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1.
以成都动物园人工饲养的7条湾鳄Crocodylus porosus Schneider为对象,介绍了在人工饲养条件下经常会用到的抓捕、采血、性别鉴定等技术操作及其意义,为湾鳄的人工饲养管理提供一定的实践依据.  相似文献   

2.
常敏毅 《化石》2002,(2):24-24
埃及的木乃伊 ,被考古学家挖出研究的不下五万具。1851年 ,法国考古学家奥丘斯·马里埃在开罗近郊的地下 ,发掘出了一座巨大的陵墓。陵墓是用精工磨制的黑红相间的花岗岩砌成的。在数千斤重的石棺中 ,人们惊奇地看到一具牛的木乃伊卧在其中。大约5000年前 ,埃及人把努比亚野生猫和山猫杂交 ,得到了新变种。由于新种猫特别能吃老鼠 ,所以受到埃及人的保护和崇拜 ,在神殿里铸造了各种神态的青铜猫。猫死了 ,还要制成木乃伊 ,涂以香料 ,隆重下葬。1860年 ,在埃及的别尼哈桑发现了古埃及的猫的墓地 ,这里竟埋葬着18万只猫的木乃伊…  相似文献   

3.
概述了鳄类动物的繁殖生物学特性。对在其它爬行动物中不多见,而在鳄类中普遍存在的亲体关怀行为和孵化温度决定后代性别的现象进行了阐述。并从生态学和进化论角度,对这些现象进行了讨论。  相似文献   

4.
本文简介了分支系统学意义上的鳄型动物(CrocodylomorphaWalker.1970)的组成。首次应用分支系统学方法讨论了重庆西蜀鳄的系统发有关系。本文的结论否定了西蜀鳄和西贝鳄类系统关系相近的论点,并认为前者比后者要原始得多,它是Mesoeucrocodylia中最原始的代表之一。  相似文献   

5.
本文报道了1997~1998年湾鳄(Crocodylusporosus)的人工孵化工作,并通过对比试验确定了鳄卵孵化的最适温度、湿度以及最佳的覆盖巢材和鳄卵在孵化盘中的正确摆放方位。获得受精卵总孵化率为86-8%。1 材料方法试验用卵取自深圳市野生动物园湾鳄产下的卵。将所有收集到的未破损的受精卵分成2组,一组为湾鳄在人工设置的产卵间内自然营巢产的卵,按母鳄产卵时自然摆放的方位放入盛卵盘内作为正放组;另一组为没有营巢环境而产于水泥地或草地上的滚动过的卵作为对照组。2 结 果2-1 1997年有3条…  相似文献   

6.
鳄与人     
“看,它冲出菖蒲和芦苇丛,腹部滚圆,高高地甩着那满是褶皱的尾巴,漂浮在湖面上。血盆大口处,水流如瀑;宽阔鼻孔中,雾气滚滚。大地在它脚下颤抖,发出雷鸣般的声音。”  相似文献   

7.
鳄类的取食和繁殖行为   总被引:2,自引:0,他引:2  
张峰 《生物学通报》2001,36(8):9-11
鳄类是现代爬行动物中身体结构最高级的动物,就其捕食,求偶与交配,营巢与产卵,护巢,挖巢和护幼等行为进行了介绍。  相似文献   

8.
湾鳄采食量活动性季节变化与环境温度的关系   总被引:3,自引:0,他引:3       下载免费PDF全文
湾鳄是外热动物,其采食量及活动规律受环境温度的影响极为明显,呈现苏醒期、发情期、产蛋繁殖期(盛食期),越冬准确期,越冬期等季节性周期现象。越冬期人工保温,是提高湾鳄成活率的关键。  相似文献   

9.
<正>许多人问道:"怎么会有人对保护鳄鱼感兴趣?它们的相貌那么可怕、邪恶,还富有攻击性,为什么还要保护它们呢?"其实,鳄类是地球上现存的几种最令人称奇的动物之一,是除海洋生物以外世界上最大的食肉动物,它们当中有些种类身长超过6米,体重超过1吨。一条成年鳄类在水中可以与一匹成年斑马抗  相似文献   

