淡水鲳的鱼病防治

淡水鲳学名短盖巨脂鲤，原产于南美亚马逊河，是热带、亚热带的暖水性食用和观赏的大型鱼类之一。１９８２年引入我国台湾省，１９８８年获得了人工繁殖成功。由于淡水鲳生长迅速，受到各地的欢迎。随着淡水鲳养殖的推广，鱼病的发生也日益严重，危害较大。本文就淡水鲳的...     

淡水鲳越冬池应套养适量同规格尼罗罗非鱼鱼种

我县于1988年引进淡水鲳,在1990年利用塑料薄膜暖房进行淡水鲳越冬过程中,同时套养同规格尼罗罗非鱼鱼种,整个越冬期间基本上没发生鱼病,到1991年春出池,淡水鲳成活率达85.7％。而1989年     

淡水鲳的成鱼养殖技术

淡水鲳商品鱼的养殖,目前主要有四种方式:鱼种池套养、四大家鱼的成鱼池混养、池塘主养和集约化单养。本文介绍这四种方式的养殖技术,最后叙述养殖淡水鲳的实用饲料配方。一、鱼种池套养,育成商品鱼淡水鲳的苗种较少又缺乏养殖经验的生产单位,主要采用鱼种池套养的     

小山塘主养淡水鲳高产技术初探

小山塘主养淡水鲳高产技术初探陈启春（福建省淡水水产研究所，福州３５０００２）１９９４年在一口面积８．５亩的小山塘里，进行主养淡水鲳高产试验。收获时平均亩产达１０７７公斤，其中淡水鲳产量占总产量的６８．７％，亩产值８８１２元，亩效益２８５３元，取得令人...     

塑料薄膜暖房淡水鲳越冬技术

我县于1988年引进淡水鲳,经多年的养殖,我站初步摸索出淡水鲳越冬的方法,鱼种越冬成活率达到85%以上,亩均越冬产量9400多公斤。具体做法是:一、暖房的设计     

淡水鲳在我国繁殖成功

<正> 淡水鲳是我国近年引进的名贵养殖鱼类。在中国水产科学研究院长江水产研究所主持下,通过与广东省东莞市水产局协作,于1987年7月在我国首次人工繁殖淡水鲳成     

早繁淡水鲳当年养成技术

在１．８亩池塘中进行早繁淡水鲳当年养成技术试验，在无增氧机条件下，进行淡水鲳和罗非鱼混养。经１２８天饲养，平均亩净产５６０．９ｋｇ，其中淡水鲳为２８１．７ｋｇ，养在规格达５４０ｇ／尾，鉴定认为，当年养成这样的规格属省内领先水平。     

鲳亚目鱼类线粒体16S rRNA基因序列变异及其分子系统进化关系

为探讨鲳亚目鱼类的系统进化关系,通过测定中国沿海8种鲳亚目鱼类的线粒体16SrRNA基因部分序列,并结合GenBank上其他鲳亚目鱼类的同源序列,对其序列变异和分子系统进化树进行分析.结果表明,鲳亚目5科13属32种鱼类的16S rRNA基因序列的碱基组成为T 22.2％、C 24.5％、A 30.0％、G 23.3％;科间遗传距离为0.060～0.120,属间遗传距离为0.009 ～0.125,种间遗传距离为0.000 ～0.163;长鲳科位于系统进化树的基部,鲳科的鲳属处于系统进化树的顶端,无齿鲳科、方尾鲳科、双鳍鲳科与鲳科的低鳍鲳属和真鲳属聚类.结合形态学研究结果,认为:长鲳科是鲳亚目中最先分化的原始单系群;无齿鲳科和方尾鲳科为单系群,它们与非单系群的双鳍鲳科有较近的亲缘关系;鲳科为并系群,内部存在与地理区系相对应的2个分支,提示了该科鱼类早期的分化模式.同时,也对16S rRNA基因在鲳亚目鱼类系统进化研究中的适用性进行了剖析.     

淡水鲳的亲鱼培育和人工繁殖

前注:本刊第四期介绍了淡水鲳的生物学和池养特点,从本刊起将继续分期刊出淡水鲳的亲鱼培育和人工繁殖、苗种培育、成鱼养殖、越冬保种和防病技术。请各位读者注意收看并保存,或许能助你一臂之力。     

淡水鲳的越冬保种和鱼病防治技术

淡水鲳的下限临界温度为12℃。越冬水温低于24℃时淡水鲳很易生病,往往因此导致大批鱼死亡,造成越冬的失败。因此应该做好越冬保种工作,并注重其病害的防治。     

Growth performance of Colossoma macropomum(Cuvier) juveniles at different feed rations

Abstract Growth performance, feed utilization and changes in body composition of Colossoma macropomum (Cuvier) juveniles — in the weight range 2 to 200g — fed an artificial high protein diet, have been analysed against feed ration and fish weight. A polynomic equation is developed which permits prediction of growth and radon parameters in this weight range. The results are compared with the values of other cultured common freshwater fish species. Colossoma macropomum must be considered a very fast grower with good feed utilization.     

