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1.
大猿叶虫生活史的研究   总被引:30,自引:7,他引:23       下载免费PDF全文
 大猿叶虫Colaphellus bowringi是江西山区十字花科蔬菜上的重要食叶害虫,以成虫在土中越夏和越冬。由于成虫滞育期的差异,该虫的化性显示了明显的种内变异。有些个体隔年繁殖;有些个体是一化性的,仅在春季或秋季繁殖1代;有些个体是二化性的,春季和秋季各繁殖1代;有些个体是多化性的,春季1代,秋季2~3代。因此,大猿叶虫在田间一年可发生4代。在春季,滞育成虫于2月底至4月初陆续出土繁殖;在秋季,滞育成虫于8月中旬至10月初陆续出土繁殖。春季羽化的成虫于4月底至6月上旬陆续入土越夏,秋季羽化的成虫于9月中旬至12月底陆续入土越冬。大猿叶虫一生能交配多次,大多数雌虫的产卵期超过1个月,最长达67天。平均每雌产卵量:春季世代为644粒,秋季世代为963粒,最高达1.950粒。各虫态的发育历期:在15~30℃间,卵为13.78~3.14天,幼虫为22.83~6.95天,蛹为12.10~3.18天。发育阈值温度:卵为10.7℃,幼虫为8.8℃,蛹为9.6℃。非滞育成虫的寿命约为1~2个月,滞育成虫的寿命为5~38个月。滞育成虫均入土蛰伏,在土中的蛰伏深度为9~31 cm 。  相似文献
2.
中国两栖类种群生态研究概述   总被引:15,自引:2,他引:13       下载免费PDF全文
两栖类种群生态学研究从深度和广度上看,均无法与哺乳类和鸟类的相比。然而与哺乳类和鸟类一样,随着生态环境的恶化和生态空间的减少,两栖类各物种种群面临巨大的生存压力,甚至濒临灭绝;因此,广泛深入地开展两栖类种群生态学研究,探讨两栖类与外界环境之间的关系,对环境监测和对两栖类种群的保护与利用均有较大的现实意义和理论意义。为此,重点从两栖类的种群结构与动态规律,摄食行为与食性,怕分析与通讯联系,繁殖过程和繁殖习性,越冬准备和冬眠适应,以及两栖类种群数量下降等方面,对中国研究者的工作进行综述,试图阐述研究现状,存在问题,并分析了尚待加强研究的方面和今后的发展趋势。  相似文献
3.
Body temperature and metabolic rate during natural hypothermia in endotherms   总被引:12,自引:6,他引:6  
During daily torpor and hibernation metabolic rate is reduced to a fraction of the euthermic metabolic rate. This reduction is commonly explained by temperature effects on biochemical reactions, as described by Q 10 effects or Arrhenius plots. This study shows that the degree of metabolic suppression during hypothermia can alternatively be explained by active downregulation of metabolic rate and thermoregulatory control of heat production. Heat regulation is fully adequate to predict changes in metabolic rate, and Q 10 effects are not required to explain the reduction of energy requirements during hibernation and torpor.Abbreviations BMR basal metabolic rate - BW body weight - C thermal conductance - CHL thermal conductance as derived from HL - CHP thermal conductance as derived from HP - HL heat loss - HP heat production - MR metabolic rate - RQ respiratory quotient - Ta ambient temperature - Tb body temperature  相似文献
4.
以改良龙桂开银染法与Fonana-Messon银染法制作冬眠期与非冬眠期中华蟾蜍、黑斑蛙消化管各部组织切片,观察、测量与比较这两种无尾两栖动物冬眠期与非冬眠期消化管嗜银细胞的形态、密度与分布。结果表明:无论冬眠期还是非冬眠期两种动物消化管嗜银细胞的形态、分布规律相似,嗜银细胞的形态与其所在部位及其颗粒分泌方向有关,嗜银细胞在胃幽门处有明显的密度高峰;两种动物消化管嗜银细胞的分布范围、形状在冬眠期与非冬眠期相似,但冬眠期嗜银细胞的密度和嗜银细胞内的嗜银颗粒密度高于非冬眠期,提示这两种动物冬眠期消化管内分泌机能有较大的贮备。  相似文献
5.
李明  梁冰  张树义 《兽类学报》1999,19(1):56-61
用随机扩增DNA多态(RAPD)方法分析白腹管鼻蝠在华北和东北两地冬眠群群内与群间个体之间的亲缘关系,探讨冬眠群的结构组成及其相互关系。结果显示:华北两个白腹管鼻蝠冬眠群内个体间遗传相似性平均分别为0858和0933,两群之间的遗传相似性平均为0842,群内与群间个体之间在遗传相似性方面没有明显差别;东北冬眠群内的遗传相似性平均为0604;华北和东北两地冬眠群间的相似性只有0513和0521。据此可认为,在同一及邻近洞中形成的白腹管鼻蝠冬眠群的组成可能是选择来自同一种群中亲缘关系较近的个体,在华北冬眠的种群和在居留地东北冬眠的种群之间的亲缘关系较远。  相似文献
6.
