七彩神仙鱼繁育技术要点

七彩神仙鱼以其独特而神秘的美感、娇嫩而敏感的体质而被誉为热带观赏鱼之后,是最受喜爱的热带观赏鱼之一。尽管它的养殖技术早已普及,繁殖也已不是什么难事,但以生产大量商品鱼为目的的苗种繁育仍有很多值得探讨的地方。笔者根据自己的实践经验以及对一些专业渔场的学习考察,整理出了以下技术要点,供养殖者参考。     

七彩神仙鱼的繁养殖技术

七彩神仙隶属于鲈形目、丽鱼科、盘丽鱼属，原产于亚马逊河流域的热带雨林中。它以其艳丽的色彩、优雅的姿态吸引了众多的观赏鱼爱好者，在世界各国被视为热带鱼的极品，在我国七彩热仍长盛不衰。本文对七彩神仙鱼的繁养殖技术提出一些见解，旨在对七彩神仙鱼的养殖工作者和爱好者提供参考的资料。     

七彩神仙鱼生产技术（下）

4.孵化阶段此阶段的管理包含两方面的内容:一是照料受精卵和小鱼苗,另一方面还要照料亲鱼。(1)初产卵可以加铁丝罩网保护后由其在产卵缸内孵化,由于受精率肯定不高,不必太多的照料。到亲鱼产第3批卵时,一般受精率已经比较高了,孵化要认真对待。有两种孵化方式可供选择:一种是上     

七彩神仙鱼的家养技术要点（上）

七彩神仙鱼又名七彩燕鱼、盘丽鱼,见题图(从左至右分别为:豹点红点绿七彩、霓虹蓝、状元红、火焰绿皇帝七彩、小丑蓝点红七彩、蓝底火焰红七彩),属热带鱼中的慈鲷鱼科,原产于南美洲的亚马逊河流域。鱼体大小中等,侧扁,尾鳍扇形,形如满月,色彩丰富艳丽,性情稳重,游姿优雅,雍容华丽,素有“热带观赏鱼之王”的美称。     

七彩神仙鱼工厂化养殖技术初探

为探究七彩神仙鱼工厂化养殖技术,在水温28～30℃的室内水泥池中开展了七彩神仙鱼养殖试验,放养的幼鱼全长1.5～2.0 cm,放养密度为200尾/m³。经过约120 d养殖,试验鱼全长达9.0～10.0 cm,达到商品规格。结果表明,七彩神仙鱼每年可养殖3茬,平均成活率达87.8%,平均单位水体产出达175.6尾/m³。工厂化养殖系统可全年生产运转,水质相对稳定,单位水体养殖密度较高。     

七彩神仙鱼的人工养殖技术

七彩神仙原产于亚马逊河的贝雷(Belem)河口到上游的伊基特斯之间的广大流域，因其美丽的姿色而倾倒广大鱼迷朋友。它具有极高的观赏价值，是热带鱼中的极品，因此，它的人工养殖技术更是为人们所迫切掌握的。笔者愿就几年来对七彩神仙的养殖经验与广大鱼迷交流。     

七彩神仙鱼的家养技术要点（下）

三、饲养鱼的放养 1.放养密度:一只0.6米×0.4米×0.5米的玻璃鱼缸或体积大小约为80升左右的其它形状的鱼缸可放养3～4厘米长的幼鱼20～30尾。或通过计算得出宜放养的鱼数,计算公式为:饲养缸可养鱼数(尾)=饲养缸体积(升)÷鱼的体长(厘米)。     

都市流行七彩神仙

观赏鱼,这一专业名词在十多年前的百姓口中并不常提及。同样,除金鱼外,知道观赏鱼中还有锦鲤、热带鱼的也不多,至于来自亚马逊河流域的七彩神仙鱼则知之者更少。但是,如今只要你稍加留心便可发现,从国外到国内,从我国南方到北方,从花鸟鱼虫市场到观赏鱼爱好     

