摄食对印度蜓蜥代谢率的影响

通过测定摄食后印度蜓蜥雌性成体的耗氧量变化 ,研究摄食特殊热动力作用 (SDA)。动物分为摄食黄粉虫幼虫实验组和禁食对照组 ,两组蜥蜴平均体重无显著差异。测定耗氧量前 ,将所有动物在 3 0℃恒温室内禁食 3d。用容积为 3 0 0ml的封闭式呼吸室测定两组蜥蜴在 3 0℃条件下连续 3d的耗氧量 ,测定间隔时间为 4～ 2 5h。禁食组动物实验期间的耗氧量无显著的时间变异 ,实验组动物耗氧量的时间变异显著 ,这些结果表明摄食影响印度蜓蜥的代谢率。实验组动物摄食 8h后耗氧量已显著大于禁食组 ,摄食 3 0h后两组动物的耗氧量无显著差异。印度蜓蜥达到SDA峰值的平均时间约为 1 2 7h ,SDA峰值耗氧量是禁食对照组动物耗氧量的 1 6倍。印度蜓蜥单次摄食实验中的SDA具有进食后耗氧量迅速增加 ,达到峰值后下降至摄食前水平的典型模式。     

原尾蜥虎和光蜥的核型研究

该文用骨髓细胞直接制备染色体标本,分析了原尾蜥虎和光蜥的核型,原尾蜥虎２ｎ＝４６,ＮＦ＝４６,染色体组内没有划分大染色体和微小染色体的明显界限,光蜥２ｎ＝２６,ＮＦ＝４２,含４对大染色体和９对小染色体,属两性核型。二者都未发现异型性染色体。     

原尾蜥虎的生态观察

介绍原尾蜥虎的生境,摄食,冬眠,鸣叫,断尾及繁殖等生态习性。     

原尾蜥虎产卵、孵化观察

原尾蜥虎 (Ｈｅｍｉｄａｃｔｙｌｕｓｂｏｗｒｉｎｇｉｉ,Ｇｒａｙ) ,又称纵斑蜥虎[1,2 ] ,在我国主要分布于广东、海南、台湾、广西、福建等省 (区 )。在广东肇庆为一种常见的小型夜行性爬行动物 ,它喜栖息于建筑物内壁、墙缝和路灯下等场所。 1 999年 4～ 9月 ,在对本区内原尾蜥虎的生态繁殖观察研究中 ,获取了一些有关卵巢、产卵、孵化资料 ,简要报告如下。1　材料和方法本研究材料采集于本学院校园内。在实验室内将捕捉的雌雄成体按不同性比配对、标记、编号、分缸 ,用面包虫饲养在直径 2 0ｃｍ、高 2 0～ 2 5ｃｍ的玻璃缸内 (每缸不超…     

原尾蜥虎的核型和Ag-NORs研究

对原晰虎进行了核型和核仁组织者（NORs)研究,表明原尾蜥虎的2n=46,全部由23对各级大小的端着丝粒染色体组成,染色体由大至小排列,其长度依次递减,没有大染色体和小染色体的明显界限,未发现异形性染色体对。原尾蜥虎有一对Ag-NORs位于No.2的端丝粒染色体的近端区。     

