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Multiple Regression and Path Analysis of Morphological,Weight,and Fecundity Traits of Diploid and Tetraploid Pacific Oyster,Crassostrea gigas
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作者 CHENG Geng HU Hong +4 位作者 LIANG Yuanxin BI Wenlong XU Chengxun LIU Haijun LI Qi 《Journal of Ocean University of China》 2026年第1期263-272,共10页
Triploid Pacific oysters(Crassostrea gigas)are highly valued due to their rapid growth and low fertility,making them commercially desirable.However,these reproductive characteristics also hinder their capability to pr... Triploid Pacific oysters(Crassostrea gigas)are highly valued due to their rapid growth and low fertility,making them commercially desirable.However,these reproductive characteristics also hinder their capability to produce subsequent generations.Large-scale triploid production relies on crossing female diploid and male tetraploid oysters.This study assessed the effects of shell morphology on body weight and fecundity in diploid and tetraploid oysters using multiple regression and path analysis.Substantial correlations were found between shell morphology and body weight traits,as well as between shell morphology and fecundity traits across diploid and tetraploid oysters.Path analysis revealed that shell morphology traits significantly impact body weight and fecundity in both diploids and tetraploids.Among these traits,shell height had the strongest direct effect on body weight and fecundity,while shell height and shell length notably contributed through indirect effects.These findings highlight the importance of shell height in shaping body weight and fecundity in diploid and tetraploid Pacific oysters,indicating that selective breeding,with a particular focus on enhancing shell height,could simultaneously promote increases in shell length. 展开更多
关键词 Crassostrea gigas TETRAPLOID fecundity growth trait
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Early life food intake modulates effects of diet restriction on lifespan and fecundity in later life in a predatory mite(Acari:Phytoseiidae)
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作者 Yun Xu Keshi Zhang +1 位作者 Xiao Han Zhi-Qiang Zhang 《Current Zoology》 2025年第3期295-303,共9页
The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phy... The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phytoseidae),the plasticity of life history traits,such as developmental time and size at maturity,is influenced by the quality and quantity of food.This study aimed to investigate the effects of dietary restriction at different life stages(i.e.,juvenile,early adulthood,and later adulthood)on the lifespan and fecundity of P persimilis.We found that reduced dietary intake during early adulthood resulted in a shorter lifespan for both male and female P persimilis.Furthermore,this study demonstrated a sex-specific response to dietary restriction:it extended the lifespan of males but reduced that of females during later adulthood.Diet restriction during the postovipositional period of females showed the most variable life history trait response.Our results showed that the impact of diet restriction at different life stages can have combined influences on the postovipositional duration of P persimilis,where the individuals receiving diet restriction during immature development and early adulthood had a greater reduction in ovipositional duration as those experiencing diet restriction during late adulthood.In addition,we observed a positive correlation between the lifespan and fecundity of females,with higher prey availability increasing both.The insights obtained from our research contribute to a better understanding of the aging process and dietary requirements of P persimilis,which can facilitate the development of more effective biological control strategies using this predator for spider mites in agriculture. 展开更多
关键词 aging diet restriction fecundity phenotypic plasticity Phytoseiulus persimilis silver-spoon hypothesis.