七彩神仙鱼的集约化高效养殖技术

七彩神仙(Symphysodonaequifasciata)是广受欢迎的观赏鱼之一。原产地为南美洲的亚马逊河热带雨林流域。该鱼对养殖条件与养殖技术要求苛刻,稍有不慎,就难获得成功。我们从1999年起,在80m2的平房内,利用水族箱进行七彩神仙鱼的集约化养殖技术研究。经过3年的摸索,2002年自繁自养共培育出七彩神仙鱼2万余尾,获纯利19万余元,取得了较好的经济效益。现总结于下,供同行们参考。一、材料与方法1、养殖基本条件(1)养殖场地养殖场地为一间80m2的平房。由繁殖区和育成区两部分组成,繁殖区占地20m2,安放有自制玻璃水族箱共计30个,其中规格为50cm×50…     

Characterization of protease activity in developing discus Symphysodon aequifasciata larva

The activity of different protease classes was monitored in developing discus (Symphysodon spp.) larvae using a combination of biochemical assays and substrate SDS–PAGE techniques. Results showed the presence of alkaline proteases of serine proteases such as trypsin with a significant increase in activity levels detected beginning 3 days after hatching. Other alkaline proteases such as metallo‐proteases and chymotrypsin, a type of serine protease, were only detected in older larval stages, at around 20–30 days after hatching. Acidic protease activity was very low during the first 20–25 days of development before showing a significant (P < 0.01) rise. This is despite the formation of a stomach observed 10 days after hatching. Based on the development of the protein digestive system observed, the use of microdiets to replace Artemia should be considered 25 days after hatching.     

水硬度对七彩神仙鱼幼鱼发育的影响

采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。     

Amino Acid Profile of Various Body Tissues and Eggs of Discus Fish,Symphysodon aequifasciata

Abstract

Amino acid profiles of various body tissues from juvenile and adult discus fish, Symphysodon aequifasciata, were compared. Results from whole-body tissue revealed significant difference (P < 0.05) between the levels of lysine, phenylalanine, alanine, aspartic acid, and serine among the two different fish sizes. Levels of arginine, histidine, leucine, methionine, phenylalanine, and threonine were also higher in muscle tissue of adult fishes. Analysis of gill tissues showed significant difference in levels of histidine, isoleucine, lysine, methionine, threonine, tryptophan, aspartic acid, glutamic acid, proline, and serine were significantly different among the different fish stages. This study also showed that among all ten essential amino acids, muscle had the highest levels of histidine, isoleucine, lysine, and tryptophan; gills had the highest level of arginine; while levels of methionine and threonine were higher in the intestinal tissue. Regression analysis between the calculated whole-body A/E ratio of discus juveniles and with quantitative dietary amino acid requirements of several fish species also showed significant correlation, with highest r values (> 0.90) obtained with tilapia, common carp, channel catfish, and Japanese eel. This profile may be useful as a preliminary reference index to evaluate suitability of various ingredients in terms of amino acid profile for development of economical diet for discus farming.     

饲料中脂肪含量对七彩神仙鱼幼鱼生长和消化的影响

在水温29.0±1.0℃下,将140日龄、体质量8～10g的七彩神仙鱼(Symphysodon aequifasciata)幼鱼放入室内54cm×40cm×28era的水箱中,投喂以鱼粉和豆粕为蛋白源(粗蛋白45.0%)、以豆油为脂肪源配制的5种脂肪水平(10.21%、12.02%、17.17%、21.0%,和22.14%)的饲料.90d的饲养表明,七彩神仙幼鱼的成活率变化在96.67%～100.0%之间,各组间差异不显著(P>0.05).随饲料中脂肪含量的增加,鱼的特定生长率(SGR)、蛋白质效率(PER)和增重率均先增加而后降低;摄食含12.02%脂肪饲料的鱼SGR、PER和增重率极显著地高于摄食含10.22%和22.14%脂肪饲料的鱼(P<0.001),而当鱼摄食含17.17%和21.05%脂肪的饲料时,SGR、PER和增重率与摄食含12.02%脂肪饲料的鱼差异不显著(P>0.05).当饲料中脂肪含量为12.02%时,鱼对饲料中蛋白质的消化率最高;摄食含脂肪为10.22%、12.02%和17.17%的饲料时,对饲料蛋白的消化率差异不显著(P>0.05).实验表明,七彩神仙鱼幼鱼饲料中适宜脂肪含量在12.02%～17.17%之间.     

