河蟹育苗三要点

近年来，尤其是２００２年自南向北绝大多数生产场家出现了亲蟹不足的现象，其主要原因是抱卵率低、越冬成活率不高所致。为了保证育苗生产用亲蟹的质量与数量，在亲蟹交配、越冬时应掌握如下技术要点。一、亲蟹选择所谓亲蟹即性腺发育趋于成熟且尚未交配的雌雄绿蟹，当黄蟹脱壳变为绿蟹后，它标志着河蟹已进入性成熟期，雌蟹卵巢发育快，雄蟹精巢也逐渐粘稠，在自然条件下，此时的河蟹已开始生殖洄游，这是挑选亲蟹的大好时机。亲蟹的挑选应到河湖池塘中去精选，不宜在商贩的手中去挑选。具体选择标准应掌握如下几点：①必须为二秋龄蟹；②…     

河蟹交配时机的掌握

一、交配时机掌握不当引起的不良后果１．胚胎发育不整齐。为了赶早苗,亲蟹交配时间一般安排在１１月中旬,甚至更早,此时河蟹虽已由“黄蟹”变为“绿蟹”,但自然环境条件下,此时水温一般在１２℃以上。由于低温刺激不够,性腺尚未真正生理成熟,即交配条件还未成熟。又由于河蟹的卵为易受精卵,不完全成熟也能受精。如果这种受精卵不经过一段休整期,便拿来升温,胚胎发育较迟缓,胚体间的发育也不同步,从而出现了加温时间长,布苗不同步,甚至一只抱卵蟹布苗一周以上,难以按计划成批生产。１９９７年启东某育苗厂,２０００多只抱卵…     

浅谈河蟹人工交配问题

浅谈河蟹人工交配问题关忠志，李秋（丹东市水产研究所）关键词：河蟹，人工交配，环境，温度近年来，河蟹养殖业发展很快，截止１９９４年末丹东地区的河蟹育苗水体已发展到４万多立方米。年需人工交配的亲蟹达２０多万只，这些亲蟹的准备是育苗生产的基础条件，其交配效...     

上海地区河蟹育苗几种不同方式的浅析

本文介绍了上海地区几家主要河蟹育苗场在近几年的生产中,从种蟹交配,越冬到育苗等各个环节的不同方式,比较其各自的优缺点,为今后提高上海地区河蟹育苗的产量、改进育苗的工艺流程提供一些参考资料。     

对河蟹育苗关键因素的思考

对河蟹育苗关键因素的思考葛立军（锦州盐场水产养殖场）在几年来的河蟹育苗中，总结河蟹育苗中的关键因素，将对河蟹育苗产生一定的积极意义。根据我们几年来的育苗实践，提出以下几个较为关键因素与大家共同商讨。一、亲鳖的规格：目前由于亲蟹资源较少，十分忽视亲蟹的...     

河蟹晚期育苗要点及秋季育苗设想

1河蟹晚期育苗的要点1．1亲蟹选择与交配培育晚期苗的亲蟹培育时间相对较长，一定要注意亲蟹的体质。选择优质的长江水系亲蟹大家都是知道的，但亲蟹个体重量最好控制在100－125克。亲蟹蓄养他一般用水泥地，因亲蟹抱卵后脐部会下沉1－2cm，长时间在池中饲养，爪和脐部磨损严重是造成死亡的最主要原因之一。这种情况个体越大越明显，死亡率也就越高，因而个体不易过大。亲蟹进地时间不宜过早，过早进地的亲蟹肥满度不如水温接近10℃时的质量好，因此掌握亲蟹进池时间是重要的一环。进池温度一般水温不低于10℃，过低水温会影响亲蟹的交配，…     

河蟹控温育苗高产试验

为满足对早期蟹苗的需求,进行了河蟹控温育苗高产试验。在８５０ｍ＾水体中,一茬育出大眼幼体３２９ｋｇ,计４６０６万只,平均１ｍ＾３水体出苗量为０．３８７ｋｇ,平均成活率为２１．９３％。通过试验,探索出高产技术是：１）交配前对亲蟹加强饲喂,增加营养积累,促进亲蟹交配;２）交配时把水温和盐度分别控制在１０－１４℃和１８－２２;３）越冬促熟亲蟹期,要投优质鲜活饵料,池水盐度要高于交配时,水温不低于６．０℃     

河蟹肥水育苗与清水育苗比较

目前，在河蟹人工育苗过程中，概括起来主要有两种育苗方式，一种是我国北方地区常用的清水育苗，即从Z1（状功体I期，下同）到出苗间，全部使用处理好的澄清海水，依靠人工饲料进行培育；另一种就是肥水育苗即从动一动全部用一些蟹苗幼体较爱吃的几种硅藻类作为天然饲料，进行生产育苗的方法。相对清水育苗来讲，笔者认为后者优点较多，近年来，江苏沿海采用此方法较多，效益显著。下面将两种育苗方式作简单的比较。一、操作技术1、简易程度不一样肥水育苗的难度要小于清水育苗，如用密度为40万／m’的单细胞藻液水布地，在自然水质条件良…     

