温度和光周期驯化对树麻雀消化道形态特征和能量预算的影响

为探讨温度和光周期驯化对树麻雀消化道形态特征和能量预算的影响,以不同环境温度(5℃和25℃)、不同光周期(16L∶8D和8L∶16D)的4组树麻雀进行为期4周的人工气候箱驯化,并对驯化后的4组树麻雀消化道形态特征各指标以体质量为协变量,采用温度、光周期双因素协方差分析和组间进行单因素协方差分析及进行Tukey HSD比较。结果表明,温度降低或光周期缩短导致消化道长度极显著增加;反之,则缩短。温度显著影响消化道干组织质量;温度和光周期的交互作用对消化道净鲜质量和干组织质量的影响显著;总消化道和各器官的长度(直肠长度除外)、质量均存在明显的组间差异。可见,不同的温度或光周期可引起树麻雀消化道形态结构和功能能力相应的适应性变化,消化道各器官长度和质量的改变与其个体的摄能需求密切相关,消化道各器官功能能力和器官能耗之间高投资高收益的能量预算是个体适合度与环境压力之间能量预算的结果。     

风速和持续时间对树麻雀能量收支的影响

风是自然环境中常见的因子之一,会对动物的行为以及能量收支产生不同程度的影响。为探讨不同风速和持续时间对树麻雀能量收支的影响,以3种风速(0.2-0.4、1.2-1.4、3.2-3.6 m/s)和3种持续时间(1、2、4 h)的9组树麻雀进行为期1周的不同风环境驯化,测定其体重、体温和摄食量、摄水量、排泄粪量、排泄次数、摄入能、排泄粪能、排出水热能散失、消化能、同化能并计算消化率和同化率。去除初体重影响和双因素分析的结果发现,摄水量(排出水量)和排出水热能散失随着风速增大而显著减少(P < 0.001);持续时间与树麻雀的摄入能、粪能和散热调节的次数显著相关(P < 0.01),其能量收支最高和散热调节次数最多为2 h,最低(少)为4 h;双因素交互作用对树麻雀能量收支的影响不显著。3级风速(4 m/s)和持续时间4 h以内的风环境不会对树麻雀的能量收支产生显著影响。     

食物质量差异对树麻雀能量预算和消化道形态特征的影响

为比较小型鸟类对不同食物的能量预算策略,本文对3组树麻雀(Passer monanus)进行2周的食物质量差异性驯化(Acclimation)。结果表明,相同和较低的生存压力下,树麻雀体重、体温、体脂含量和水分含量表现出显著的组间差异。高能食物组摄入能和可消化能增加极显著,消化率和同化率增加不显著,体内能量储备增加;低能食物组摄入能、可消化能、消化率和同化率降低极显著,体内能量储备消耗极显著。小肠和总消化道长度以及肝脏重量出现极显著的表型可塑性响应。体内能量储备增减的预算,能量摄入和能量转化器官的功能能力与自身能耗之间的预算,以及摄食低能食物时的节能预算都是树麻雀能量预算策略的重要组成部分。总之,树麻雀对不同含能食物采用不同的能量预算策略,器官水平的表型可塑性(phenotypic plasticity)响应是个体能值出现显著变化的基础,也是个体能量预算策略成功的关键。对不同食物采用不同的能量预算策略是树麻雀重要的生存对策。     

麻雀种群数量与环境因素关系研究的某些进展

本文主要对1986年以来国外的麻雀种群数量与环境因素的关系研究作一综述。①[树]麻雀和家麻雀间存在巢穴竞争和重叠,家麻雀有更多的防御行为和数量上占优势。[树]麻雀群体繁殖第一次比单独繁殖产更多的卵,孵出更多的雏鸟,第二：、三次则相反。②农药的使用对[树]麻雀繁殖成功有一定的影响。③麻雀可以作为环境污染的指示种：家麻雀体内非正常金属元素有铝、汞、镉和铅。当铅的积累超过2μg／g干重,病、死雏鸟的比例就会增加。④在发达国家,交通可以引起麻雀死亡。     