Assessment of soybean meal in diets for discus (Symphysodon aequifasciata HECKEL) farming through a fishmeal replacement study

A 12‐week feeding trial was carried out with discus (Symphysodon aequifasciata HECKEL), a valuable ornamental species produced in South East Asia, to determine the suitability of using soybean meal as a partial fishmeal substitution in the diet. Juvenile discus (4.3–4.8 g) was fed eight experimental diets with graded levels of soybean meal replacing fish meal (0%, 10%, 20%, 25%, 30%, 35%, 40%, 50%). Growth performance (relative growth rate, specific growth rate) decreased and feed utilization (feed conversion ratio, protein efficiency ratio) was worsened at 30% replacement and higher. Amino‐acid analysis indicated methionine and lysine deficiencies at dietary high soybean replacement levels, although the essential amino‐acid requirements for this species are unknown. The level of soybean in diets negatively affected both dry matter and protein digestibility. This present trial showed the need for further studies involving amino‐acid supplementation, different soy products and palatability enhancement to improve utilization of diets containing soybean meal to allow higher than the maximum 30% replacement level suggested here.     

工业化养鱼的进展

概述了国内外工业化养鱼的现状：指出该项产业科技含量大，是新兴的知识型产业，开展工业化养鱼有利于对渔业资源的保护及对水域环境的治理；通过对我国工业化养鱼简短的历史回顾，分析讨论了发展中的制约因素，以及今后的工作方向。     

Intensive Culture Potential of Penaeus vannamei

Tank and pond rearing studies were conducted to assess the potential for intensive culture of Penaeus vannamei in South Carolina. Postlarvae were stocked in intensive nursery tanks at 500/ m². Growth and survival were compared for shrimp reared in control fiberglass tanks and in tanks with artificial substrates (fiberglass screen). Addition of substrate improved survival (82% versus 58%), but not growth. Juvenile shrimp (mean weight, 1.3 g) from the nursery trial were stocked into 6 m diameter tanks at densities of 10, 20 and 40/m². Growth rate was inversely related to stocking density, with mean sizes of 33.9, 32.5, and 26.7 g attained at the low, medium, and high densities respectively after 168 days. At harvest, standing crop biomass averaged 225.6, 442.0, and 685.4 g/m² for the three densities. To further test the intensive culture potential, two 0.1 ha ponds were stocked with hatchery-reared postlarvae at densities of approximately 40 and 45/m². The ponds were managed intensively using paddlewheel aerators and water exchange averaging 16–17%/day. The ponds were harvested after 138 and 169 days and yielded 6,010 kg/ha of 16.7 g (mean weight) shrimp and 7,503 kg/ha of 17.9 g shrimp, respectively. Average production was 6,757 kg/ha with a food conversion of 2.51. These data suggest good potential for intensive pond culture of P. vannamei in South Carolina and other areas of the continental United States.     

青虾人工集约高产养殖初探

随着人民生活水平的提高,传统养殖品种市场行情一直走低,养殖效益日益下滑,调整养殖品种结构已迫在眉睫,为此,我们对青虾人工集约化高产养殖进行了一些探索。1鱼池条件养殖池位于五岳水库渔场,标准化鱼池6个,单池面积5亩,计30亩;形状为长方形,系东西走向;长宽比为2.5∶1;水源引自五岳水库,自流排灌,水质清新,溶氧丰富;进水口和排水口分设在虾池两端,设有过滤和防逃设备。2放养前的准备工作放养前15天,池塘经过干池暴晒和生石灰干法清塘(每亩施生石灰85kg),进水时用80目尼龙筛绢网过滤,加水1.0m左右。在鱼池中设置用旧网片、树枝和凤眼莲为青…