淡水鲳的催产与孵化

在浙江省北部地区的自然条件下,经过池塘培育和温流水越冬,淡水鲳是可以达到性成熟的,性成熟的年龄为3~ 龄,采用现行的四大家鱼催产剂,无论一次或分次注射,都能获得具有生命力的后代。     

The effects of trichlorfon, praziquantel and copper sulphate on various stages of the monogenean Benedeniella posterocolpa, a skin parasite of the cownose ray, Rhinoptera bonasus (Mitchill)

Abstract. Monogeneans of the superfamily Capsaloidea have been a severe problem in maintaining both teleosts and elasmobranchs in captivity. Infestations of Benedeniella posterocolpa on the skin of the cownose ray, Rhinoptera bonasus , provided an excellent model for testing the effects of trichlorfon (0-7ppm), praziquantel (20ppm) and copper sulphate (0-25 ppm) on adult monogeneans in situ , and on adult monogeneans, oncomiracidia and eggs in vitro. One treatment with praziquantel eliminated 100% of the worms from the skin of rays. Two treatments with trichlorfon only eliminated 81% of the worms. Praziquantel killed all worms tested in vitro within 6h and prevented egg deposition. Trichlorfon killed all worms within 21 h, but some eggs were deposited. Copper sulphate had little effect on worms in vitro. Both trichlorfon and praziquantcl immobilized oncomiracidia while copper sulphate had little effect. Eggs were relatively resistant to these chemicals; however, trichlorfon and praziquantel were the most effective in killing eggs.     

In vitro activity of chemicals and commercial products against Saprolegnia parasitica and Saprolegnia delica strains

Oomycetes of the genus Saprolegnia are responsible for severe economic losses in freshwater aquaculture. Following the ban of malachite green in food fish production, the demand for new treatments pushes towards the selection of more safe and environment‐friendly products. In the present work, in vitro activity of ten chemicals and three commercial products was tested on different strains of Saprolegnia, using malachite green as reference compound. The compounds were screened in agar and in water to assess the minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC), respectively. Two strains of Saprolegnia parasitica and one isolate of Saprolegnia delica were tested in triplicate per each concentration. Among tested chemicals, benzoic acid showed the lowest MIC (100 ppm) followed by acetic acid, iodoacetic acid and copper sulphate (250 ppm). Sodium percarbonate was not effective at any tested concentration. Among commercial products, Virkon^?S was effective in inhibiting the growth of the mycelium (MIC = MLC = 1,000 ppm). Actidrox® and Detarox® AP showed MIC = 5,000 and 1,000 ppm, respectively, while MLCs were 10‐fold lower than MICs, possibly due to a higher activity of these products in water. Similarly, a higher effectiveness in water was observed also for iodoacetic acid.     

池塘主养淡水白鲳高产试验

利用配合饲料在0.24hm~2池塘中主养淡水白鲳,经过140天养殖,平均每公顷净产鱼13802.0kg,其中淡水白鲳10103.0kg,平均体重为400.1g/尾,每公顷盈利124179.2元。投入产出比为1:2.0。     

Pharmacological level of copper induces the immune and antioxidant mechanisms of Fenneropenaeus indicus conferring better protection against white spot syndrome virus infection

Effect of ambient copper on the immune, antioxidant and lipid peroxidation parameters of Fenneropenaeus indicus and its susceptibility to white spot syndrome virus under heavy metal (Cu²⁺) exposure has been studied. Adult shrimps were acclimated to 25‰ salinity for a period of 7?days, and after 12?h of starvation, shrimps were dosed with 0.075, 0.150, 0.225 and 0.30?ppm Cu²⁺ by adding appropriate quantities of copper sulphate solution. After 14?days of metal exposure, the shrimps were challenged with white spot syndrome virus through oral administration and the immune and antioxidant parameters were analysed. Analysis of variance showed that there were significant differences (P?<?0.05) in the immune and antioxidant parameters and lipid peroxidation product in different treatment groups of F. indicus compared to untreated group. The immune parameters and antioxidant enzymes have been significantly lowered (P?<?0.05) in the haemolymph of shrimps dosed with higher concentrations of copper sulphate leading to lipid peroxidation and accumulation of malondialdehyde. However, there was less oxidative stress in shrimps exposed to 0.075?ppm Cu²⁺. The present study showed that high levels of Cu²⁺ enhanced the mortality of F. indicus with concomitant reduction in immune and antioxidant parameters. A concentration of 0.075?ppm Cu²⁺ in the rearing water was found to have beneficial effect in shrimps in terms of immunostimulation and higher survival against WSSV infection. This can be adopted as a pharmacological approach towards shrimp health management in culture systems.     