树麻雀血清甲状腺激素的季节性变化及其对产热调节的影响

对1～2月、3～4月、5～6月、7～8月、9～10月和11～12月自然环境条件下,黑龙江齐齐哈尔地区的树麻雀Passer montanus血清中甲状腺激素的含量进行了测定,同时对其代谢产热进行了测定.结果显示树麻雀血清T3浓度在季节性驯化中具显著性的变化,于温度较高的夏季最低,于温度较低的冬春季较高.与之相伴随,树麻雀的单位体重和整体代谢率于3～4月、5～6月和7～8月较低,于1～2月和11～12月最高,表明甲状腺激素可能参与了树麻雀的产热调节.     

抗利尿素调节水代谢的生理功能

抗利尿素是由下丘脑的视上神经核和室旁神经核所形成。位于口渴中枢的前方,彼此有分布的交错。抗利尿素形成后附着于神经纤维蛋白携带体,沿着下丘脑垂体神经束往下移动,贮存于垂体后叶的微血管基膜附近,当神经冲动到达时,抗利尿素便释放出来。由於口渴中枢和调节抗利...     

饥饿驯化对树麻雀消化道长度和重量的影响

鸟类消化系统的形态结构与能量摄入密切相关.本文以相同环境中进食量充足的树麻雀(Passer montanus)为对照组,与4种处于相同饥饿环境但不同饥饿天数(1D、3D、5D、7D组)树麻雀的各消化器官的长度及重量进行比较.结果显示,饥饿驯化各组树麻雀的体重和体脂含量均低于对照组;1D组树麻雀的消化器官胃、小肠、直肠长度显著增长,重量显著增加;3D、5D、7D组各消化器官的长度和重量表现出波动的变化趋势,摄食量的限制是胃干重没有发生显著变化的原因.结论是,摄能需求的不同引起树麻雀消化器官长度和重量发生显著变化,这种变化可对摄食量及消化吸收率产生直接的影响,同时这种适应性变化应当是快速、可逆和可重复的,是消化器官形态结构与功能能力及器官自身能耗之间能量预算的结果,也是个体与环境及适合度之间能量预算的结果.     

树[鼠句]的基本实验操作方法

目的对树[鼠句]抓取和保定、采血、灌胃基本实验技术方法进行探讨,逐步规范树[鼠句]实验技术。方法选用成年树[鼠句]进行抓取和保定,分徒于法和器具法（自制捕捉保定袋）,对130只树[鼠句]采用尾静脉、股动（静）脉两种采血方法;采取人用8号胃管可对树[鼠句]绎口灌胃给药。结果所采用徒手、器具的方法抓取和保定树[鼠句]均能有效地控制动物,不会发生动物死亡或很少逃逸;两种方法都顺利采集到所需血量,股动（静）脉单次最大采血量可达2mL而不损伤动物;12只树[鼠句]连续灌胃10d,成功率100％。结论自制的捕捉保定袋经济实用,摸索的几种树[鼠句]实验技术方法具有操作简便、安全、快捷等优点。     

树麻雀肝脏和肌肉产热特征的季节性变化

北温带的小型鸟类,通过增加产热来适应低温环境.基础代谢率(BMR)是内温动物能量预算的重要组成部分.本研究中我们分别在冬季和夏季测定了树麻雀(Passer montanus)的BMR、肝脏和肌肉的线粒体蛋白含量、线粒体呼吸及细胞色素C氧化酶(COX)活力及血清中甲状腺激素(T4)及甲状腺原氨酸(T3)含量的变化.结果显示:树麻雀的体重和BMR冬季显著高于夏季;肝脏的线粒体呼吸、肝脏和肌肉的COX活力冬季较高,夏季较低;血清T3浓度冬季明显高于夏季.这些结果表明:在野外条件下,肝脏和肌肉在细胞水平产热能力的提高和血清T3含量的增加,是树麻雀抵御冬季寒冷的重要方式之一.     

