堵住漏洞整治卤虫市场

编辑同志: 目前由于鱼虾育苗生产中需要使用大量的卤虫卵,致使卤虫卵供不应求,价格暴涨。一些经营卤虫卵的单位和个人,便想出了极为“巧妙”的办法——收集育苗场随意丢弃的卤虫卵壳,或者以象征性的价格收集卤虫卵壳,然后再把卤虫卵壳与卤虫卵掺杂在一起,以次充好,再次出售,从中牟取暴利。这种做     

糠虾作为河蟹人工育苗饵料的应用

<正> 在河蟹育苗过程中,溞V变态为大眼幼体及大眼幼体至出池阶段的管理是整个育苗工作的关键。这一阶段营养最为重要,以往主要使用卤虫幼体和成虫。但是,由于蟹苗价格不断下滑,卤籽和卤虫价格不断飞涨,严重影响了河蟹育苗的经济效益。对此,我们改用糠虾作为这一阶段的主要饵料,通过生产性试验,取得了较好的效果,现将试验过程报告如下:     

生产性加工及采集贻贝（Mytilus edulis L．）卵的方法

在对虾工厂化育苗中，饵料培养，特别是动物性饵料轮虫的生产性培养，目前尚有一定的困难。一般来说，因为需要一定规模的培养设备和条件，同时，尚需一定的培养方法与技术。因此，目前大部分生产单位在对虾人工育苗中所使用的活体动物性饵料主要以卤虫(Artemia salina)无节幼体为主，     

提高卤虫休眠卵孵化率的技术因子探讨

卤虫休眠卵的孵化是目前海水鱼虾育苗工作中的活饵料供应体系，本文结合上海地区低盐度海水对虾育苗工作，经多年实验观察，归纳总结提高卤虫休眠卵孵化率的主要技术措施，其中包括孵化设备装置、水质控制、加快脱壳处理、以及鉴别卵的质量标志等     

卤虫的利用及其休眠卵质量优劣的鉴别

自从将卤虫无节幼体用于鱼虾育苗后，育苗工作取得突破性进展。之后随着对卤虫基础理论及应用的深入研究，卤虫的利用更加广泛。目前，国际上85％的海产经济动物以卤虫作为其主要开口饵料之一。另外，在环境监测，产盐业及基础生物等方面的研究和应用也相当普遍，据不完全统计现全世界的每年有100多万吨的卤虫卵交易，但随着卤虫的广泛利用，在水产养殖业中出现了一系列问题。最近十几年海珍品养殖发展很快，世界市场亦逐年扩大，海珍品的发展要求更多的优质的饵料，因此卤虫的价格也应相应提高。一、卤虫在水产养殖业中的利用及问题卤虫在…     

不同海水消毒方法在扁藻培养中培养效果的比较

<正>单胞藻是贝类、虾蟹类等水产经济动物的天然饵料,同时也是轮虫和卤虫的天然饵料,在育苗生产中占有极其重要的地位,尤其贝类苗种培育,直接关系到育苗的成败。目前,由于育苗厂家的不同及单胞藻培养规模的不同,选择的培养用水的消毒方式也有所不同,但对规模较大的水体的消毒以氯制剂为主,如漂白粉、漂白液、二氯异氰脲酸钠、三氯异氰脲酸及被人推崇为第四代消毒剂的二氧化氯。不同的含氯消     

加快我国卤虫资源开发论证会在北京召开

据前不久在北京召开的“关于加快我国卤虫资源开发的意见”论证会透露:“九五”期间,我国将加大卤虫资源的开发力度,国产卤虫的应用要逐步替代进口,出口数量将逐年增加,到2000年,全国水产育苗用卤虫全部国产化。 卤虫卵是虾蟹幼体的优良饵料,随着水产养殖业的发展,需求量明显攀升,缺口越来越大。美国、巴西、俄罗斯等一些生产国市场前景看好,而美国作为我国主要卤虫卵供应国由于近年来丰歉不定,价格上     

搞好卤虫资源保护和合理开发

卤虫幼虫是鱼虾蟹幼体的最佳饵料,有很高的经济价值。近几年,由于虾蟹育苗生产的迅速发展,沿海卤虫卵供不应求,价格暴涨。河北省张家口地区畜牧水产局,为开发利用当地卤虫资源,在今年初专     

