologically recognize (a) the whole N-terminus (i.e., amino acids 1-98), (b) the midportion of the N-terminus (amino acids 31-67), and (c) the C-terminus of the ANF prohormone were utilized. ProANF 1-98, proANF 31-67, and the ANF radioimmunoassays each detected their respective peptides in urine. A circadian peak for each of these peptides was detected at 04:00 to 05:00 h whether the person was supine or upright during the night, which were significantly (p less than 0.001) higher than their concentrations in the afternoon of the previous days. Assuming a supine position during the day caused a significant (p less than 0.01) two- to threefold increase in these peptides in the urine. Food intake also increased the concentrations of proANF 1-98, proANF 31-67, and ANF in urine (p less than 0.001). Fluid intake when abstaining from food throughout the day lowered the concentration of these peptides in the urine. It was concluded that there is a circadian rhythm in both the N-terminus and C-terminus of the ANF prohormone excretion into urine with a peak at 04:00 h irrespective of posture, but that both posture and food and fluid intake throughout the day significantly influence the excretion of these peptides into the urine, with supine posture and food increasing their concentrations in the urine while fluid intake decreases their concentrations in the urine.     

Lethal and sublethal effects of rice polishing process on Sitophilus oryzae (Coleoptera: Curculionidae)

The mechanical impact of rice polishingon the rice weevil, Sitophilus oryzae (L.), and the subsequent postpolishing effects associated with rice quality were studied. "Brown" rice (not polished), "White (infest then polish)" rice, and "White (polish then infest)" rice were used with different polishing process intensities and different initial weevil densities. Weevil progeny were more numerous in Brown than in White (infest then polish) or White (polish then infest) rice. Polishing corresponding to a weight loss of 11% in rice generated an immediate mortality of approximately 40%; the subsequent mortality caused by rice quality was also 40% (total >80%). A polishing process corresponding to 14 and 16% of rice weight loss generated a drastic mortality in the weevil population (>95%). The progeny per adult weevil was similar with high and low initial weevil densities. The development of weevil progeny was also delayed by about 1 wk in White (infest then polish) rice compared with Brown rice. Furthermore, weevil adults of the progeny were significantly heavier in Brown than in White (infest then polish) or White (polish then infest) rice.