10.
一龄内扬子鳄的饲养和管理技术的改进   总被引:4,自引:1,他引:3       下载免费PDF全文
对扬子鳄幼鳄的饲养与管理技术进行了改进,经过1996-1998年计5000多条幼鳄的饲养实践,总结出新的饲养与管理技术,对提高幼鳄的成活具有极为显著的效果,8月龄成活率可达95%左右,14月龄成活率90%左右。  相似文献   

11.
Temperature probes were inserted into the stomachs of juvenile American alligators (Alligator mississippiensis) maintained outdoors at ambient fluctuating temperatures. Internal body temperatures (Tb) were measured every 15 min for two days, and then the alligators were injected with bacterial lipopolysaccharide (LPS), pyrogen-free saline, or left untreated. Alligators injected intraperitoneally with LPS exhibited maximum Tbs 2.6 ± 1.1 °C and 3.5 ± 1.2 °C higher than untreated control animals on days one and two after treatment, respectively. Tbs for these animals fell to within control ranges by day three postinjection. Similarly, mean preferred body temperatures (MPBTs) were significantly higher for LPS-injected alligators on days one (4.2 ± 1.8 °C) and two (3.5 ± 1.6 °C) after treatment. Intraperitoneal injection of heat-killed Aeromonas hydrophila, a gram-negative bacterium known to infect crocodilians, resulted in a fever while injection of Staphylococcus aureus (gram positive) did not elicit a febrile response. Injection of LPS in alligators maintained indoors in a constant temperature environment resulted in no increase in internal Tb. These results indicate that alligators did not exhibit a febrile response in the absence of a thermal gradient, and suggest that febrile responses observed are probably behavioral in nature.  相似文献   

12.
Microsatellite DNA loci have emerged as the dominant genetic tool for addressing questions associated with genetic diversity in many wildlife species, including crocodilians. Despite their usefulness, their isolation and development can be costly, as well as labour intensive, limiting their wider use in many crocodilian species. In this study, we investigate the cross-species amplification success of 82 existing microsatellites previously isolated for the saltwater crocodile (Crocodylus porosus) in 18 non-target crocodilian species; Alligator sinensis, Caiman crocodylus, Caiman latirostris, Caiman yacare, Melanosuchus niger, Paleosuchus palpebrosus, Crocodylus acutus, Mecistops cataphractus, Crocodylus intermedius, Crocodylus johnstoni, Crocodylus mindorensis, Crocodylus moreletii, Crocodylus niloticus, Crocodylus novaeguineae, Crocodylus palustis, Crocodylus rhombifer, Crocodylus siamensis, and Osteolaemus tetraspis. Our results show a high level of microsatellites cross-amplification making available polymorphic markers for a range of crocodilian species previously lacking informative genetic markers.  相似文献   

13.
Blood was collected from three juvenile alligators (Alligator mississippiensis) before, and again 24 h after, injection with bacterial lipopolysaccharide (LPS). The leukocytes were collected from both samples, and the proteins were extracted. Each group of proteins was labeled with a different fluorescent dye and the differences in protein expression were analyzed by two dimensional differential in-gel expressions (2D-DIGE). The proteins which appeared to be increased or decreased by treatment with LPS were selected and analyzed by MALDI-TOF to determine mass and LC–MS/MS to acquire the partial protein sequences. The peptide sequences were compared to the NCBI protein sequence database to determine homology with other sequences from other species. Several proteins of interest appeared to be increased upon LPS stimulation. Proteins with homology to human transgelin-2, fish glucose-6-phosphate dehydrogenase, amphibian α-enolase, alligator lactate dehydrogenase, fish ubiquitin-activating enzyme, and fungal β-tubulin were also increased after LPS injection. Proteins with homology to fish vimentin 4, murine heterogeneous nuclear ribonucleoprotein A3, and avian calreticulin were found to be decreased in response to LPS. In addition, five proteins, four of which were up-regulated (827, 560, 512, and 650%) and one that exhibited repressed expression (307%), did not show homology to any protein in the database, and thus may represent newly discovered proteins. We are using this biochemical approach to isolate and characterize alligator proteins with potential relevant immune function.  相似文献   

14.
    
