观赏鱼

观赏鱼多姿多彩,从我国饲养观赏鱼概况、常见的几种观赏鱼、观赏鱼的饲养、与人类关系4方面介绍观赏鱼。     

养殖观赏鱼生态系统

观赏鱼是大家比较熟悉的动物 ,通过对观赏鱼养殖生态的讨论 ,可以从相对简单的养殖观赏鱼水簇箱生态系统来增进对大自然生态平衡的认识。1　观赏鱼水簇箱生态系统观赏鱼水簇箱生态系统的主要组成有生物因子 ,包括鱼、水草及其中的一些微生物等 ;非生物因子有水中的各种化学和物理因子 ,以及与水体直接接触的空气等。要养好观赏鱼 ,除鱼本身外 ,其中最主要的几个条件是足够的食物、合适的水温、水中维持较高的溶氧、一定的透明度以及水中较低的二氧化碳、氨氮和病原微生物。2　水簇箱生态系统中各因子的相互作用当生态系统中各物质的变化能达…     

多姿多彩的观赏鱼文化

<正>观赏鱼以它的艳丽体色、奇特体态、多样习性而受到人们的喜爱。它们多生活在温带、亚热带及热带,我国有观赏鱼250多种,其中有被誉为"国鱼"的金鱼,有近些年获得观赏鱼大赛的长薄鳅、胭脂鱼,有引进的锦鲤、热带鱼等。金鱼(古名:金鲫鱼、盆鱼、三尾鱼、朱砂鱼、赤鳞鱼等)为我国观赏鱼中的"国鱼",是从野生金鲫鱼培育而成。     

线粒体COⅠ基因在观赏鱼中物种鉴定与分类应用

观赏鱼种类繁多,形态各异,市场上多是以商品名命名,在物种鉴定分类上存在一定的难度。本研究基于线粒体COⅠ基因,探讨其在观赏鱼中物种鉴定与分类应用的可行性。通过PCR扩增,获取18种观赏鱼249个个体的COⅠ基因序列。基于Kimura双参数模型,利用MEGA软件计算18种观赏鱼种间和种内遗传距离,并构建系统进化树。结果显示,观赏鱼类的种间遗传距离明显大于种内遗传距离,线粒体COⅠ基因序列可以用于物种鉴定。在系统进化树中,系统进化关系跟传统分类方法所得数据一致性高。研究表明,观赏鱼线粒体COⅠ基因序列,在物种鉴定与进化分类上具有一定的应用价值。     

观赏鱼

观赏鱼庄琰，张世义（中国科学院动物研究所北京１０００８０）观赏鱼的体色艳丽、体态婀娜、外形奇特、习性有趣，具有较高的欣赏价值，深受人们的喜爱，被视为宠物。１观赏鱼的家族１．１观赏鱼的分布及饲养历史观赏鱼的种类繁多，分布较广，其中热带鱼约有２０００种，...     

寄“鱼”厚望——走近生物学家的“宠物”斑马鱼

美国得克萨斯州一家公司不久前宣布,他们很快会开始出售一种能够在黑夜中发光的转基因观赏鱼,并预测这将会让许多人,特别是观赏鱼爱好者一族大感兴奋。据《纽约时报》报道,这种被命名为"发光鱼"的转基因观赏     

龙鱼

近几年来,热带观赏鱼的种类,增添了新品种——龙鱼。龙鱼受到人们的喜爱,并不在于“新”,而在于奇。它那威武奇特的嘴脸,细长的胡须,体色银光粼粼。龙鱼适应性强。生活力更强,水温降到8℃,其他的热带观赏鱼已相继死亡,可是它仍能生存一段时间。而且龙鱼的食性很杂,荤素均可。龙鱼的繁殖方式很怪。其他热带观赏鱼大多产于水草上孵化,可它把卵产出后,吞进口里慢慢孵化。历经一月之久,才将其孵出幼鱼从口中吐出。目前的龙鱼品种有“巴西银龙鱼”,“巴西黑龙鱼”、“马来西亚金龙鱼”、“马来西亚青金龙鱼”“印度尼西亚红龙鱼”、“印度尼西亚红尾金龙鱼”及“澳大利亚神龙鱼”等。     

养殖热带鱼学问多

有时候人们会把观赏鱼和热带鱼混为一谈,对于养鱼的人来说这是不应该的,如果连自己养的鱼到底属于哪一类都不清楚,要想养好它是不太可能的,更无法与同行交流。所谓观赏鱼,是指人们为欣赏或装饰而养殖的鱼,所以,只要是能在家庭长时间养殖、有欣赏价值的鱼类     

“灭非灵”对观赏鱼养殖池塘中外来种尼罗罗非鱼的杀灭效果

为有效清除观赏鱼养殖中混入的外来物种尼罗罗非鱼(Oreochromis niloticus),减少其对养殖品种生长和繁殖的干扰,增加养殖效益,本研究利用大型观赏鱼池塘,通过两次投放0.16 mg·L~(-1)的"灭非灵",对罗非鱼特异性杀灭药物"灭非灵"的杀灭效果进行了验证试验。结果表明:该浓度的"灭非灵"能有效清除池塘中的罗非鱼个体,清除率达到99%以上;且能将该药物对其他物种的危害降到最低,在实验过程中,未发现对池塘中的多个养殖种产生影响,取得了特异性杀除罗非鱼的效果。与以往在实验室内的验证相比,本次实验为"灭非灵"的首次大型池塘实验,证明了"灭非灵"可以用于观赏鱼养殖中尼罗罗非鱼的特异性杀灭和控制,为以后观赏鱼行业中罗非鱼的清除提供了一种新的方法,同时也为外来鱼类的防控提供了新的思路。     

中国金鱼移植国外史浅探

金鱼起源于中国,现在已成为世界各国都喜爱的著名观赏鱼,探讨了金鱼被移养到世界主要国家和地区的时间和方式。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV