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31.
相对于标准鼠盒,实验大、小鼠更喜好有筑巢材料的“环境丰荣”鼠盒.向标准鼠盒中放入筑巢材料,可以为大、小鼠提供筑巢、躲避、攀爬、休息的环境.因此,在实验大、小鼠饲养过程中,提供筑巢材料,是一个简单有效的丰富实验动物环境,提高实验动物福利的方法.本文就筑巢材料应用背景、近年来在啮齿类实验动物环境丰荣中的应用、对实验动物福利的影响三方面做以综述,并对今后筑巢材料在改善实验动物福利的应用前景作以展望.  相似文献   
32.
Abstract. 1. Oniticellus egregius Klug constructs brood ovoids of dung in the soil immediately under the edge of animal droppings. Each successive brood ovoid is enveloped within a soil shell. After completion of brood construction, loose earth is cleared from around the broods to produce a brood chamber. The immatures are then abandoned as eggs or first instar larvae.
2. O.planatus Castelnau and O.formosus Chevrolat usually construct brood balls of dung within animal droppings. Each brood is progressively enlarged by the addition of further dung after egg-laying. This enlargement is slight in O.planatus and marked in O.formosus. Parental females of both species remain in the brood chambers during development of the immatures which are abandoned principally as pupae.
3. Under very moist experimental conditions, O.planatus buries dung and constructs broods shallowly in the soil. Such nests are frequently connected to the pad by a short tunnel.
4. From a consideration of behavioural patterns it is suggested that the specialized nesting habits of these species have been derived from those of dung-burying ancestors similar to the modern genus, Euoniticellus, through reduction and loss of tunnelling in the soil.  相似文献   
33.
2002年2~6月对卧龙保护大熊猫研究中心的圈养大熊猫“雷雷”在半散放条件下的营巢行为和日摄食量的变化首次进行研究。该雌体在自然交配人工授精后一个月开始表现营巢行为。在4个月的观察过程中,大熊猫“雷雷”大约有371%的时间用于营巢或卧在巢中。营巢和卧巢的时间基本发生在上午900~1130时。营巢行为出现前后,个体的日均摄食量不存在显著差异(P=0519)。相关分析表明,日均摄食量与日营巢频次不存在显著相关关系(R=-063,P>005,n=116)。大熊猫“雷雷”总共在圈舍内3个地点营巢,最终在安全性较高、采光好而郁闭度较低的地点营巢成功。圈养大熊猫对营巢材料没有表现选择性。结果表明复杂多样、接近自然状态的圈舍可能有助于大熊猫物种特有行为的发生。研究结果对大熊猫和其它珍稀濒危动物的保护和管理工作具有一定的指导意义。  相似文献   
34.
黄腹山鹪莺的营巢特征   总被引:4,自引:1,他引:3  
营巢对鸟类的生长繁殖有着重要影响。为此,从2007年3-9月在广东省肇庆江溪村对研究地中的黄腹山鹪莺(Prinia flaviventris)的巢进行标记和测量,并以巢址为中心做5m×5m样方调查,通过主成分分析研究其巢址选择,结果表明:1)黄腹山鹪莺营巢时间始于3月中旬,4月达到高峰,至7月底结束;2)在13种植物上发现44个巢,其中在象草(Pennisetum purpureum)上最多,有27个,其次为加拿大飞蓬(Erigeron canadensis),4个,其他植物皆为1—2个;3)巢皆为不规则的球状巢,巢材除动植物性材料外,均有人工制品;巢内空间与巢整体大小较为一致;4)影响巢址选择的主要因素4种,依次为:距最近水源距离(29.89%)、距最近道路距离(16.45%)、距最近灌木距离(12.92%)、距水面高度(11.69%)。据此认为黄腹山鹪莺的营巢是对草本植物环境的适应,而其尾羽的逆向变化对营巢是有利的,起到增加飞行灵活性和减少筑巢投资的效果。  相似文献   
35.
新疆木垒波斑鸨营巢成功率的初步研究   总被引:8,自引:1,他引:7  
1998年 4月中旬~ 7月中旬 ,对分布于新疆木垒的波斑鸨 (Chlamydotisundulatamacqueenii)种群的营巢成功率进行了初步考察与研究。考察中共发现 16个巢、2 5窝幼雏。每巢产卵 3~ 6枚 ,卵鲜重 (6 4 7± 5 8)g ,卵径为 6 0 9mm× 43 9mm。产卵有两个高峰期 ,表明雌鸟第 1次繁殖失败后可再次产卵。第 1产卵期的巢卵数为(4 1± 0 8)枚 ,第 2产卵期的巢卵数为 (3 5± 0 6 )枚。雌鸟营巢成功率为 77 5 %~ 87 5 % ,卵的孵化率为83 6 %。每窝内从破壳到具备飞行能力的幼雏数基本不变 ,表明繁殖雌鸟大都能将幼雏全部抚育到可以飞行的年龄  相似文献   
36.