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Study on Developmental Durations and Fecundity of Phenacoccus solenopsis Tinsley on Four Species of Hosts 被引量:7
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作者 关鑫 陆永跃 曾玲 《Agricultural Science & Technology》 CAS 2012年第2期408-411,共4页
[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Ph... [Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton (Gossypium spp.), tobacco( Nicotiana tabacum), potato (Solanum tuberosum L) and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato. 展开更多
关键词 Phenacoccus solenopsis Tinsley Host plants Development duration fecundity
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瓜实蝇和南亚实蝇的产卵特性比较
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作者 胡英 李貌 +6 位作者 韦晓曼 李娟 杨云芳 张金龙 陈国华 周忠实 张晓明 《生态学杂志》 北大核心 2026年第1期230-236,共7页
瓜实蝇(Bactrocera cucurbitae)和南亚实蝇(B.tau)为近缘种,在田间常混合发生,导致防治困难。为明确二者的产卵规律,本研究通过人工气候箱培养瓜实蝇和南亚实蝇,测定二者的产卵情况和产卵历期等参数,并分析了它们的年龄和产卵量之间的... 瓜实蝇(Bactrocera cucurbitae)和南亚实蝇(B.tau)为近缘种,在田间常混合发生,导致防治困难。为明确二者的产卵规律,本研究通过人工气候箱培养瓜实蝇和南亚实蝇,测定二者的产卵情况和产卵历期等参数,并分析了它们的年龄和产卵量之间的相关性。研究表明,瓜实蝇成虫平均寿命和产卵期分别为78.83和61.47 d,短于南亚实蝇的94.77和75.33 d;南亚实蝇单雌日均产卵量和平均窝卵数为10.64粒和8.83个,均高于瓜实蝇的6.57粒和6.56个;南亚实蝇盛卵期比瓜实蝇长4 d,且其平均累计产卵625.87粒,比瓜实蝇的431.41粒多200粒左右。可见,南亚实蝇具有更高的产卵竞争优势。在田间防治时,需在实蝇产卵之前采取有效防治措施,并针对不同暴发对象制定相应防控措施,以发生危害较重的实蝇为主要防治对象,兼治另一种实蝇。 展开更多
关键词 瓜实蝇 南亚实蝇 产卵期 产卵量 种间竞争
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鸡皮刺螨生殖特性研究进展
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作者 刘勃兴 郭旭东 +2 位作者 孙玮玮 张迪 潘保良 《中国家禽》 北大核心 2026年第2期112-119,共8页
鸡皮刺螨(Dermanyssus gallinae),作为全球养鸡业重要的吸血性外寄生虫,以禽类血液为食的生物学特性不仅导致鸡不安、贫血、生产性能下降,还作为传播病原生物的媒介,给养殖场造成重大经济损失。作为一种繁殖能力很强的节肢动物,鸡皮刺... 鸡皮刺螨(Dermanyssus gallinae),作为全球养鸡业重要的吸血性外寄生虫,以禽类血液为食的生物学特性不仅导致鸡不安、贫血、生产性能下降,还作为传播病原生物的媒介,给养殖场造成重大经济损失。作为一种繁殖能力很强的节肢动物,鸡皮刺螨的种群扩散与其生殖特性密切相关,如雌螨单次受精终身产卵、高效的繁殖力,但当前关于其生殖特性的了解有限。文章通过对鸡皮刺螨的繁殖方式、性别二态性、生殖系统、交配行为、生殖力和生殖相关基因等进行综述,为研发新型防控手段提供理论基础,对降低化学杀虫试剂依赖、实现生态友好型防控具有重要意义,从而促进养鸡业的健康发展。 展开更多
关键词 鸡皮刺螨 生殖特性 生殖力 防控
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不同高粱品种对草地贪夜蛾生长发育和繁殖的影响
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作者 金银利 马全朝 +3 位作者 陶玉红 黄建荣 李国平 封洪强 《植物保护》 北大核心 2026年第2期290-296,303,共8页
草地贪夜蛾Spodoptera frugiperda是一种迁飞性重大农业害虫,主要嗜食玉米,近年来还在高粱田发生为害。为了明确不同高粱品种对草地贪夜蛾生长发育和繁殖的影响,本文系统比较了取食3种高粱叶片的草地贪夜蛾的发育历期、存活率、产卵量... 草地贪夜蛾Spodoptera frugiperda是一种迁飞性重大农业害虫,主要嗜食玉米,近年来还在高粱田发生为害。为了明确不同高粱品种对草地贪夜蛾生长发育和繁殖的影响,本文系统比较了取食3种高粱叶片的草地贪夜蛾的发育历期、存活率、产卵量和生命表参数。结果表明,取食甜高粱和红高粱的草地贪夜蛾幼虫总历期分别为(14.80±0.27)d和(15.12±0.24)d,显著低于取食白高粱的幼虫总历期(16.03±0.39)d。取食甜高粱和红高粱品种叶片的草地贪夜蛾幼虫存活率均为98.00%,显著高于取食白高粱品种叶片的草地贪夜蛾幼虫存活率(60.00%)。取食甜高粱品种叶片的草地贪夜蛾单雌产卵量[(697.20±86.30)粒],与取食白高粱品种叶片的[(603.85±110.22)粒]无显著差异,但显著高于取食红高粱品种叶片的[(379.29±57.32)粒]。从寄主适合度指数来看,取食甜高粱的为10.20,大于取食红高粱(7.45)和白高粱(6.59)的。取食甜高粱、红高粱和白高粱叶片的草地贪夜蛾净增殖率(R_(0))分别为306.37、175.21和125.66,内禀增长率(r_(m))分别为0.20、0.18和0.15。研究发现,草地贪夜蛾在不同高粱品种叶片上均可以完成生活史,但寄主适合度因高粱品种的不同而有所差异,其更倾向于取食甜高粱品种叶片,且其种群增长增殖能力最强。研究结果可为我国不同品种高粱的安全生产和草地贪夜蛾的发生规律及监测预警提供科学参考依据。 展开更多
关键词 草地贪夜蛾 高粱品种 发育历期 存活率 繁殖力 生命表参数
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成虫期饲养密度、性比及补充营养对孟氏隐唇瓢虫生殖力的影响
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作者 杨希陶 张月青 +5 位作者 符悦冠 朱俊洪 叶政培 郑丽旧 陈俊谕 张方平 《植物保护》 北大核心 2026年第1期128-134,177,共8页
为明确成虫期的饲养密度、性比及补充营养对孟氏隐唇瓢虫Cryptolaemus montrouzieri Mulsant生殖力的影响,在温度(27±1)°C、光周期L//D=8 h//16 h,以柑橘臀纹粉蚧Planococcus citri(Risso)为猎物观察了不同瓢虫密度(1♂+2♀、... 为明确成虫期的饲养密度、性比及补充营养对孟氏隐唇瓢虫Cryptolaemus montrouzieri Mulsant生殖力的影响,在温度(27±1)°C、光周期L//D=8 h//16 h,以柑橘臀纹粉蚧Planococcus citri(Risso)为猎物观察了不同瓢虫密度(1♂+2♀、2♂+4♀、3♂+6♀、4♂+8♀、5♂+10♀/1000 mL)、性比(♂∶♀=1∶1、1∶2、1∶3、1∶4、1∶5)、补充营养物质(柑橘臀纹粉蚧、丰年虾卵、蔗糖水、清水)的产卵情况。结果表明,随着成虫密度的增加,孟氏隐唇瓢虫单雌产卵量呈下降趋势,当成虫密度为(1♂+2♀)/1000 mL时,单雌产卵量最高为514.5粒,密度为(5♂+10♀)/1000 mL时,单雌产卵量最低,为331.3粒;性比(♂∶♀)为1∶1时的单雌产卵量最高,性比为1∶5时的单雌产卵量最低;成虫期替代食物为柑橘臀纹粉蚧时产卵量最高,其次为20%蔗糖水。综上,在成虫密度较低、雌雄性比1∶1条件下,孟氏隐唇瓢虫雌虫的生殖力更强,成虫期在食物不足的情况下,可用20%蔗糖水作为暂时补充,这些结果为孟氏隐唇瓢虫的商品化生产及田间应用提供了理论依据及指导。 展开更多