体温、摄食、断尾和雌体繁殖状态对原尾蜥虎运动表现的影响

设计4项实验研究4种内外因素(环境温度、摄食、断尾和怀卵状态)导致的肇庆原尾蜥虎运动表现种群内变异.环境温度通过影响体温而影响原尾蜥虎运动表现.两性成体疾跑速均具有在低体温范围内随体温升高而加快、在高体温范围内随体温升高而降低的一般模式.在任何体温下成年雌体的疾跑速均略大于雄体,但两者平均值在统计上无显著差异.体温对原尾蜥虎最大持续运动距离的影响存在两性间差异.成年雌体的最大持续运动距离在低体温范围(从17 ℃到27 ℃)内随体温升高而增加,而在相对较高的体温范围(从27 ℃到37 ℃)内无显著变化,成年雄体在实验体温范围(从17 ℃到37 ℃)内无显著变化;在任何体温下成年雌体的最大持续运动距离均显著大于雄性.性别与体温相互作用对最大持续运动距离有显著影响.两性个体的平均疾跑速和最大持续运动距离呈显著的正相关.当去除最大持续运动距离差异的影响后发现,疾跑速两性差异统计上仍不显著.摄食、尾自切和雌体怀卵在两个实验温度下(27 ℃和31 ℃)均减小壁虎疾跑速;而仅尾自切减小壁虎的最大持续运动距离,摄食和雌体怀卵对其无影响.以上3种因子分别与体温、性别的交互作用均不显著.这些结果说明生理限制和尾自切是原尾蜥虎运动能力变异的重要来源.一些内外因素能近因性诱导蜥蜴功能表现发生一定程度的种群内变异.     

原尾蜥虎的选择体温、热耐受性和食物同化的热依赖性

(Tsel)、热耐受性和体温对食物同化的影响。Tsel无显著的日时间变化,两性个体的Tsel、临界低温(CTMin)和临界高温(CTMax)无显著的差异。Tsel、CTMin和CTMax的平均值分别为30.9℃、3.2℃和43.3℃。体温对动物食物通过时间有显著的影响。在25℃-33℃范围内,食物通过时间随体温升高而缩短;体温超过33℃后,食物通过时间随体温升高而延长。温度对原尾蜥虎的摄食量、表观消化系数(ADC)和同化效率(AE)有显著的影响。在25℃-37℃范围内,动物在低体温下(25℃和27℃)的摄食量、ADC和AE小于更高体温下动物的对应数值。种间比较结果显示,原尾蜥虎是生活于南方的蜥蜴中具有较强耐受极端体温的种类。     

广西壁虎科分布新记录--锯尾蜥虎

2005年8月11日,在对广西防城港市北仑河口国家级自然保护区野生动物进行考察时,采得壁虎科（Gekkonidae）标本1号（♀）,经鉴定为锯尾蜥虎（Hemidactylus garnotii）,属广西爬行动物新记录.报道如下.     

密点麻蜥的食性及摄食的季节性变化

分析甘肃民勤２０９只成体和４３只幼体密点麻蜥胃含物表明,密点麻蜥是以动物性食物为主的杂食性动物,主要以甲虫和白刺果为食．成体出蛰后即开始强烈摄自,摄食率均在８３％以上．食性季节性变化显著,春季仅以动物为食,夏季动物性和植物性食物各半,秋季植物性食物占１／３．食物种类多样性和营养生态位宽度随体形增大而增加．     

Feeding of Burbot, Lota lota, at Different Temperatures

Daily food intake of adult burbot, Lota lota, fed on vendace, Coregonus albula, were estimated experimentally at four different water temperatures (2.4, 5.1, 10.8 and 23.4°C). Mean daily food intake (MDI; g d^–1) and relative daily food intake (RDI; g g^–1 d^–1) increased with temperature from 2.4 to 10.8°C and decreased at 23.4°C. Temperatures of maximum daily food intake values were 13.6°C for MDI and 14.4°C for RDI. No correlation between food intake values and burbot weight was observed. RDI values were used to estimate annual food consumption of burbot population. Annual food consumption estimates were 9.7kg ha^–1 and 24.3kg ha^–1 when burbot biomass was 2.0 or 5.0kg ha^–1, respectively.     

The effects of meal size on postprandial metabolic response and post-exercise metabolic recovery process in juvenile black carp (Mylopharyngodon piceus)

The effects of meal size on the postprandial metabolic response and of digestion on the post-exercise metabolic recovery process were investigated in juvenile black carp (Mylopharyngodon piceus) . Experimental fish were forcedly fed with compound feed (meal sizes: 0.5%, 1% and 2% body weight). Then, the postprandial oxygen consumption rate and excess post-exercise oxygen consumption (EPOC) of the experimental fish were measured. Both the duration and the peak of oxygen consumption rate (PMR) increased with increasing meal size. The peak post-exercise metabolic rate of digesting fish were significantly higher, whereas EPOC magnitude and its duration were significantly smaller or (shorter) than those in the fasting fish. It is suggested that (1) this fish fulfills the increased energy demand during the digestive process by increasing PMR and by prolonging SDA duration with increasing meal size and (2) digesting fish might decrease their anaerobic exhaustive activity but increase the post-exercise recovery capacity.     

