Universal antisera for immunocytochemical identification of two different gonadotrophs in acanthopterygian fishes

Pituitaries of various teleosts belonging to 25 orders were immunostained with antisera raised against synthetic fragment peptides corresponding to conservative regions of gonadotropin subunits (mummichog FSH 50-60 and mummichog LH 91-106). Both immunoreactive FSH cells and immunoreactive LH cells were successfully identified in the fishes of almost every order of the superorder Acanthopterygii and several species of the superorders Paracanthopterygii and Polymixiomorpha, such as mullet, alfonsino, flyingfish, mackerel, flounder, cod, beardfish, etc. These antisera are therefore considered as universal antisera for immunocytochemical application to acanthopterygian fishes. Extensive diversity in the abundance of the FSH cells and the LH cells among species was noted even in fishes with similar gonadal stages, indicating the possibility that the respective roles of FSH and LH may vary considerably among species in advanced teleosts.Evident but generally weak immunoreactivities to anti-mummichog LH 91-106 were observed in the fishes of the superorder Cyclosquamata; and slight or weak immunoreactivities to the antiserum were observed in the fishes of several more primitive taxa (superorder Stenopterygii, Protacanthopterygii, Ostariophysi, subdivision Clupeomorpha, and subdivision Elopomorpha). No immunoreactivity to anti-mummichog FSH 50-60 was observed in these fishes. These results are consistent with the phylogenetic status of the fishes and the degree of conservativeness in the amino acid sequences of the antigen regions.     

日本鳗鲡仔鱼摄食机理及其营养策略

鳗鲡属(Ａｎｇｕｉｌｌａ)鱼类共有19种和亚种,其中以欧洲鳗鲡(Ａ.ａｎｇｕｉｌｌａ)和日本鳗鲡(Ａ.ｊａｐｏｎｉｃａ)最为重要。鳗鲡属鱼类发育需经历奇特的柳叶状仔鱼(ｌｅｐｔｏｃｅｐｈａｌｕｓｌａｒｖａ)阶段,其人工育苗技术是一道世界难题。柳叶状仔鱼现象仅见于真骨鱼类最原始的一个类群海鲢总目Ｅｌｏｐｏｍｏｒｐｈａ(鳗鲡目Ａｎｇｕｉｌｌｉｆｏｒｍｅｓ,海鲢目Ｅｌｏｐｉｆｏｒｍｅｓ,背棘鱼目Ｎｏｔａｃａｎｔｈｉｆｏｒｍｅｓ)。有关柳叶状仔鱼的发育策略,已从形态学、生理学及生物化学等方面进行了不少研究,但柳叶状仔鱼…     

Genetics of neotropical fish: from chromosomes to populations

The Neotropical freshwater fish fauna is very rich—according to the most recent catalogue 71 families and 4,475 species have been described. However, only a small amount of general information is available on the composition of Neotropical marine fishes. In Brazil, 1,298 marine species have been recorded. General analysis of available cytogenetic and population genetic data clearly indicates research has been mainly concentrated on freshwater fishes. Thus, today, cytogenetic information is available for 475 species of Characiformes, 318 species of Siluriformes, 48 species of Gymnotiformes, 199 freshwater species that do not belong to the superorder Ostariophysi, and only 109 species of marine fishes. For the species studied, only about 6% have sex chromosomes and about 5% have supernumerary or B chromosomes. A review of the cytogenetic studies shows that these data have provided valuable information about the relationships between fish groups, the occurrence of cryptic species and species complexes, the mechanism of sex determination and sex chromosome evolution, the distribution of nucleolus organizer regions, the existence supernumerary chromosomes, and the relationship between polyploidy and evolution. In relation to populations in Neotropical marine waters, the studies have shown the presence of cryptic species, which has important implications for fishery management. Different levels of genetic structuring can be found among Neotropical freshwater migratory fish species. This raises important implications for fish population genetic diversity and consequently its sustainable utilization in inland fisheries and aquaculture, specifically for conservation of ichthyo-diversity and survival.     