银鹊树群落生物量和能量的分配

本文研究了安徽大别山天然林内16年生银鹊树和引种于南京的银鹊树幼苗及人工幼林的生物量;分析了光能利用率。研究结果表明:(1)常规芦蒹遮光;一龄苗的生物量为1777.5kg／ha。以一层塑料纱遮光处理的幼苗生物量最大;全光照的幼苗生物量居第二、三层纱遮光生物量最小。(2)天然林内16年生单株银鹊树地上部分干重为107.77kg。(3)8年生人工银鹊树林总生物量为80.63t／ha;其中乔木层平均净生产量为9.563t／ha·a;高于湖南会同、朱亭及江苏南部的杉木林。(4)银鹊树林总初级生产量为1219.18g／m2·a;其中乔木层为956.25g／m2·a;草本及天然幼苗为161.10g／m 2·a;枯枝落叶为101.83g／m2·a．光能利用率为0.527%;其中乔木层的光能利用率为0.417%。     

Thermogenic characteristics and evaporative water loss in the tree shrew (Tupaia belangeri)

Thermogenic characteristics and evaporative water loss were measured at different temperatures in Tupaia belangeri. The thermal neutral zone (TNZ) of T. belangeri was 30–35 °C. Mean body temperature was 39.76±0.27 °C and mean body mass was 100.86±9.09 g. Basal metabolic rate (BMR) was 1.38±0.03 ml O₂/g h. Average minimum thermal conductance (C_m) was 0.13±0.01 ml O₂/g h °C. Evaporative water loss in T. belangeri increased when the temperature rose; the maximal evaporative water loss was 3.88±0.41 mg H₂O/g h at 37.5 °C. The results may reflect features of small mammals in the sub-tropical plateau region: T. belangeri had high basal metabolic rate and high total thermal conductance, compared with the predicted values based on their body mass whilst their body temperatures are relatively high; T. belangeri has high levels of evaporative water loss and poor water-retention capacity. Evaporative water loss plays an important role in temperature regulation.     

树麻雀表型的环境适应进化

树麻雀(Passer montanus)分布范围广、海拔梯度大,也是人类活动的伴随物种。对中国837个样本的10个形态特征与温度、日照、海拔和风速等4个主要环境因子进行相关分析,结果显示:树麻雀的体重、嘴裂、翅长、尾长、跗跖长、脑骨宽、眼间距与日照因子显著相关(P0.05),体重、体长、翅长、尾长、跗跖长与海拔因子显著相关(P0.05),体重、嘴峰、翅长、脑骨长与温度因子显著相关(P0.05),表明树麻雀的形态指标易随环境因子的变化而变化。通过控制经度和海拔两个变量,对形态指标与纬度的偏相关分析表明,体重、翅长、脑骨长和脑骨宽与纬度呈显著正相关(P0.05),体表突出部分嘴峰、嘴裂与纬度呈显著负相关(P0.05),即随着纬度的升高,树麻雀身体逐渐变大,符合贝格曼规律;体表突出部分嘴峰和嘴裂随纬度升高变短,符合阿伦规律。飞行能力与海拔因子呈极显著正相关(n=92,r=0.217,P=0.038),表明树麻雀在高海拔地区具有更强的飞行能力,这也许是它成为广布种的重要原因。     

Evaporative water loss and energy metabolic in two small mammals,voles (Eothenomys miletus) and mice (Apodemus chevrieri), in Hengduan mountains region