关键词 孟氏隐唇瓢虫 生殖力 饲养密度 性比 补充营养
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Fecundity of Hemirhamphus sajori (T. et S.)in the Yellow and Bohai Seas 被引量:1
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作者 刘群 任一平 尤凯 《青岛海洋大学学报(自然科学版)》 CSCD 1999年第2期229-233,共5页
1993年5月在荣成和龙口,1994年5月在青岛和庄河收集了小鳞鱼箴(Hemirhamphussajori,T.etS.)标本。分析结果表示1994年繁殖力(平均22974)大于1993年繁殖力(平均16040)。卵... 1993年5月在荣成和龙口,1994年5月在青岛和庄河收集了小鳞鱼箴(Hemirhamphussajori,T.etS.)标本。分析结果表示1994年繁殖力(平均22974)大于1993年繁殖力(平均16040)。卵径分布和平均体长指示洄游距离较长的个体的卵径和体长较大。 展开更多
关键词 小鳞Zhen 繁殖力 黄海 渤海 卵径分布
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瓜实蝇黏连蛋白复合体亚基基因Zcsolo和Zcsunn的克隆、表达谱和功能分析
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作者 金倩倩 马卢杰 +1 位作者 林先武 颜日辉 《昆虫学报》 北大核心 2026年第2期168-177,共10页
【目的】鉴定并探究黏连蛋白复合体(cohesin complex)亚基ZcSOLO和ZcSUNN在瓜实蝇Zeugodacus cucurbitae两性生殖中的功能,为深入揭示黏连蛋白复合体在瓜实蝇减数分裂和生殖调控中的功能奠定基础。【方法】通过比对NCBI数据库获得瓜实蝇... 【目的】鉴定并探究黏连蛋白复合体(cohesin complex)亚基ZcSOLO和ZcSUNN在瓜实蝇Zeugodacus cucurbitae两性生殖中的功能,为深入揭示黏连蛋白复合体在瓜实蝇减数分裂和生殖调控中的功能奠定基础。【方法】通过比对NCBI数据库获得瓜实蝇ZcSOLO和ZcSUNN的氨基酸和核苷酸序列,以性成熟瓜实蝇卵巢提取的RNA合成的cDNA为模板克隆Zcsolo和Zcsunn的编码序列(coding sequence,CDS)并测序和生物信息学分析。利用qPCR检测Zcsolo和Zcsunn在瓜实蝇不同发育阶段[胚胎(产卵后15 s及1,2,3,6,12,18和24 h)、幼虫(1,3和7日龄)、蛹(1,5和9日龄)和成虫(1,5,7,10和15日龄)]以及10日龄成虫组织(头、胸、腹、足、精巢和卵巢)中的表达量。通过注射dsRNA利用RNAi介导敲降瓜实蝇3日龄成虫Zcsolo和Zcsunn,在显微镜下观察雌成虫卵巢发育,测量卵巢面积、生殖腺形态大小以及交配后的10 d产卵量和卵孵化率。【结果】克隆得到瓜实蝇Zcsolo和Zcsunn正确的CDS。Zcsolo的CDS由5个外显子组成,长度为2493 bp,Zcsunn的CDS由15个外显子组成,长度为2736 bp;瓜实蝇和黑腹果蝇Drosophila melanogaster SOLO和SUNN的蛋白的三维结构非常相似且同源性较高。Zcsolo和Zcsunn在成虫生殖腺中特异性高表达,暗示这两个基因可能与成虫生殖力有关。RNAi介导的Zcsolo和Zcsunn下调导致卵巢发育迟缓、成熟卵泡减少;Zcsolo和Zcsunn RNAi后的雌成虫与野生型雄成虫交配后雌成虫10 d产卵量以及卵孵化率显著降低;Zcsolo和Zcsunn RNAi后的雄成虫与野生型雌成虫交配后野生型雌成虫10 d产卵量未受显著影响但受精后的卵孵化率显著下降,说明Zcsolo和Zcsunn RNAi后雄成虫生殖力减弱。【结论】本研究证实了Zcsolo和Zcsunn对瓜实蝇两性生殖力的必需性,为基于生殖干扰的害虫防控策略提供理论基础。 展开更多
关键词 瓜实蝇 黏连蛋白 Zcsolo Zcsunn 生殖力 RNA干扰
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三种寄主植物上烟蓟马生长发育和繁殖力的比较
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作者 常译方 孙浩宇 +2 位作者 李文宇 孙丽娟 郑长英 《昆虫学报》 北大核心 2026年第2期223-231,共9页
【目的】烟蓟马Thrips tabaci作为葱蒜作物上的重要害虫,在我国各省(自治区、直辖市)均有为害,其寄主范围涵盖大葱Allium fistulosum、蒜、番茄、马铃薯、瓜类、豆类、十字花科蔬菜以及烟草、棉花等数十种作物,但针对其在不同寄主植物... 【目的】烟蓟马Thrips tabaci作为葱蒜作物上的重要害虫,在我国各省(自治区、直辖市)均有为害,其寄主范围涵盖大葱Allium fistulosum、蒜、番茄、马铃薯、瓜类、豆类、十字花科蔬菜以及烟草、棉花等数十种作物,但针对其在不同寄主植物上的生物学特性研究较少。本研究通过构建烟蓟马在3种寄主植物上的年龄-龄期两性生命表,研究烟蓟马在3种寄主植物(大葱叶片、韭菜A.tuberosum叶片和芸豆Phaseolus vulgaris豆荚)上的生长发育繁殖特性,从而掌握其生物学特性,为室内种群饲养和科学防治提供依据。【方法】在温度(25±0.5)℃、相对湿度55%±5%和光周期16L∶8D的实验室控制条件下,构建其年龄-龄期两性生命表,研究大葱叶片、韭菜叶片和芸豆豆荚对烟蓟马种群的影响,使用TWOSEX-MSChart程序计算发育历期、总产卵前期、单雌产卵量、寿命期望值、繁殖值等参数,并利用TIMING-MSChart程序预测了种群发展趋势。【结果】以芸豆豆荚为食的烟蓟马未成熟期(14.71 d)、成虫寿命(15.80 d)、平均世代周期T(26.34 d)显著长于取食大葱叶片的烟蓟马(分别为13.93,11.11和23.45 d)及取食韭菜叶片的烟蓟马(分别为13.90,10.80和23.01 d),取食芸豆豆荚的烟蓟马的净增殖率R_(0)(11.08)、内禀增长率r(0.0913 d^(-1))和周限增长率λ(1.09 d^(-1))显著高于取食大葱叶片的烟蓟马(分别为4.32,0.0624 d^(-1)和1.06 d^(-1))及取食韭菜叶片的烟蓟马(分别为4.28,0.0632 d^(-1)和1.06 d^(-1)),而取食大葱叶片的烟蓟马与取食韭菜叶片的烟蓟马两者之间的净增殖率、内禀增长率和周限增长率无显著差异。【结论】室内饲养烟蓟马,在大葱叶片、韭菜叶片和芸豆豆荚上均可完成其生活史,其中取食芸豆豆荚的烟蓟马相较于取食其他两种寄主植物的烟蓟马虽然未成熟期更长,但繁殖力最高,种群繁殖能力最强,芸豆更有利于烟蓟马的种群增长。本研究为烟蓟马种群预测与田间防控提供了理论依据。 展开更多
关键词 烟蓟马 寄主植物 生长发育 繁殖力 两性生命表
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Normal reference ranges for semen quality and their relations to fecundity 被引量:15
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作者 Niels E. Skakkebaek 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第1期95-98,共4页
Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization ... Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization guidelines for semen analysis recommend lowering the lower cutoff value for normal sperm concentration from 20 to 15 million spermatozoa per mL. As a result large groups of subfertile men across the world may not receive appropriate andrological help in the future. 展开更多
关键词 semen quality INFERTILITY sperm morphology fecundity
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LABORATORY OBSERVATION ON SPAWNING,FECUNDITY AND LARVAL DEVELOPMENT OF AMPHIOXUS (BRANCHIOSTOMA BELCHERI TSINGTAUNESE) 被引量:8
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作者 吴贤汉 张士璀 +3 位作者 王永元 张宝禄 曲艳梅 江新霁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第4期289-294,共6页
Although amphioxus is widespread in temperate and tropical seas,its population is diminishing be-cause of environmental pollution.To keep the population of this evolutionarily important animal fromdiminishing,study on... Although amphioxus is widespread in temperate and tropical seas,its population is diminishing be-cause of environmental pollution.To keep the population of this evolutionarily important animal fromdiminishing,study on its reproduction and development is necessary.The main findings in this study onthe spawning and fecundity of the amphioxus reared in laboratory and its larval development are as fol-lows.1.Water temperature markedly affected the spawning.It spawned only when water temperature reached 21℃.2.Spawning of the amphioxus in laboratory was markedly extended.Initially,the amphioxus spawned at about 7:00 PM,but spawning time was postponed as spawning days went on.3.The number of eggs produced by a female ranged from 1400 to 12800,average of 5800.This al-so represents the fecundity of the amphioxus because it shedded all eggs within the ovary at a time.4.During the first few months of life of the amphioxus,its growth rate changed seasonally.Thegrowth rate in summer and fall was greater than that 展开更多
关键词 AMPHIOXUS SPAWNING fecundity LARVAL development
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Tail loss affects fecundity but not offspring traits in the Chinese skink Eumeces chinensis 被引量:6
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作者 Hongliang LU Jianfang GAO +2 位作者 Xiaohao MA Zhihua LIN Xiang JI 《Current Zoology》 SCIE CAS CSCD 2012年第2期228-235,共8页
We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive in- vestment and offspring traits. A total of 147 wild-captured adult females were divided into four grou... We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive in- vestment and offspring traits. A total of 147 wild-captured adult females were divided into four groups according to their tail con- ditions. Tail breaks occurred most frequently in the proximal portion of the tail and least frequently in the distal portion, with the middle portion in between. This finding suggests that tail breaks occurring in nature often entails substantial energetic costs in E. chinensis where the tail is a major site of energy storage. The proportion of females that laid eggs was higher in females with in- tact or completely regenerated tails than in those with broken tails. Following whole-tail autotomy, the clutch size was reduced by 17%, and the clutch mass was reduced by 14%. Females undergoing substantial tail autotomy reduced reproductive investment, and they did so by reducing the number but not the size of eggs produced. None of the egg and hatchling traits was affected by tail loss. Comparing our data with those reported for other oviparous and viviparous skinks allows us to draw two general conclu- sions: one is that fecundity (clutch or litter size) is affected by tail loss in all species so far studied, whereas offspring size is af- fected by tail loss in some species, but not in others; the other is that the reduction in fecundity following tail loss is more evident in species lacking abdominal fat bodies 展开更多