We employed a spectroscopic assay, based on the hemolysis of sheep red blood cells (SRBCs), to assess the innate immune function of saltwater and freshwater crocodiles in vitro. Incubation of serum from freshwater and saltwater crocodiles with SRBCs resulted in concentration-dependent increases in SRBC hemolysis. The hemolytic activity occurred rapidly, with detectable activity within 2 min and maximum activity at 20 min. These activities, in both crocodilian species, were heat sensitive, unaffected by 20 mM methylamine, and completely inhibited by low concentrations of EDTA, suggesting that the alternative serum complement cascade is responsible for the observed effects. The hemolytic activities of the sera were inhibited by other chelators of divalent metal ions, such as phosphate and citrate. The inhibition of SRBC hemolysis by EDTA could be completely restored by the addition of 10 mM Ca2+ or Mg2+, but not Ba2+, Cu2+ or Fe2+, indicating specificity for these metal ions. The serum complement activities of both crocodilians were temperature-dependent, with peak activities occurring at 25-30 degrees C and reduced activities below 25 degrees C and above 35 degrees C.  相似文献   

15.
    
This study investigated growth, condition and development of American eels Anguilla rostrata that were introduced into a European river to estimate their competitive potential in a non‐native habitat. Results demonstrate that A. rostrata develops normally in European waters and successfully competes with the native European eel Anguilla anguilla. In addition, A. rostrata appears to be more susceptible to the Asian swimbladder nematode Anguillicola crassus than A. anguilla and could support the further propagation of this parasite. Detected differences in fat content and gonad mass between Anguilla species are assumed to reflect species‐specific adaptations to spawning migration distances. This study indicates that A. rostrata is a potential competitor for the native fauna in European fresh waters and suggests strict import regulations to prevent additional pressure on A. anguilla and a potential further deterioration of its stock situation.  相似文献   

16.
    
Coprolites can preserve a wide range of biogenic components. Of all the coprolites known from the fossil record, hitherto only two are known to preserve vertebrate tooth impressions (i.e., those of chondrichthyans). Here, a coprolite, from a thick lag deposit that includes a mixture of late Cretaceous, early Paleocene, and Plio-Pleistocene taxa at Clapp Creek in Kingstree, Williamsburg County, South Carolina, USA, preserves bite marks most consistent with having been made by a gar, Lepisosteus sp. (Lepisosteidae, Actinopterygii). This is the first-known coprolite to preserve actinopterygian tooth/bite marks. Aborted coprophagy seems unlikely; an accidental or serendipitous strike more likely describes the origin of the score marks over the surface of the coprolite. This coprolite also preserves small paired striations interpreted as evidence of coprophagy by an unknown organism.  相似文献   

17.
    
《Current biology : CB》2022,32(5):999-1009.e9
  相似文献   

18.
19.
International trade transfers social and environmental impacts across national borders. The consumption of forest products often takes place far away from industrial production sites, and mills procure raw material from remote forests. Finland produces about 10% of forest products that are traded internationally, with the majority of its exports destined for other European countries. Here we report and analyze data that demonstrate that international leakage, in relative terms, increased faster than the production of commodities. The international consumption of products made in Finland increased, and an increase in wood imports from Russia provided the raw material for most of the incremental production. The international consumption‐production system translated the increasing global demand for Finnish products into increased harvests in Russia, until the Russian customs duties started to increase in 2007. We argue that national and regional policies for the promotion of sustainable consumption and production must be analyzed and assessed from an international, holistic perspective.  相似文献   

20.
几种鳄分子系统发生的探讨   总被引:4,自引:0,他引:4  
朱伟铨  王义权  吴孝兵  周开亚 《遗传》2001,23(5):435-438
百年来关于扬子鳄的分类学位置存在着很多争议,本测得扬子鳄、暹罗鳄和湾鳄的mtDNA ND4和Cytb基因,并从GenBank中获得密西西比鳄和海龟的DN4基因和Cytb基因相应片段。用Clustal X1.8进行对位排列,以海龟为外群构建分子进化系统树。结果显示,在鳄类动物中,扬子鳄与密西西比鳄的亲缘关系最近,两ND4基因序列碱基差异的20.68%,而Cytb基因序列碱基差异为14.43%,但扬子鳄与密西西相比与鳄的分类问题仍将有待进一步探讨。  相似文献   

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