Metabolic Rate and Natural History of Ozark Cavefish, Amblyopsis Rosae, in Logan Cave, Arkansas

We investigated the effects of mass, season, and activity on oxygen consumption of the federally threatened Ozark cavefish, Amblyopsis rosae, at Logan Cave National Wildlife Refuge, Benton County, Arkansas. We used an acclimatization protocol to measure in-situ metabolic rates. There was a significant effect of mass on the metabolic rate of Ozark cavefish and this relationship differed significantly among seasons. We observed a positive relationship between mass and oxygen consumption during summer and autumn but a negative relationship for winter and spring. There was a 1°C water temperature change between summer/autumn sampling and winter/spring sampling, but it is not likely temperature alone accounted for seasonal variation in mass-oxygen consumption relationships. Activity in the respirometer did not vary significantly among seasons and was not correlated with fish mass or time of day. Seasonal relationships between mass and oxygen consumption may therefore reflect alterations in environmental conditions (i.e. food availability, ambient dissolved oxygen), condition, changes in susceptibility to handling stress, or may reflect low numbers of fish tested. Natural history observations were made throughout the study. Four females were seen in late August with ova visible in the body cavity. On 20 June 1996 we first observed five small cavefish (approximately 10 mm TL) in a pool just upstream of the sinkhole entrance that were likely less than a month old. One large adult (55 mm TL) was seen in the same pool with the young fish for six weeks, until two small fish were displaced by a storm event. Although this does not provide a clear sign of parental care, it does suggest that cannibalism is not always the rule for this species as previously suggested.     

Influence of food,body size,and fragmentation on metabolic rate in a sessile marine invertebrate

Metabolic rates vary among individuals according to food availability and phenotype, most notably body size. Disentangling size from other factors (e.g., age, reproductive status) can be difficult in some groups, but modular organisms may provide an opportunity for manipulating size experimentally. While modular organisms are increasingly used to understand metabolic scaling, the potential of feeding to alter metabolic scaling has not been explored in this group. Here, we perform a series of experiments to examine the drivers of metabolic rate in a modular marine invertebrate, the bryozoan Bugula neritina. We manipulated size and examined metabolic rate in either fed or starved individuals to test for interactions between size manipulation and food availability. Field collected colonies of unknown age showed isometric metabolic scaling, but those colonies in which size was manipulated showed allometric scaling. To further disentangle age effects from size effects, we measured metabolic rate of individuals of known age and again found allometric scaling. Metabolic rate strongly depended on access to food: starvation decreased metabolic rate by 20% and feeding increased metabolic rate by 43%. In comparison to other marine invertebrates, however, the increase in metabolic rate, as well as the duration of the increase (known as specific dynamic action, SDA), were both low. Importantly, neither starvation nor feeding altered the metabolic scaling of our colonies. Overall, we found that field‐collected individuals showed isometric metabolic scaling, whereas metabolic rate of size‐manipulated colonies scaled allometrically with body size. Thus, metabolic scaling is affected by size manipulation but not feeding in this colonial marine invertebrate.     

Elevated oxygen uptake and high rates of nitrogen excretion in early life stages of the cobia Rachycentron canadum (L.), a fast-growing subtropical fish

Physiological energetics of cobia Rachycentron canadum were quantified for 18 to 82 days post-hatch (dph) hatchery-reared juveniles to better understand energy transformation and its implications in growth and survival. Mean oxygen consumption rates ( ; mg O₂ h⁻¹) of fish fed ad libitum and fish that were starved significantly increased with increasing wet mass (M; g), = 1·4291 M ^0·8119 and = 1·1784 M ^0·7833, respectively, with a significant reduction in mean metabolic rates of starved fish (19 to 27% specific dynamic action; SDA). Total ammonia nitrogen excretion rates ( A _MM, μmol h⁻¹) also scaled with M and significantly decreased after starvation. Mean mass-specific A _MM and urea excretion rates are the highest reported in the literature, with urea accounting for approximately half the total nitrogen excretion measured in both fed and starved fish. Relatively high energetic rates may allow cobia to develop rapidly into pre-juveniles and be less susceptible to predation and starvation at a comparatively early age.     