关键词 Scincid lizard Costs of tail autotomy fecundity Offspring size Morphology Locomotor performance
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Screening of Brown Planthopper Resistant miRNAs in Rice and Their Roles in Regulation of Brown Planthopper Fecundity 被引量:3
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作者 LÜJun LIU Jinhui +5 位作者 CHEN Lin SUN Jiawei SU Qin LI Shihui YANG Jianhua ZHANG Wenqing 《Rice science》 SCIE CSCD 2022年第6期559-568,I0031-I0033,共13页
MicroRNAs(miRNAs)can participate in plant-insect interactions,which regulate plant defense networks.In this study,we analyzed the miRNA expression profiles of six rice varieties before and after brown planthopper(BPH)... MicroRNAs(miRNAs)can participate in plant-insect interactions,which regulate plant defense networks.In this study,we analyzed the miRNA expression profiles of six rice varieties before and after brown planthopper(BPH)-feeding.We identified 45 differentially expressed miRNAs between BPH-susceptible and BPH-resistant rice varieties and 144 miRNAs that responded to BPH-feeding.Thus,miRNAs may be involved in multiple pathways regulating rice defense response against BPH.In addition,we found that the genetic history of rice varieties determined the regulation mode of the miRNA and affected the amounts,types,changing trends and response periods of miRNAs in response to BPH-feeding.To conclude,we scanned seven potential cross-kingdom miRNAs,of which miR5795 may target the vitellogenin gene in BPH,causing a 16.07%reduction in BPH oviposition.The results provide new miRNA information of rice-BPH interactions and BPH-resistant rice variety breeding. 展开更多
关键词 Nilaparvata lugens insect-resistant rice miR5795 fecundity
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Early social conditions affect female fecundity in hermaphrodites 被引量:2
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作者 Elio CANNARSA Mafia Cristina LORENZI Gabriella SELLA 《Current Zoology》 SCIE CAS CSCD 2015年第6期983-990,共8页
Social conditions experienced prior to sexual maturity influence reproduction later in life in many animals. In simulta- neous hermaphrodites, variation in mating group size influences reproductive investment. As the ... Social conditions experienced prior to sexual maturity influence reproduction later in life in many animals. In simulta- neous hermaphrodites, variation in mating group size influences reproductive investment. As the mating group size increases, re- productive resources devoted to the female function decrease in favor of the male function. Prior to sexual maturity, many her- maphrodites have a protandrous phase during which they produce sperm and can fertilize hermaphrodites' eggs. In the simulta- neously hermaphroditic polychaete worm Ophryotrocha diadema, the cost of male reproduction during adolescence is spread over the whole energy budget of worms as shown by a reduced growth rate, a delayed age at sexual maturity and the shortening of life span compared to protandrous males that do not reproduce. Little is known on whether social conditions experienced dur- ing development affect reproductive investment of