人工生态条件下鲥鱼保种越冬的试验研究

在低盐度人工生态条件下鲥鱼保种越冬获得成功。在总密度为56.13尾/米~2(鲥鱼0.37尾、淡水白鲳55.76尾/米~2)的条件下,鲥幼鱼成活率达92.0％,3龄鱼达100％;在鲥鱼密度为8.99尾、淡水白鲳密度为7.80尾/米。的条件下,鲥幼鱼成活率达89.4％,3龄鱼达100％。试验表明,鲥鱼越冬期间可摄食人工饲料,无需投喂浮游生物;鲥鱼的商品化养殖越冬是可行的。     

Menthol and 1,8‐cineole as new anaesthetics in common carp,Cyprinus carpio (Linnaeus, 1758)

This study describes anaesthetic efficacy of menthol and 1,8‐cineole in common carp, Cyprinus carpio, in comparison with eugenol. Common carp fingerlings were exposed to eugenol: 5, 10, 15, 25, 35, 50, 75, 100, 150 and 200 ppm; menthol: 5, 10, 15, 25, 50, 100, 200, 300, 400, 500 and 600 ppm; 1,8‐cineole: 100, 150, 200, 300, 400, 500, 600, 700 and 800 ppm. Induction time and recovery time were recorded. Results showed that menthol and 1,8‐cineole anesthetized the fish at higher concentrations compared to eugenol. The fish exposed to menthol showed common fish behavioural responses to anaesthesia, similar to eugenol. But, 1,8‐cineole‐exposed fish showed tail‐up swimming, which was not observed before. Also, 1,8‐cineole failed to completely cease muscle tone. Exposure to 200 ppm eugenol and 600 ppm menthol resulted in 40% and 20% mortality, respectively. Induction time was exponentially dependent on anesthetic concentrations. Recovery time was linearly correlated to eugenol and menthol, but not 1,8‐cineole concentrations. Recovery time was exponentially dependent on induction time in the fish anesthetized with eugenol and menthol, but not 1,8‐cineole. Menthol and 1,8‐cineole are recommended for carp anaesthesia. Menthol is capable to anesthetize common carp within 1–3 min at 118–512 ppm. Common carp anesthetized with 108–133 ppm menthol recovers within 5 min. 1,8‐cineole failed to anesthetize common carp within less than 150 s at 300–800 ppm concentrations. However, it anesthetizes carp within 3 min at 595 ppm concentration. Also, 1,8‐cineole is not recommended for fish surgery. Both menthol and 1,8‐cineole were less efficacious than eugenol.     

First record of infection by Trypanosoma sp. of Colossoma macropomum (Serrasalmidae), a neotropical fish cultivated in the Brazilian Amazon

Fish farming has grown rapidly in Brazil over the last two decades, due in part to the availability of water and species with potential for cultivation, such as Colossoma macropomum. This farmed fish, however, can be affected by parasitic infections with high mortality rates (>35%). The main objective of the present study was to describe the first occurrence of the Trypanosoma species in Colossoma macropomum, which occurred in fish cultured in the Brazilian Amazon region, as well as to morphologically characterize the trypomastigotes and the impact of these hemoparasites on the body condition of the hosts. The trypanosomes found in the blood of Colossoma macropomum were morphologically characterized by the size of the trypomastigote form, indicating the presence of only one morphotype. Of the 39 hosts examined from one fish farming, 41.0% were infected by Trypanosoma sp., with low levels of infection (mean blood density of 3.7/μL). The condition factor of the asymptomatic hosts was not affected by hemoparasitism. There was no correlation between the abundance of Trypanosoma sp. and the condition factor and size of the hosts. Finally, our understanding of host-parasite interactions and the detection of emerging diseases are fundamental for aquaculture.     

4种渔药对昆明裂腹鱼鱼苗的急性毒性试验

采用半静水式试验方法研究了在水温(16.5±0.5)℃、pH(7.70±0.25)条件下,高锰酸钾、三氯异氰尿酸、硫酸铜与硫酸亚铁合剂(5∶2)、敌百虫4种常用渔药对昆明裂腹鱼(Schizothorax grahami)鱼苗的急性毒性实验。结果显示:4种药物中三氯异氰尿酸的24 h、48 h、96 h半致死浓度最低,分别为1.586、1.423、1.173 mg/L,敌百虫的最高,为473、407、302 mg/L。4种药物的安全浓度分别为高锰酸钾0.536 mg/L,三氯异氰尿酸0.347 1 mg/L,硫酸铜与硫酸亚铁合剂(5∶2)0.5 mg/L,敌百虫90.41 mg/L。结果表明:4种药物中,三氯异氰尿酸、硫酸铜与硫酸亚铁合剂(5∶2)和敌百虫可在生产中安全使用。