对虾仔虾期的代用饵料——糠虾

随着对虾苗种生产的发展,对动物性饵料——卤虫无节幼体的需要量也随之增加。主要产于河北、辽宁二省的卤虫冬卵供不应求。为解决卤虫无节幼体供应不足的问题,1986年我们在启东县海水养殖场对虾人工育苗中,试用新鲜糠虾代替卤虫无节幼体喂仔虾,取得了可喜的结果。该场共有对虾育苗池     

卤虫卵品质与育苗成活率

由于条件所限，苗场对卤虫卵的质量鉴定往往只测定孵化率，依据孵化率的高低来判断卤虫卵的好坏，并且决定是否采用。实践证明，光测孵化率还不能证明卤虫卵的好坏，孵化率仅仅是一个方面。因为笔者就遇到过一种卤虫卵孵化率高达 90％，虾苗却 90％以上都死亡的情况。关于这一点，笔者曾与多位育苗同行讨论过，同行也深有感触，只是苦于没有有效的手段来鉴别卤虫卵的品质。 　　虾、蟹育苗都要用到卤虫无节幼体，虾、蟹苗 (幼体 )的营养完全依靠卤虫无节幼体，若卤虫无节幼体营养缺乏，必然影响到虾、蟹育苗的成活率。罗氏沼虾育苗死亡高峰…     

Effect of disinfectants on the hatching of marine rotifer resting eggs Brachionus plicatilis Müller

Scanning electron microscopy indicated that stored resting eggs of the marine rotifer Brachionus plicatilis Müller were colonized by numerous bacterial cells that affect the hatchability of resting eggs. The effectiveness of chemical disinfectants on the hatching of the resting eggs was studied using selected chemicals and antibacterial drags. The hatching success rate of the fresh and stored eggs was 26 ± 5.8% and 0%, respectively. Sodium hypochlorite (1.0 p.p.m.) increased the hatching rate to 48 ± 1.3% in freshly-collected and 28 ± 1.8% in stored eggs. Physical disintegration of the bacterial mat occurred after 1 h of treatment with sodium hypochlorite. Among antibacterial drugs, sodium nifurstyrenate (Erubaju) enhanced the hatching success rate to 40 ± 1.2% and 20 ± 1.1% for the freshly-collected eggs and stored resting eggs, respectively. However, tetracycline and oxytetracycline did not significantly influence the hatching of the stored eggs. These observations are discussed in relation to the development of an improved method for the processing and hatching of rotifer resting eggs.     

基于循环水孵化系统的俄罗斯鲟受精卵孵化性能研究

目前,绝大多数海淡水增养殖鱼类的苗种繁育几乎完全是人工繁殖,但对受精卵的孵化方式的研究较少,尤其循环水孵化方面。为探索封闭循环水孵化系统对鲟鱼(Acipenseriformes)受精卵孵化性能的影响,本文通过对俄罗斯鲟(Acipenser gueldenstaedtii)受精卵孵化率、孵化酶组成和含量以及孵化过程中水体氨氮浓度变化规律进行研究。结果显示,封闭循环水孵化系统中总氨氮浓度随孵化时间呈线性增长,受精卵的排氨率为60~90 mg/(g·h),破膜6 h后孵化率为86%,孵化水体中孵化酶累积较严重。俄罗斯鲟的孵化酶主要由分子量为41.3 k Da的蛋白质组成,受精卵的孵化液由23种蛋白质组成,其中包括7种水解酶。研究表明,对氨氮的去除及孵化酶控制技术是循化水孵化系统急需攻克的首要问题。     

The effect of temperature and duration of incubation on the hatching of diapause eggs of Centropages hamatus (Lilljeborg) (Copepoda, Calanoida)

Diapause eggs of Centropages hamatus were used to investigate the effect of temperature and duration of incubation on egg hatching. Eggs were incubated for 10, 12, 14, 16, 20, 24, 28, 32, 36 and 40 h at 15°C and 14L–10D. After incubation for the designated period, eggs were transferred to 25°C and monitored periodically to determine egg hatching. Control eggs were incubated solely at 15°C and monitored for egg hatching. The greatest daily hatching success of eggs occurred within 1 or 2 days after transfer from 15°C to 25°C, while the controls required 3–4 days. The cumulative hatching success of eggs was significantly lower than the control, with the exception of eggs held for at least 36 h at 15°C before transfer to 25°C. These results indicate that overall time to hatching of diapause eggs of C. hamatus can be reduced by transferring the eggs to a higher temperature, for example, 25°C, following a minimum period of time (36 h) at reduced temperature, for example, 15°C. Exposure to 15°C for only 10 h does not appear to be sufficient to result in any subsequent hatching at higher temperature.     