immature individuals. We investigated whether social conditions affected the length of the protandrous phase, body size and also the subsequent female fecundity of same-age protandrous individuals of O. diadema, which did not had to face competition for egg fertilization. Results show that in large group sizes protandrous males lengthened their protandrous phase, slowed down body growth and decreased their individual investment at the first egg laying compared to protandrous males that were reared in isolation. In the successive egg layings worms adjusted their egg output to the current social conditions. We interpreted these results as an indication that early social conditions represent a social stress result- ing in a reduction of the overall reproductive resources up to the first egg laying . 展开更多
关键词 Social stress Early experience Ophryotrocha diadema Female fecundity Social environment
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Effects of ethanol extract of leaves of Helianthus annus on the fecundity of Wistar rats 被引量:1
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作者 Ejebe Daniel Emamuzo Siminialayi Iyeopu Miniakiri +2 位作者 Emudainohwo Joseph Oghenebrorie Tedwin Kagbo Hope Delesi Amadi Precious 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第6期435-438,共4页
Objective:To evaluate the effects of ethanol extract of leaves of Helianthus annus(H.annus) on the fecundity of Wistar rats.Methods:Forty(20 male and 20 female) Wistar rats,grouped into control,ethanol extract treated... Objective:To evaluate the effects of ethanol extract of leaves of Helianthus annus(H.annus) on the fecundity of Wistar rats.Methods:Forty(20 male and 20 female) Wistar rats,grouped into control,ethanol extract treated rats and untreated,were used for the study.Treated rats had 0.5 g/kg of ethanol extract orally for 2 weeks;control rats had 5%alcoholic water(solvent);and untreated rats had their normal feed and clean drinking water.Following treatment,the animals were sub-grouped into 5 mating groups to observe the coital frequency,pregnancy rate and average number of pups per group in pairs.Results:The results showed that coital frequency was unaffected by the extract treatment but pregnancy rate and number of pups per rat and per group were reduced significantly in groupsⅡ,ⅢandⅣcompared to those of groupⅠandⅤrats which were not treated with the ethanol extract of leaves of H.annus.Conclusions:The histodegenerative in the gonads reportedly induced by this ethanol extract in previous studies may be responsible for the reduced fecundity observed in treated adult rats. 展开更多
关键词 ETHANOL EXTRACT HELIANTHUS annus LEAVES fecundity RATS
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Fecundity and egg hatchability of Dastarcus helophoroides adults fed on different types of artificial diets 被引量:3
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作者 Xiao-juan Li Guang-ping Dong +1 位作者 Li Yang Wan-lin Guo 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期219-224,共6页
Both fecundities and egg hatchabilities were compared among three populations of Dastarcus helophoroides Fairmaire adults(Coleoptera: Bothrideridae) fed on three types of artificial diets(Diet of formula 1 compose... Both fecundities and egg hatchabilities were compared among three populations of Dastarcus helophoroides Fairmaire adults(Coleoptera: Bothrideridae) fed on three types of artificial diets(Diet of formula 1 composed of silkworm pupa powder, dried yeast powder,sucrose, peptone, egg yolk powder and poplar branch powder. Diet of formula 2 composed of silkworm pupa powder, dried yeast powder, sucrose, egg yolk powder,poplar branch powder, cricket powder, benzoic acid and distilled water. Diet of formula 3 composed of pine bark powder and Monochamus alternatus larva powder). for90 days. The three diets showed no significant difference regarding the average number of eggs deposited by all D. helophoroides females(16622.3–23874.7); the average number of eggs per female(1278.6–1836.5); and the average number of eggs per female per day(14.2–20.4).The number of eggs one cluster contained mainly(82.06–82.66 %) lied in 1–100 eggs, and the average number of eggs per cluster ranged from 61.7 to 63.1. In the first 10-day period, the number of eggs deposited by all females fed on formula 1 was significantly larger than that on formula 3. The eggs deposited in the last four 10-day periods were more than in the former five 10-day periods,on formula 3. There were no significant differences in hatchability of total eggs among the three artificial diets,and the average corrected egg hatchability ranged from82.85 to 84.78 %. No significant differences in the adult mortality and mean weight gain of D. helophoroides were found after feeding on three artificial diets. Our results suggest that D. helophoroides adults were not specialized on the diet, and the diet types might have little effect on fecundity and egg hatchability in D. helophoroides, as long as sufficient nutrition was supplied. 展开更多
关键词 Dastarcus helophoroides fecundity Egg hatchability Artificial diet
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Semen Analysis and Fecundity Association Among Women with Polycystic Ovary Syndrome Experiencing Ovulatory Dysfunction Treated by Ovulation Induction 被引量:1
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作者 Jingshu Gao Yu Wang +7 位作者 Mubai Li Mengyi Zhu Xuekui Liu Hongli Ma Yijuan Cao Lu Li Xinming Yang Xiaoke Wu 《Engineering》 SCIE EI 2021年第11期1586-1591,共6页
In this study,normal values of semen analysis were set for a general infertile population of couples among which most women had normal ovulation.The predictive capacity values of sperm quality,including concentration,... In this study,normal values of semen analysis were set for a general infertile population of couples among which most women had normal ovulation.The predictive capacity values of sperm quality,including concentration,motile count,progressive motile count,and morphology,are unclear for women with polycystic ovary syndrome(PCOS).A secondary analysis was conducted based on a randomized controlled trial investigating infertility among women with PCOS experiencing ovulatory disorder between 2011 and 2016 in China.A total of 1000 women received ovulation induction(acupuncture and clomiphene).We randomized the women with PCOS in 27 hospitals in China who received one of four interventions(acupuncture plus clomiphene,sham acupuncture plus clomiphene,acupuncture plus placebo,or sham acupuncture plus placebo).Semen analysis was performed for every male partner according to the World Health Organization(WHO)criteria.The outcomes included conception,clinical pregnancy,and live birth.Logistic regression was used to evaluate the predictive value of semen analysis among ovulatory women for conception,clinical pregnancy,and live birth.Among the 1000 couples,the number of couples who attained ovulation,conception,clinical pregnancy,and live birth were 780,320,235,and 205,respectively.Semen volume and motility were applied and used as prediction parameters for conception(area under the curve(AUC)of 0.62(95%confidence interval(CI),0.55–0.69)),clinical pregnancy(AUC of 0.67(95%CI:0.61–0.73)),and live birth(AUC of 0.57(95%CI:0.50–0.64)).No poor calibration was shown for these models in Hosmer–Lemeshow tests.The predictive capacity of semen analysis for treatment outcome in PCOS women with PCOS experiencing with ovulatory dysfunction is limited. 展开更多
