葡萄糖和维生素C对普安银鲫卵黄囊仔鱼ACC、FAS及CPTⅠ活性的影响

本试验旨在探究普安银鲫(Carassius auratus )卵黄囊仔鱼发育过程中ACC、FAS及CPT I活性变化及葡萄糖和维生素C溶液分别浸泡对它们的影响。采用酶学方法研究了普安银鲫卵黄囊仔鱼过程中ACC、FAS及CPT I活性变化的变化特点。结果显示：在卵黄囊仔鱼发育过程中,对照组与维生素C组中ACC和FAS活性呈上升趋势,CPT I活性呈“下降-上升”变化趋势,而葡萄糖组ACC、FAS及CPT I活性均呈上升趋势,且3种酶的活性均显著高于对照组(P<0.05)。维生素C组ACC活性在内源营养期显著高于对照组,FAS活性在混合营养期和外源营养期显著高于对照组,CPT I活性在内源营养期和外源营养期显著高于对照组(P<0.05)。研究表明：ACC、FAS及CPT I在维持普安银鲫卵黄囊仔鱼发育中脂质代谢的动态平衡起着重要作用,15g/L的葡萄糖溶液可通过调节仔鱼体内脂质代谢酶的活性而形成新的脂质代谢水平,以满足仔鱼生长发育需要;而30mg/L的维生素C对维持仔鱼发育中体内正常的脂质代谢具有重要作用。     

锦鲫幼鱼标准代谢率与生长性能的关联

为考察温水性鲤科鱼类在不同食物资源条件下标准代谢率(Standard metabolic rate, SMR)与其生长性能的关系, 研究在(25.00.5)℃条件下测定体重相近的30尾锦鲫(Carassius auratus)幼鱼的SMR, 将所有实验鱼置于多单元格水槽进行实验处理(摄食与饥饿)。实验时间为4周(0、7d、14d、21d和28d), 包括两周的生长实验(014d)和两周的饥饿实验(1528d)。摄食期间, 于每天上午9: 00和下午21: 00用商业饲料对每尾鱼饱足投喂并记录投喂量。单尾鱼的体重和体长每隔1周测定一次, 而SMR仅在第0、第14和第28天测定。结果显示:(1)锦鲫幼鱼在摄食期间的体重、体长以及SMR均明显上升, 饥饿期间体重和SMR显著降低(P0.05), 但体长变化不明显; SMR不论摄食期间还是饥饿期间呈现较好的稳定性(二者P0.05)。(2)锦鲫幼鱼在摄食期间开始时的SMR (测定Ⅰ)与摄食率(FR)、摄食转化率(FE)以及特定体重生长率(SGRBM)均无相关性, 摄食期间结束时的SMR (测定Ⅱ)仅与FR呈正相关(P0.05), 但与FE以及SGRBM不相关。(3)摄食期间(饥饿期间)实验鱼的第一周日均体重增(减)量与第二周日均体重增(减)量呈正相关, 其体重的增率与减率无显著差异(P0.05)。(4)实验鱼在摄食期间的特定体重增长率(SGRBM)与饥饿期间的不相关(P0.05), 但摄食期间的特定SMR增长率(SGRSMR)与饥饿期间的呈负相关(P0.05)。研究表明在实验室环境中锦鲫幼鱼的SMR具有稳定性, 该种鱼的日均体重变化量保持相近, 此形态变化特征与SMR不相关, 并且该种鱼在实验起始时的SMR的个体差异未能预测其在实验室食物资源变动下生长性能的适应特征。     

Hydrodynamic Analysis of C-start in Crucian Carp

The kinematics of turning maneuvers of startled Crucian Carp (Carassius auratus) are presented. All escape response observed are C-type fast-starts. The position of the center of mass and the me,merit of inertia of the fish are calculated. The results show that the position of the center of mass is always at 35% of the length of the fish from the head and the position of the center of mass and rroment of inertia can be considered unchanged during C-start of Crucian Carp. Hydro-dynamic analysis of the C-start is given based on the kinematics data from our experiments. The C-start consists of three stages. In stage 1, the tail fin of fish rapidly flaps in one direction, and a large moment acts on the fish‘s body, which rotates around the center of mass with an angular acceleration. In stage 2, the tail fin flaps more slowly in the opposite direction at slower speed, the fish‘s body rotates around the center of mass with angular deceleration and the center of mass of the fish moves along an are. In stage 3, the moment approximately equals zero, the fish‘s body stops rotating and the center of mass the moves along a straight line.     