Improving cold storage of subitaneous eggs of the copepod Acartia tonsa Dana from the Gulf of Mexico (Florida – USA)

Developing methods to store copepod eggs is necessary to increase the availability of copepods as a live food for the aquaculture industry and aquarium trade, and also to allow the exchange of copepods between researchers. The present study, evaluated the effect of glucose and two antibiotics (kanamycin sulphate and oxytetracycline HCl) on extending the shelf life of cold-stored subitaneous Acartia tonsa eggs. Also, egg development effects on the survival of the eggs were tested. Glucose did not have any significant effects on the survival of the eggs. However, the addition of antibiotics to the storage vials resulted in an increase of the survival of the eggs. In the best case, the shelf life of the eggs was almost doubled. After 7 days, the kanamycin+glucose treatment led to a hatching success of 86±1% of the hatchable eggs, while the untreated eggs presented a hatching success of 47±6%. However, long exposure to high concentrations of antibiotics was lethal to the copepod eggs. After more than 30 days of exposure to 100 mg L⁻¹ of oxytetracycline, the survival of the eggs was lower than in the untreated samples. After 45 days, oxytetracycline-treated eggs (100 mg L⁻¹) presented a hatching success of 4–5% while the non-stored eggs still had a hatching success of 9%, and the eggs treated with a lower concentration of antibiotics (10 mg L⁻¹) showed a hatching success up to 21–23%. The size of the nauplii in all trials tended to decrease as the period of cold storage at 1°C increased. We consider that the use of antibiotics at the right dosage to be a means to increase the storage capacity of the Gulf of Mexico strain of A. tonsa eggs, which do not show any capacity to be stored for long periods of time, compared with some other strains. In addition eggs that were between 5 and 7 h old survived longer when stored in the cold than eggs, which were freshly spawned or closer to hatching.     

Effects of Calcium and Magnesium Hardness of Incubation Waters on the Hatching Success of Hybrid Eggs of ♀ Channel Catfish,Ictalurus punctatus × ♂ Blue Catfish,Ictalurus furcatus

Hatching efficiency is generally lower in channel catfish, Ictalurus punctatus × blue catfish, Ictalurus furcatus, hybrid catfish hatcheries compared to hatcheries hatching pond‐spawned channel catfish eggs. Egg quality and hatching water hardness are known variables influencing the efficiency of hybrid catfish fry production in hatcheries. Previous research recommended that at least 60 mg/L hardness had to be contributed only by calcium to optimize the hatching success of hybrid catfish eggs. However, whether the effect of waterborne magnesium in hatching waters facilitates or impedes the hatching success of hybrid catfish is not known. Two trials were conducted to determine the effects of calcium alone or magnesium hardness, in combination with the hatching success of hybrid catfish eggs. Trial 1 showed that if the previously identified minimum hardness criterion of 60 mg/L was met by calcium in the hatching waters, added magnesium had no effect on the hatching success of hybrid catfish eggs. Trial 2 showed that the previously identified minimum hardness of 60 mg/L can be met by either calcium alone or magnesium replacing up to 50% of the total hardness in the hatchery waters for optimal hatching success of hybrid catfish eggs. Calcium provides a specific requirement during embryonic development of catfish. The results from this study can be used to design treatment processes for hatchery water supplies to improve efficiency of hybrid catfish fry production in hatcheries.     

温度对奥尼罗非鱼受精卵孵化和仔鱼活力的影响

研究了温度对奥尼罗非鱼(Oreochromis niloticus×O.aureus)受精卵孵化和仔鱼活力的影响。在盐度为5不同温度(22、24、26、28、30、32和34℃)下,比较观察奥尼罗非鱼受精卵的培育周期、孵化周期、孵化率和畸形率。同时在以上不同温度条件下对初孵的奥尼罗非鱼仔鱼进行耐饥饿试验,测定其不投饵存活系数(Survivalactivity index,SAI)。结果表明:在温度为24~32℃,受精卵孵化率较高(84.3%~91%),温度高于34℃和低于22℃时,孵化率较低。温度与培育周期呈负相关关系,函数关系为y=0.3607x2-26.836x+553.5,R2=0.973。仔鱼生存适宜温度是24~30℃,最适的温度是24~26℃。温度为22℃时,SAI值分别为19.9,但是仔鱼发育的缓慢,部分仔鱼的身体色素一直没有出现,不适合仔鱼的培育。     