Evaporative water loss (EWL) and energy metabolism were measured at different temperatures in Eothenomys miletus and Apodemus chevrieri in dry air. The thermal neutral zone (TNZ) of E. miletus was 22.5–30 °C and that of A. chevrieri was 20–27.5 °C. Mean body temperatures of the two species were 35.75±0.5 and 36.54±0.61 °C. Basal metabolic rates (BMR) were 1.92±0.17 and 2.7±0.5 ml O₂/g h, respectively. Average minimum thermal conductance (C_m) were 0.23±0.08 and 0.25±0.06 ml O₂/g h °C. EWL in E. miletus and A. chevrieri increased with the increase in temperature; the maximal EWL at 35 °C was 4.78±0.6 mg H₂O/g h in E. miletus, and 5.92±0.43 mg H₂O/g h in A. chevrieri. Percentage of evaporative heat loss to total heat production (EHL/HP) increased with the increase in temperature; the maximal EHL/HP was 22.45% at 30 °C in E. miletus, and in A. chevrieri it was 19.96% at 27.5 °C. The results may reflect features of small rodents in the Hengduan mountains region: both E. miletus and A. chevrieri have high levels of BMR and high levels of total thermal conductance, compared with the predicted values based on their body masses, while their body temperatures are relatively low. EWL plays an important role in temperature regulation.     

Genetic variation and relationships in Laetiporus sulphureus s. lat., as determined by ITS rDNA sequences and in vitro growth rate

The aim of this study was to characterise the genetic variation and molecular relationships of the brown rot polypore, Laetiporus sulphureus s. lat., from Europe, South America, Africa, and Asia, using ITS sequences of the nu-rDNA and by comparing the growth rate in vitro. In a NJ analysis of the sequences of 130 individuals of L. sulphureus s. lat., eight distinct clusters emerged, supported by BS values of 70-100 %. Within each cluster, the ITS rDNA sequence variation was below 3 %. The sequences were also analysed together with Laetiporus sequences available from GenBank. Results demonstrated the possible presence of L. huroniensis in Europe (invalidly named L. montanus) and L. gilbertsonii in South America, and provided more information on the Pan-American and European distribution of one of the clades, currently known in North America as L. sulphureus. L. conifericola formed a separate distinct clade. Moreover, the analysis revealed two unknown Laetiporus taxa in Korea, one in South Africa, and one in Europe. As L. sulphureus is described from Europe (France), and we show that more than one taxon exist here, it is presently not possible to define L. sulphureus s. str. Certain biological differences between some of the clades (in vitro growth rates, chemical composition, and pigmentation) were demonstrated and discussed.     

Habitat use of urban Tree Sparrows in the process of urbanization: Beijing as a case study

The Tree Sparrow (Passer montanus) is a dominant species in urban bird communities. With the development of urbanization, the habitats and sources of food for Tree Sparrows are decreasing. Can the urban Tree Sparrow adapt to changes in the urban environment? To answer this question, we studied the habitat use of Tree Sparrows in eight types of urban areas in Beijing. The results show that the number of both breeding and wintering Tree Sparrows decreased with increasing urbanization. The habitat use of Tree Sparrows, analyzed using stepwise discriminant analysis, was positively correlated with the number of brick bungalows, coniferous and broad-leaved trees and air conditioners. It was negatively correlated with the area of high buildings and hardened roads, pedestrian and automobile flux. This indicates that the Tree Sparrow had not adapted to rapid urbanization even though it is a generally adaptable species. Urban planning should take birds such as the Tree Sparrow into consideration. __________ Translated from Biodiversity Science, 2006, 14(5): 372–381 [译自:生物多样性]     

Impaired hatching success and male-biased embryo mortality in Tree Sparrows

During the past 30 years, many species of farmland birds have declined dramatically in numbers in Northern Europe, a trend coinciding with a tremendous intensification of agriculture, although the exact causes of these declines remain unclear. One of the worst affected species is the Tree Sparrow (Passer montanus). We studied two Swedish Tree Sparrow populations during the years 1996–2004 and found that in both populations, almost half of all laid eggs remained unhatched. This led us to investigate whether the eggs failed to hatch because of: (1) eggs not being fertilised or (2) embryo mortality. Our analyses showed that all of the eggs investigated contained sufficient number of sperm for fertilisation and that they also had other visible signs indicating that fertilisation had occurred. Hatching failure was instead shown to result from embryo mortality. Using molecular techniques, we were able to determine that embryo mortality is more likely to affect male embryos than females and that the fledgling sex ratio was consequently highly female biased. The cause of this sex-biased embryo mortality remains unknown, but various potential explanations are discussed.