Effects of salmon calcitonin and anti-salmon calcitonin antibody on plasma calcium concentrations in the goldfish,Carassius auratus

The role of calcitonin (CT) in plasma calcium regulation was studied by the administration of exogenous CT and anti-salmon(s) CT antibody using goldfish,Carasius auratus, loaded or otherwise with calcium. CT elicited a decrease in plasma calcium concentrations at a dose of 10 ng/g body weight 1 h after administration. However, no effects were observed following doses of 30 ng and 50 ng/g 1 h, nor for the three doses 3 h after administration. In calcium-loaded fish, the effect of CT was different depending on the dosage of CT. Ten ng and 50 ng/g induced a decrease and an increase in plasma calcium concentrations, respectively, 3 h after administration. Anti-sCT antibody (0.02 μg or 0.1 μg/g) did not affect plasma calcium concentrations. In calcium-loaded fish, neither dose of anti-sCT antibody changed plasma calcium concentrations 1 h after administration. However, following a dose of 0.1 μg/g, plasma calcium concentrations decreased after 3 h. A positive correlation between plasma calcium concentrations and the gonad somatic index (GSI) in females was no longer apparent after administration of anti-sCT antibody. There was no relationship between plasma calcium concentrations and GSI in control and anti-sCT antibody-treated males. These results suggested that CT regulates plasma calcium concentrations in different ways depending on the dosage with CT having a role in calcium physiology during vitellogenesis.     

江豚鳍肢骨骼形态特征的观察

江豚Neophocaena phocaenoides鳍肢的基本结构与海洋豚类相同,但又有其特殊性。为完善江豚鳍肢骨骼形态特征的研究,本文通过运用原位解剖、制作透明鳍肢骨骼以及X光拍照的方法,对威海海域四头江豚的鳍肢骨骼进行了较全面、较系统地观察和测量,对每一块骨骼的名称、位置、形状、大小做了详细描述,并分析了没有中央腕骨和腕骨1的原因,这些在以往的研究中还未见报道。标本具有不同的年龄和性别,采集的时间和地点也不同,因此,本结果带有一定的普遍性。与以往研究鳍肢骨骼的方法相比,制作透明鳍肢骨骼具有直观、完整、清晰、美观、准确、易于观察等特点,辅以X光照片观察得出与以往研究的结果有很大差别,如国内外学者原来记述腕骨的形态为5块相连成一平坦的椭圆形盘状;指式总结为:Ⅰ2-3,Ⅱ5-9,Ⅲ5-8,Ⅳ3-4,Ⅴ2-3。而作者记述为在整体上,腕骨与包围它们自身的软骨共同连成一平坦的不规则多角形;指式为:Ⅰ0-1,Ⅱ6,Ⅲ5,Ⅳ2,Ⅴ0(掌骨不计)。据分析,造成这些差异的主要原因之一是研究方法的不同。       

Habitat-Suitability Models for Cavity-Nesting Birds in a Postfire Landscape

ABSTRACT Models of habitat suitability in postfire landscapes are needed by land managers to make timely decisions regarding postfire timber harvest and other management activities. Many species of cavity-nesting birds are dependent on postfire landscapes for breeding and other aspects of their life history and are responsive to postfire management activities (e.g., timber harvest). In addition, several cavity nesters are designated as species at risk. We compare the ability of 2 types of models to distinguish between nest and non-nest locations of 6 cavity-nesting bird species (Lewis's woodpecker [Melanerpes lewis], black-backed woodpecker [Picoides arcticus], hairy woodpecker [P. villosus], northern flicker [Colaptes auratus], western bluebird [Sialia mexicana], and mountain bluebird [S. currucoides]) in the early postfire years for a ponderosa pine (Pinus ponderosa) forest in Idaho, USA. The 2 model sets consisted of 1) models based on readily available remotely sensed data and 2) models containing field-collected data in addition to remotely sensed data (combination models). We evaluated models of nesting habitat by quantifying the model's ability to correctly identify nest and non-nest locations and by determining the percentage of correctly identified nest locations. Additionally, we developed relative habitat-suitability maps for nesting habitat of black-backed and Lewis's woodpeckers from the best models. For all species except Lewis's woodpeckers, model performance improved with the addition of field-collected data. Models containing remotely sensed data adequately distinguished between nest and non-nest locations for black-backed woodpecker and Lewis's woodpecker only, whereas models containing both field-collected and remotely sensed data were adequate for all 6 species. Improvements in the availability of more accurate remote sensing technology would likely lead to improvements in the ability of the models to predict nesting locations. External validation with data from other wildfires is necessary to confirm the general applicability of our habitat-suitability models to other forests. Land managers responsible for maintaining habitat for cavity-nesting birds in postfire landscapes can use these models to identify potential nesting areas for these species and select areas in burned forests where postfire salvage logging is most likely to have minimal impacts on cavity-nesting bird habitats.     