北盘江光照水电站建设前后鱼类资源变化

2009年9月和2010年5月,对北盘江光照水电站影响河段鱼类资源进行现场调查,采集鱼类45种,其中18种为新记录种,各河段鱼类组成特点与生态类型相符。结合相关文献资料,确定调查河段鱼类共71种,其中珍稀濒危鱼类4种,珠江水系特有鱼类3种。光照电站的建设对库区河段的鱼类资源影响显著,喜静缓流生境鱼类占76.5%,喜急流或流水生境鱼类占23.5%;流水生境河段受影响较小,约90%鱼类喜流水生境。调查水域没有典型产漂流性卵鱼类的产卵生境,原记录的产粘性卵鱼类产卵场受影响较小。     

中国海洋鱼类种类多样性的研究

中国海洋迄今已记录有３０４８种鱼类，分属２８８个科，约占全球海洋鱼类总数的２３％，是世界鱼类种类最丰富的国家之一。种类多样性程度由南向北逐渐递减，南海高达２０５０种，但单种资源量小，黄渤海只有３２７种，但一些单种资源量较多，中国海洋针种以暖水种居多样性的高达８７．８％，也有大量暖温种和少数冷温种，但无真正冰水各，中国海缺乏世界级的高产渔获种类。     

松花江鱼体内汞的残留水平

1990－19991年,对松花江鱼体内汞含量进行了测定和分析。结果表明,各种鱼类肌肉中汞含量的顺序为：底层鱼＞上层鱼;肉食性鱼＞杂食性鱼＞草食性鱼。此外,分析比较了东北地区不同水体鱼体汞含量情况;显示松花江鱼体内汞的含量比其它水体鱼体含汞量高。     

北盘江光照水电站建设前后鱼类资源变化

2009年9月和2010年5月,对北盘江光照水电站影响河段鱼类资源进行现场调查,采集鱼类45种,其中18种为新记录种,各河段鱼类组成特点与生态类型相符。结合相关文献资料,确定调查河段鱼类共71种,其中珍稀濒危鱼类4种,珠江水系特有鱼类3种。光照电站的建设对库区河段的鱼类资源影响显著,喜静缓流生境鱼类占76.5%,喜急流...     

Persistence of native fishes in small streams of the urbanized San Francisco Estuary,California: acknowledging the role of urban streams in native fish conservation

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鱼类热忍耐温度研究进展

The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect: (1) The key parameters of temperature of thermal tolerance in fishes; (2) The influence factors of temperature of thermal tolerance in fishes; (3) The research methods of thermal effect of fishes; (4) The evaluation of effects of thermal pollution on fishes, especially, with the coastal power station will be‘built in China recent years, the effects of thermal discharge water on the marine fisheries resource wered iscussed.     

Diet and trophic niche overlap of native and nonnative fishes in the Gila River,USA: implications for native fish conservation

Pilger TJ, Gido KB, Propst DL. Diet and trophic niche overlap of native and nonnative fishes in the Gila River, USA: implications for native fish conservation. Ecology of Freshwater Fish 2010: 19: 300–321. © 2010 John Wiley & Sons A/S Abstract –  The upper Gila River basin is one of the few unimpounded drainage basins west of the Continental Divide, and as such is a stronghold for endemic fishes in the region. Nevertheless, multiple nonindigenous fishes potentially threaten the persistence of native fishes, and little is known of the trophic ecology of either native or nonnative fishes in this system. Gut contents and stable isotopes (¹³C and ¹⁵N) were used to identify trophic relationships, trophic niche overlap and evaluate potential interactions among native and nonnative fishes. Both native and nonnative fishes fed across multiple trophic levels. In general, adult native suckers had lower ¹⁵N signatures and consumed more algae and detritus than smaller native fish, including juvenile suckers. Adult nonnative smallmouth bass (Micropterus dolomieu), yellow bullhead (Ameiurus natalis) and two species of trout preyed on small‐bodied fishes and predaceous aquatic invertebrates leading to significantly higher trophic positions than small and large‐bodied native fishes. Thus, the presence of these nonnative fishes extended community food‐chain lengths by foraging at higher trophic levels. Although predation on juvenile native fishes might threaten persistence of native fishes, the high degree of omnivory suggests that impacts of nonnative predators may be lessened and dependent on environmental variability.     