摄食水平对瓦氏黄颡鱼餐后代谢特征的影响

以新鲜泥鳅(Misgurus anguillicanndotus)肉块为饵料,采用麻醉灌喂的方法,在(25.0±0.5)℃条件下,研究了瓦氏黄颡鱼(Pelteobagrus vachelli)幼鱼[体重(7.03±0.15)g,n=42]不同摄食水平(饵料分别为体重的0%、1%、2%、4%和8%)对餐后代谢反应的影响.结果显示,在不同摄食水平下,瓦氏黄颗鱼摄食代谢均呈现先上升后下降的整体变化趋势;摄食水平由1%增加到8%,实验鱼的SDA耗能、SDA时间和摄食代谢峰值(PMR)分别从3.09 kJ/kg、8 h和56.08 mg O_2/kg·h增加到47.21 kJ/kg、36 h和97.25 mgO_2/kg·h;其中,8%(饱足摄食水平)和4%摄食水平组的代谢率在峰值水平能够持续20 h左右.瓦氏黄颡鱼最大运动代谢率(MMR)为166.5 mg O_2/kg·h,显著大于饱食组PMR(P＜0.05).本研究还表明,随摄食水平上升,瓦氏黄颡鱼通过PMR的增加和SDA时间的延长来满足SDA耗能增加的需求;从摄食4%组和8%组相似的梯形摄食代谢曲线,可以看出瓦氏黄颡鱼在高摄食水平条件(＞4%)下限制了摄食代谢的上升;PMR相对于静止代谢上升倍率较小,暗示其摄食占据的代谢空间较小,进而保留了大量剩余代谢空间用于运动和其他生理活动,这可能与其活跃的觅食活动习性有关.     

鲤幼鱼标准代谢率的个体差异与运动性能和摄食代谢的关系

为考察鲤科鱼类种内个体标准代谢率的差异及其与运动性能和摄食性能的内在关联,本研究以我国广泛分布的鲤(Cyprinids cardio)幼鱼[体重(4.79±0.08)g,n=36]为实验对象,在(25.0±1.0)℃下分别测量实验鱼的标准代谢率(SMR),随后测定单尾鱼的特殊动力作用(SDA)、自发运动、临界游泳速度以及活跃代谢率(MO2active)。实验鱼标准代谢率(SMR)的变幅为76.7~317.6 mg/(kg·h),其变异系数(CV)达24.4%;实验鱼在10 min内的尾鳍摆动次数(P0.05)和摄食代谢峰值(P0.05)均与标准代谢率(SMR)呈正相关;活跃代谢率(MO2active)(P0.05)与摄食代谢峰值以及活跃代谢范围与摄食代谢范围(P0.05)均呈正相关。然而,鲤幼鱼的标准代谢率(SMR)与相对临界游泳速度、活跃代谢率(MO2active)、特殊动力作用(SDA)时间和特殊动力作用(SDA)总量均不相关(所有P0.05)。研究表明,较高标准代谢率(SMR)的鲤幼鱼个体表现较高的活跃性和较强的摄食代谢能力,可能有助于其更易发现食物、逃避天敌以及加快食物处理。     

食物类型对红耳滑龟幼体摄食特殊热动力作用的影响

动物通过摄食获得能量,消耗的能量主要用于基础(或标准)代谢、摄食、体温调节、运动和生长等(Bartholomew ,1 977)。食物消化、同化过程中代谢率(耗氧量)显著增加,这种增加与动物正在进行的其它活动无关,其热效应被称为特殊热动力作用(Specificdynamicaction ,SDA )或热增(Heat