野生和养殖曼氏无针乌贼亲体形态、生化组分及其胚胎发育的比较

为优化曼氏无针乌贼人工繁育技术,提高人工增殖苗种的产量与质量,采用实验生态学方法,对比分析了野生和养殖曼氏无针乌贼（Sepiella japonica）的表观形态、生化组分及其受精卵的形态差异,探究了光照周期与受精卵胶质外膜对曼氏无针乌贼胚胎发育的影响。结果显示：野生和养殖曼氏无针乌贼的表观形态、生化组分均存在显著差异,野生群体性成熟规格远大于养殖群体,肌肉和肝脏组织中的脂肪含量显著低于养殖群体（P<0.05）,卵巢中的蛋白质含量则显著高于养殖群体（P<0.05）;养殖亲体所产黑卵在12D12L光照周期条件下孵化率最高,所产白卵在24D和24L条件下孵化率最高,野生亲体所产卵在24D和12D12L条件下孵化率最高;随光照时间的延长,受精卵的平均孵化时间具有先增加后减小的趋势,表明光照周期是影响曼氏无针乌贼胚胎发育的重要因素;实验发现,将受精卵胶质外膜剥离处理后,养殖亲体所产黑白卵的平均孵化时间具有减少的趋势,但孵化率显著下降（P<0.05）。综上所述,建议在曼氏无针乌贼人工苗种生产过程中,尽量选用大规格野生乌贼作为繁育亲体。此外,在受精卵孵化期间,应对孵化池进行适当遮光处理,避免受精卵长时间暴露于强光照环境中,以提高孵化率和仔乌成活率。本实验研究结果可为曼氏无针乌贼人工苗种繁育技术优化提供参考。     

中华绒螯蟹抱卵颜色异常的初步研究

本文对中华绒螯蟹抱卵颜色为异常的粉红色与土黄色进行了分析。实验结果表明,逐渐加入海水与直接排光淡水、加入海水的两种促产方式和较低的交配水温(1.6～9℃)不会造成河蟹抱卵颜色异常,雌蟹的性腺发育状况是产生这种现象的原因,粉红色卵与土黄色卵是由性腺处于Ⅱ、Ⅲ期的雌蟹产的,为受精卵。两种卵胚胎发育正常,孵出的幼体发育也正常,在生产中可以应用。     

冬季温度刺激对克氏原螯虾繁育的影响

通过加温刺激克氏原螯虾(Procambarus clarkii)雌虾在冬季抱卵,并对卵及幼体在不同水温下的发育过程进行观察。结果显示:经过38 d的加温刺激,在26℃下陆续观察到有虾抱卵,18℃以下未观察到抱卵虾,但该水温能促进雌虾性腺发育。雌虾经加温刺激后所抱卵在18℃,21℃和26℃下均能正常孵化出幼虾。18℃,21℃和26℃下孵化时间分别为(39.67±3.06)d,(28.33±2.52)d和(15.00±2.00)d,孵化所需时间随着温度的提升而减少(P<0.05)。孵化的幼虾经45 d养殖后,在18℃,21℃和26℃下体长分别为(1.90±0.25)cm,(2.73±0.38)cm和(3.78±0.70)cm,体重分别为(0.223±0.100)g,(0.688±0.331)g和(2.145±1.272)g。18℃,21℃水温下的幼虾在此生长阶段为非异速生长(b=3),26℃水温下的幼虾为异速生长(b>3)。在3种温度下,幼体生长速度随温度的升高明显加快(P<0.05)。     

Manipulations of Shrimp Embryos: A Viable Technique for the Removal of the Hatching Envelope

The hatching envelope elevated around the spawned eggs of penaeoidean eggs presents a formidable barrier for manipulation of the embryo. By spawning eggs into seawater containing 3-amino-1,2,4-triazole and subsequently passing the eggs through Nitex screening approximately 45 min after spawning, the hatching envelope can be effectively removed with little or no damage to the embryos. The time and extent to which the envelope is removed can be varied. Embryos treated in this manner continue to develop and the method provides a new technique with which investigators can gain access to the surface of the egg or embryo.