Carbon source and trophic position of pelagic fish in coastal waters of south-eastern Izu Peninsula,Japan, identified by stable isotope analysis

ABSTRACT:   It is important to clarify trophic dynamics in marine ecosystems for management of the fishing ground. Organic carbon sources and trophic position of pelagic fishes in the coastal waters of the south-eastern Izu Peninsula, Japan, were examined on the basis of carbon and nitrogen stable isotope distributions. The δ¹³C of the fishes was mostly distributed from −19 to −16‰ for nektonic fishes (13 species of adults and immatures) and planktonic fishes (10 species of larvae and juveniles), close to the δ¹³C values of particulate organic matter and planktonic decapods. These δ¹³C signatures for the inhabitants of the water column were in contrast with the high δ¹³C values (mainly −16 to −13‰) for demersal fishes of Scorpaeniformes and benthic polychaetes collected in the surf zone. These results indicate that nektonic and planktonic fishes depend on phytoplankton for carbon supply. The δ¹⁵N signatures suggest that the trophic position ranged 3.1–4.5 for the nektonic fishes and 2.9–3.7 for the planktonic fishes, premised on trophic level 3 for larval Japanese anchovy Engraulis japonicus . Thus, planktivorous fishes should be mainly assigned to trophic levels 3 and 4 in this area.     

莱州湾水域鱼类生物完整性评价

采用莱州湾水域鱼类生物完整性指数评价生态系统健康状况,为该水域的生态修复和渔业资源的可持续管理提供科学依据。2016-2017年在莱州湾采用底拖网开展鱼类资源调查,共捕获鱼类52种。参照1982-1983年的历史资料确定评价标准,从鱼类种类组成与丰度、繁殖共位群和营养结构等角度,筛选适用于莱州湾水域鱼类生物完整性(Fish index of biological integrity,F-IBI)评价的指标体系,得到鱼类总种类数、冷温性鱼类比例、中上层鱼类种类数比例、平均单位网次渔获量、多样性指数、产浮性卵鱼类比例、产粘着性卵鱼类比例、低耐污鱼类种数比例、广食性鱼类比例、底栖动物食性鱼类比例、浮游动物食性鱼类比例和杂食性鱼类比例等12个参数指标。根据评价指标体系计算F-IBI,结果显示:莱州湾水域的F-IBI得分为30,其完整性等级为“差”,表明莱州湾水域生态健康状况差。建议采取面源污染控制和基于生态系统保护的渔业管理恢复莱州湾水域生态系统健康。     

黑龙江流域鱼类资源现状及放流鱼类选择

详细阐述、分析了黑龙江流域鱼类的资源现状及濒危状况、黑龙江流域鱼类放流现状及效果、增殖放流物种选择依据等,提出拟选择施氏鲟、达氏鳇、大麻哈鱼、驼背大麻哈鱼等11种鱼类为黑龙江水域第一批增殖放流鱼类,探讨了拟选择鱼类生态特点.最后根据黑龙江流域鱼类放流现状,提出了需要研究的问题.     

绥芬河鱼类区系组成研究

绥芬河是我国注入北太平洋日本海的第二条水系。由于该水系地处寒温带,气候、地理环境和生态条件特殊,因而蕴藏着丰富的冷水性鱼类、溯河性洄游鱼类种质资源,仅大麻哈鱼类就有3种,每年5～10月回归溯河洄游:鲤科溯河性洄游鱼类有三块鱼、珠星三块鱼等,呈现出北太平洋日本海水系鱼类区系的特色,成为我国名贵珍稀经济鱼类地理分布的重要水域。在鱼类区系组成上,它与相邻的水域有着很大的差异,在我国北方水域鱼类演替和区系划分上有着重要的意义。关于绥芬河鱼类区系,国内外学者都进行过研究。笔者在2005～2006年采集了大量的鱼类标本,整理和增补了10种鱼类,对绥芬河鱼类区系作了初步的概述,为我国北方水域鱼类演替、区系区划研究、开发利用及资源保护提供了科学的依据。     