基于Maxent的两种入侵性鱼类(麦穗鱼和鲫)的全球适生区预测

受引种、贸易等人类活动的影响, 麦穗鱼(Pseudorasbora parva)和鲫(Carassius auratus)在全球范围内已经广泛分布并造成巨大的生态危害。根据野外采样和文献记录, 本文系统整理了麦穗鱼和鲫在世界各地的分布情况, 以高达2.5弧分分辨率的环境数据底图, 利用Maxent模型预测了麦穗鱼和鲫在全球的适生区, 以期为防控麦穗鱼和鲫的入侵提供早期预警。结果表明麦穗鱼和鲫在全球范围的分布区非常广泛, 除南极洲外的各个大洲均有其适生区, 因此这两种鱼还有继续扩散的潜力, 并可能在美国、巴西和阿根廷等国家出现由生物入侵导致的生态学问题。麦穗鱼的适生区主要集中在15º–55º N之间, 欧洲是麦穗鱼入侵的重灾区, 尤其是法国、荷兰周边的西欧国家和匈牙利、塞尔维亚周边的东欧国家; 而美国中部的密西西比河流域、东部及南部沿海, 以及西雅图至加拿大的温哥华之间是麦穗鱼潜在入侵风险性极高的区域。鲫自然分布于欧洲至东亚的广大地区, 目前已经在澳大利亚、加拿大、美国、马达加斯加、印度和越南等国家有分布, 未来还可能进一步扩散至大洋洲的新西兰和新喀里多尼亚, 北美洲的墨西哥至南美洲的阿根廷, 以及非洲的塞内加尔、几内亚和南非等国家; 尤其是南美洲的阿根廷和巴西, 非洲西部的几内亚、喀麦隆等国家将是鲫入侵风险极高的区域。     

HRP技术对鲫鱼尾部神经分泌系统的研究

本实验采用辣根过氧化物酶（HRP）逆行追踪技术对鲫鱼尾部神经分泌系统进行了研究,结果表明,尾部神经分泌细胞可分为大（60－70μm）、中（40－50μm）、小（20－30μm）三种类型,在尾部脊髓的背侧面和腹侧面都有分布,HRP的引入采用Griffin（1979）提出的缓释胶法,结果证明这种方法在鱼类神经解剖的束路示踪方而是可行的。     

鲫鱼后鳃体结构与功能的研究

本文对鲫鱼后鳃体的形态结构及其功能进行了初步研究。结果表明,鲫鱼后鳃体是一种内分泌腺体。腺体由滤泡组成,滤泡上皮包括二种颗粒细胞(亮细胞和暗细胞)和一种支持细胞。对不同性腺期的鲫鱼后鳃体的观察表明,后鳃体滤泡细胞随性腺发育增加高度,滤泡增生,腺体体积增大。而性腺成熟后期,后鳃体滤泡上皮有崩溃现象。揭示后鳃体可能与性腺发育有关。用免疫组织化学的非标记过氧化物酶技术对鲫鱼后鳃体进行激素降钙素的定性定位研究,观察到滤泡上皮的颗粒细胞发生阳性反应,由此证明颗粒细胞可分泌降钙素。     

鲫鱼金属硫蛋白的提纯及性质研究

用氯化镉诱导鲫鱼(Carassius aurattus),应用层析介质 Sephacryl S 体系从鱼肝脏中提取金属硫蛋白(MT),并对其性质进行研究.实验表明鲫鱼 MT 的性质与哺乳动物 MT 的性质十分相似.分子量约10 000,含丰富的半胱氨酸,较多的赖氨酸,不含芳香族氨基酸.紫外250nm 处强吸收,280nm 处几乎没有吸收。鱼 MT 含7个金属每分子,并含有20个巯基.测得鲫鱼 MT 等电点 pI 在5.6左右.