Abstract Numerous miniature inverted repeat transposable elements (MITEs) are present in the rice genome but their transposition mechanisms are unknown. In this report, we present evidence that two novel MITE families may have arisen from Mutator-related transposable elements and thus may use a transposition mechanism similar to that of Mutator elements. Two families of novel MITEs, namely, MDM-1 and MDM-2, were identified by searching for MITEs nested with Kiddo, a previously identified MITE family. MDM-1 and MDM-2 bear hallmarks of Mutator elements, such as long terminal inverted repeats (LTIRs), 9-bp target-site duplications (TSDs), and putative transposase binding sites. Strikingly, the MDM-1 family has a 9-bp terminus identical to that of a rice Mutator-like element (MULE-9) and the MDM-2 family has an 8-bp terminus identical to that of the maize autonomous Mutator element MuDR. A putative transposase homologous to MURA protein is identified for the MDM-2 family. Thus, these two novel MITE families, with a total copy number of several hundred in rice, are designated Mutator-derived MITEs (MDMs). Interestingly, sequence decay analysis of MDM families revealed a number of insertion site duplications (ISDs) in the alignment gaps, and widespread historical nesting events are proposed to account for the existence of these ISDs. In addition to its value for discovering new MITEs, the nesting analysis approach used in this study simultaneously identifies MITE insertion polymorphisms.  相似文献   
37.
人类休闲活动对森林鸟类群落无有害影响   总被引:1,自引:0,他引:1  
我们对西班牙马德里森林深处(未受到人类干扰)、森林小路沿线(间或有徒步旅行者经过)以及森林野餐区(有较持久干扰)的鸟类进行了调查,以查明人类休闲活动对该地区鸟类群落的分布和多度的影响.结合样方法对以上3类区域鸟类群落的总体特征(如:鸟类的多度、物种的丰富度和多样性)、不同鸟类群体的特征(如:鸦科鸟类的多度,营巢或者取食集团的特征)、各鸟种的多度等参数进行了比较.结果表明:小路沿线和野餐区样方内鸟类的多度和物种丰富度比森林深处更高,已查明14种鸟类的多度在人为干扰区域比森林深处高,只有5种鸟类的多度在森林深处更高一些;在树冠层筑巢的鸟类、在树干和地面觅食的鸟类及鸦科鸟类在休闲活动区有更高的多度;地巢性鸟类在休闲区的多度较低,这种差别尤以阔叶落叶林中加明显.而森林小路的鸟类群落结构与森林内部非常相似,说明人类休闲活动对这些林区鸟类群落的影响更多缘自野餐.原因是野餐区常常具有以下特点:具有高大的乔木、中层植被稀疏、有较多的洞和缝隙以及野餐后会遗留下一些垃圾.以上结论与研究的预期目标正好相反,人类的这些休闲活动可能会降低地巢性鸟类的适宜度,但是对大多数鸟的类栖息地没有不利影响.  相似文献   
38.
Success of species conservation depends to a large extent on comprehensive management that considers all critical aspects of a species’ niche. Many studies have examined habitat factors in relation to occurrence, abundance or foraging behaviour of European woodpecker species, while relatively little is known about nest site selection. I compared habitat structures used for nesting by middle and great spotted woodpeckers Dendrocopos medius and D. major with available structures in an oak forest in the Swiss lowlands. I first tested if nest trees were randomly selected among available trees by focusing on species, condition and diameter of nest trees, and on the presence of the fruiting body (hereafter sporophore) of polypores (wood-decomposing fungi). Second, I examined if the nesting niches of the two species were differentiated. Both species showed strong preferences for oaks, large trees, dead trees and for trees with sporophores. Nest sites of the two species differed most strongly with respect to the presence of sporophores, cavity age and tree condition, pointing towards interspecific competition for nest sites. Old living or dead trees with sporophores are central components of the nesting niche of middle and great spotted woodpeckers. Conservation plans for the threatened middle spotted woodpecker have so far mostly focused on the needs in terms of distribution and foraging; future conservation strategies and forest management must take into account the preference for dead and decaying trees with sporophores as another vital resource. This will also provide benefits for other woodpecker species as well as for the community of secondary cavity nesters.  相似文献   
39.
The interaction of a number of small organic molecules with the two lowest energy minimum conformations of [2.2.2.2]paracyclophane (4°-PCP), 1 and 2, are studied by MMP2(87) force field calculations. Formations of nesting as well as inclusion complexes were identified on the potential energy surface. With CH2Cl2 and CHCl3 used as guests, the nesting complexes are lower in energy than the inclusion ones with both conformations 1 and 2. Furthermore, the nesting complexes with 2 are found to be more stable than the nesting ones with 1. Formation of the double nesting complexes of CH2Cl2 and CHCl3 with 1 and 2 raise the difference in complexation energy in favour of 2. The preference of 4°-PCP for the form 2 in solution is explained based on the above analysis, although 2 is calculated to be 0.2 kcal·mol–1 higher in steric energy than 1 in the gas phase.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s0089490050218  相似文献   
40.
2005年2月15日~3月10日使用全方向性麦克风记录了南极地区4种企鹅(王企鹅、长眉企鹅、白眉企鹅和纹颊企鹅)的叫声,分析了其叫声的声谱图和能谱图,比较了不同种企鹅在叫声的持续时间、最高(低)频率和主频等方面的差异。通过比较发现,4种企鹅的叫声存在着明显的种间差异,这使得不同种的企鹅可以从声音上彼此区分开。而无巢企鹅(王企鹅)的声音结构比有巢企鹅(其余3种)更加复杂,这与营无巢生活的习性相符合。  相似文献   
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