家用型水族箱养殖海水观赏鱼技术

海水观赏鱼以其怪异的体型、鲜艳的色彩,深受观赏鱼爱好者的青昧。家庭及办公场所海水观赏鱼饲养者常因养殖技术缺乏、经验不足而导致饲养失败。笔者结合自身养殖经验对水族箱的设置、观赏鱼品种的选择、水质指标的控制、饵料投喂及病害防治方面进行了分析与探讨,为家用型水族箱饲养海水观赏鱼提供技术支持。     

防城港人工礁区内5种恋礁鱼类的声学标志跟踪

为了解人工鱼礁区鱼类的活动特点及使用超声波遥测方法进行人工鱼礁区鱼类研究的可行性, 2017年7月7日至9月8日于防城港人工鱼礁区利用Vemco定位系统(Vemco position system, VPS)对5种北部湾沿海常见的野生恋礁性鱼类共9尾[体长(21.7±3.8) cm,体重(314±186) g]进行超声波标志遥测跟踪。结果表明, 9尾鱼中的3尾定位效果较为理想(1749～9591个定位结果),活动范围较小,其中100%最小凸多边形(minimum convex polygon, MCPs)范围为12687.6～17123.2 m^2。而50%和95%核心利用分布(Kernelutilizationdistribution,KUDs)范围为5788.1～8708.9 m^2和10240.5～16463.7 m^2。另6尾鱼未取得理想的定位效果(0～14个定位结果),接收机接收回的定位数据可以被检测,表明鱼依然在礁区附近活动。在游离检测范围28～51 d后又有信号返回,说明样本鱼对人工鱼礁环境有一定的偏好性,研究期间样本鱼表现出一定的活动深度变化规律,在15:00～22:00时段活动深度相对较浅,主要集中于人工鱼礁礁体上方(距水底5 m以上)。研究表明,应用超声波遥测技术可以了解鱼类在自然生活状态下的活动特点,可作为鱼类研究的有效手段加以应用。     

Taxonomic and geographic gaps in understanding the functional effects of imperilled fishes on freshwater ecosystems

The effects that fishes have on rates of one or more ecosystem processes (hereafter referred to as functional effects) are often invoked as an important reason for imperilled species conservation. However, the degree to which we understand these effects is rarely evaluated for most groups of fishes. We assessed how well the functional effects of freshwater and diadromous fishes, one of the most imperilled groups of animals, are quantified to date. We found that 88% of studies considering the functional effects of imperilled North American fishes were conducted on one family, Salmonidae. Studies of the functional effects of fishes were also concentrated in Pacific drainages of North America, with few studies in hotspots of imperilled fish diversity such as the Southeastern United States, the arid Southwest and central Mexico. Our results demonstrate the vast taxonomic and geographic gaps in our functional understanding of imperilled fishes and highlight the need to broaden this work to justify the argument that they are functionally important in the ecosystems they inhabit.     

基因工程技术在我国淡水鱼类育种上的应用

近20年来，随着转基因工程技术的兴起和应用，我国在淡水鱼类的抗病育种上取得了可喜的研究成果，为进一步用转基因工程技术培育优良鱼种奠定了良好的学术基础。     

Method for underwater measurement of the auditory brainstem response of fish

ABSTRACT:   The auditory brainstem response (ABR) of fishes is commonly measured by bringing the heads of the fishes out of the water in a small tank. However, this method is inapplicable to experiments for large fishes that are economically important in large spaces such as the sea or in a large tank. This paper describes a method of recording, the ABR for fishes in water, without exposing the fish heads to air, by using a waterproof, insulated electrode. To evaluate the effectiveness of this method, the goldfish Carassius auratus was investigated, and the ABR waveform and auditory thresholds measured in water were compared with those measured on the surface. Both ABR waveforms and auditory thresholds showed similar trends between the two methods. The underwater ABR method is useful to measure the auditory thresholds of larger fish in natural or on-site environments such as the sea, net enclosures and large aquaria in which precise positioning of the fish is not possible. However, more improvement is needed to apply this method to large fishes.