7.
白腹管鼻蝠两个冬眠群不同个体的随机扩增多态DNA分析   总被引:7,自引:0,他引:7  
李明  张树义 《动物学报》1999,45(2):232-237
用随机扩增多态DNA方法研究了白腹管鼻蝠冬眠群群内与群间个体之间的亲缘关系。结果显示:所研究的两个蝙蝠群内个体的遗传相似性平均为0.86和0.89,两群之间的遗传相似性平均为0.84,群内与群间个体之间在遗传相似性方面有一定差别(P〈0.05)。因此认为:在同一个洞中冬眠的白腹管鼻蝠可能亲缘关系很近,冬眠群的构成在亲缘关系方面存在着一定关系,即亲缘关系有可能影响冬眠群构成。  相似文献
8.
Hibernation in the tropics: lessons from a primate   总被引:7,自引:0,他引:7  
The Malagasy primate Cheirogaleus medius hibernates in tree holes for 7 months, although ambient temperatures during hibernation rise above 30°C in their natural environment. In a field study we show that during hibernation the body temperature of most lemurs fluctuates between about 10°C and 30°C, closely tracking the diurnal fluctuations of ambient temperature passively. These lemurs do not interrupt hibernation by spontaneous arousals, previously thought to be obligatory for all mammalian hibernators. However, some lemurs hibernate in large trees, which provide better thermal insulation. Their body temperature fluctuates only little around 25°C, but they show regular arousals, as known from temperate and arctic hibernators. The results from this study demonstrate that maximum body temperature is a key factor necessitating the occurrence of arousals. Furthermore, we show that hibernation is not necessarily coupled to low body temperature and, therefore, low body temperature should no longer be included in the definition of hibernation.  相似文献
9.
Summary We have analyzed seasonal shifts of energy and time allocation in a population of golden-mantled ground squirrels (Spermophilus saturatus) by directly measuring total daily energy expenditure (DEE) with an isotopic technique (doubly labeled water=dlw), and by estimating components of total DEE through an integration of field behavioral observations with laboratory-measured rates of energy expenditure (oxygen consumption) associated with major behavioral and physiological states. Hibernation laster about 7 1/2 months, and the 4 1/2-month activity season consisted of mating, a 28-d gestation of 3–5 young, 5 1/2 weeks of postnatal growth building to a peak in lactation just before the young emerged above ground, an additional 2–3-week period of maternal care before dispersal, and finally restoration of body mass preceding hibernation. Although the hibernation season comprised nearly two-thirds of the year, it involved only 13–17% of annual energy expenditure, leaving about 85% of energy expenditure for the active season. Ground squirrels were actually present on the surface for only about 11% of the year's time, and the foraging time required to obtain the total annual energy supply amounted to only about 2% of the year's time. The squirrels fed mainly on herbs in the early season and hypogeous fungi later; both were used extensively during peak lactation when female energy expenditure and demand were maximal. Average daily foraging time increased steadily throughout the season to a maximum of 28% of aboveground time as availability of greens diminished and fungus predominated in the diet; time availability did not limit foraging since the animals sat on average for 65% of the daily surface time of about 7 h. Timing of reproduction is apparently optimized such that peak reproductive energy demands are matched with maximal food availability and moderate thermal conditions that minimize energy demand. Despite the greater body mass of males, the greatest total DEE (measured by dlw) of any squirrels at any time of year was that of females during peak lactation. For production of young and lactation through above-ground emergence of an average litter of 2.7, females required a total energy increase of 24% above annual nonreproductive metabolism. Yearling females all bred and performed similarly to older females, yet some costs were greater because the yearlings began and ended hibernation at smaller mass, compensated by giving birth later, and finally showed a greater absolute increase in body mass over the active season than older females. Annual metabolic energy expenditure of breeding males was about 18% greater than that of females, due to greater male body mass. Yet the annual energy intake requirement for both sexes was essentially identical (about 42MJ) due to the greater reproductive export by females in the form of newborn and milk. During the mating season males showed wide-ranging exploratory behavior and social interactions, including aggression, that involved considerable locomotory energy expenditures. Although we did not directly account for the energetics of these specific reproductive behaviors, they are critical to male reproductive success and on a daily basis they probably involved much greater energy expenditure than sperm production. Some yearling males avoided these costs by foregoing testicular development, yet they allocated four times as much energy to growth as older males, thereby increasing somatic condition for the future.  相似文献
10.
冬眠哺乳动物心血管机能特点   总被引:6,自引:0,他引:6  
王世强  周曾铨 《动物学报》1997,43(2):203-208
冬眠动物心血管系统适应于冬眠和激醒过程的特殊生理条件形成了其显著的机能稳定性。我们在总结已有研究的基础提出了冬眠动物心血管系统具有耐低体温,抗主律失常,耐缺氧三大机能特点。这些特点不仅是冬眠动物五非冬眠动物的区别,也是冬眠动物在冬眠季机能强化的方面。  相似文献
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