关键词 Semen analysis fecundity Ovulatory dysfunction Predictive capacity
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Effects of Exogenous Hormone on Fecundity of Sliv-er Fox
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作者 Liu Hao 《Animal Husbandry and Feed Science》 CAS 2016年第1期60-62,共3页
The paper aimed to study the effects of exogenous hormone on fecundity of silver fox. Vixens were timely injected with appropriate exogenous hormones at proper ratio to increase their ovulation and litter size, thereb... The paper aimed to study the effects of exogenous hormone on fecundity of silver fox. Vixens were timely injected with appropriate exogenous hormones at proper ratio to increase their ovulation and litter size, thereby improving the fecundity of silver fox. The average litter size in experimental group attained by 5.86 to 6.0 whelps, 1.61 - 1.75 whelps more than that in the control group. The hormone combination in the experimental group was high in performance/price ratio, which had no significant impact on fecundity of vixens in future. 展开更多
关键词 Exogenous hormone Sliver fox fecundity
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Differential Aphid Colony Establishment in <i>Dolichos lablab</i>Varieties Correlated with Some Plant Specific Factors That Impact on Aphid Fecundity
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作者 Hossain Ali Mondal Suvendu Kumar Roy +3 位作者 Lakshmi Hijam Moumita Chakraborty Puspendu Dutta Tapan Kumar Hath 《American Journal of Plant Sciences》 2017年第4期754-769,共16页
Aphid establishes colony in the selective plant parts like vine, leaf petiole, leaflet, inflorescence, and tender fruit in Dolichos lablab Linn but not the entire plant. In this study, the aphid colony establishment i... Aphid establishes colony in the selective plant parts like vine, leaf petiole, leaflet, inflorescence, and tender fruit in Dolichos lablab Linn but not the entire plant. In this study, the aphid colony establishment in vine is focused to understand the differential resistance response between two varieties. At the early stage of aphid infestation, the aphid colony establishment was significantly different between two genotypes (p value = 0.00) and abbreviated as “resistant” variety that supported lower aphid proliferation (mean value = 48.2 ± 2.2) and “susceptible” variety that supported comparatively higher aphid proliferation (mean value = 215.5 ± 16.9). The total aphid number was significantly different between the two varieties, realized at the early infestation stage when both “antixenosis” and “antibiosis” defense mechanisms were working on. Some plant specific factors like vine diameter, wet/ dry weight ratio of vine, phloem sap pressure, the compactness of the vine, wet/dry weight ratio of leaflet, length of leaf petiole, diameter of leaflet vein were identified as modulating factors. The impact of resistant variety on aphid was also investigated for better understanding of aphid defense mechanism. 展开更多
关键词 Dolichos lablab APHID COLONY DIFFERENTIAL VINE Diameter DIFFERENTIAL Wet/Dry Weight Ratio of VINE DIFFERENTIAL Phloem Pressure DIFFERENTIAL Compactness of the VINE DIFFERENTIAL APHID fecundity DIFFERENTIAL Water Content in APHID
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