河蟹安全越冬管理

冬季来临，当水温降到10℃以下时，河蟹就很少摄食或不摄食，蜇伏在池埂或池底洞穴中，处于休眠状态或半休眠状态，很少活动。为了使河蟹能够安全越冬，除了改善河蟹越冬的池塘环境外，还有必要加强河蟹越冬管理和制订提高河蟹越冬成活率的措施。     

河蟹亲蟹促产及抱卵蟹培育技术要点

河蟹人工育苗中亲蟹促产及抱卵蟹培育是关系到育苗成效的两个重要生产环节。作者通过多年来的生产性试验，亲蟹的抱卵率和抱卵蟹成活率均达９０％以上。促产处理宜在３月上中旬进行（水温在１０℃以上），促产地面积在１０００ｍ２上下，投放亲蟹密度为７５０ｋｇ／１０－１公顷，雌雄性比掌握在２～３：１，待绝大多数雌蟹抱卵后应及时将雄蟹捕出。抱卵蟹培育的关键是防逃、合理投饲及水质管理。     

Optimal temperature and photoperiod for the spawning of blue crab,Callinectes sapidus,in captivity

Like all poikilotherms, the growth and reproduction of blue crab, Callinectes sapidus depends on temperature and season. Warmer water temperatures in the Chesapeake Bay allow for ovarian development and spawning, while colder water temperatures slow their metabolism and reproduction. The current study aimed to identify optimal environmental conditions for inducing reproduction in animals held in long‐term captivity for year round production in aquaculture through environmental manipulations. Temperature and photoperiod were the main environmental factors tested for 25 weeks: 11°C and 21°C, with the following photoperiods: 0L:24D, 8L:16D, 16L:8D and 24L:0D. At 21°C, the females increased spawning frequency, which was arrested at 11°C. Shorter light exposure at 21°C increased spawning frequency, while constant light inhibited and did not produce spawning. Constant dark (0L:24D) at 21°C produced the most (86%) spawns, but yielded poor larval quality. At 21°C with all photoperiod conditions except constant light, the first spawning took 94.8 ± 32.4 days to occur (n = 17). With females producing multiple spawns, the intervals between the first and second spawns and the second and third spawns were 37.7 ± 8.7 days (n = 6) and 31.0 ± 7.1 days (n = 2) respectively. Analysis of our data using response surface methodology (RSM) predicts the following conditions: at 15–19°C and 0–10 hr darkness for maximal survival and at 19–22°C and 0–8 hr darkness for spawning. The number of larvae produced was positively correlated with size (weight) of the female C. sapidus, suggesting the importance of female size in reproduction.     

Aspects in spawning biology and migration of the mud crab Scylla olivacea in the Andaman Sea, Thailand

Abstract  Spawning biology and migration of the mud crab, Scylla olivacea (Herbst), in the Andaman Sea were examined from November 2002 to March 2004 at Klong Ngoa Mangrove area, Ranong Province, Thailand. Mature females were dominant from July to November. The changes in monthly gonadosomatic index of females ranged from 1.9 (±3.3) to 8.2 (±5.8) and size at first maturity was 9.4 cm internal carapace width (ICW). Fecundity ( F ) correlated ICW according to F =3.02 ×ICW^2.98. A total of 1013 female crabs were double tagged with spaghetti and bottom tags. The recaptured rate was 36.7% and showed that females migrated from coastal area to the open sea during the spawning season. A closed season during the north-east monsoon season and a minimum legal ICW size of 10 cm are recommended for sustainable management of the fishery.     

Development and application of crab culture in the development of Chinese mitten crab industry of Shanghai

Chinese mitten crab is a unique aquatic product in China. As a highly nutritious, delicious, and intriguing food, it is deeply loved by consumers. Through field visits and household interviews in Chongming District of Shanghai and Suzhou of Jiangsu Province, the author collected relevant materials and made a detailed analysis of the strengths and weaknesses, opportunities and threats of the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai by using SWOT model. The results show that the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai can adopt growth‐oriented, transformation and upgrading, diversification and defensive development strategies. It is expected to promote the sustainable development of Chinese mitten crab industry in Shanghai through the development and application of crab culture.     

中华绒螯蟹养殖与固城湖水体氮、磷相关性研究

近年来固城湖水环境质量日益恶化的现象呈现明显,为寻求固城湖水环境质量污染原因,本文将利用物料平衡原理,建立氮磷总量的数学模型,计算固城湖中华绒螯蟹养殖每年所产生的氮磷量,经与实测结果验证,该模型是合理可行的。采用Spearman秩相关系数法计算得到,固城湖中华绒螯蟹养殖所产生的氮、磷量与固城湖大湖区、港口和河口的氮、磷量具有明显的相关性。说明固城湖中华绒螯蟹养殖可导致固城湖水体的氮磷总量呈现快速增长。为更好地保护固城湖水生态环境,应严格控制中华绒螯蟹养殖的规模,杜绝中华绒螯蟹养殖产生的有机污水直接排放入固城湖。     

南方糙海参的人工催产与育苗试验

糙海参（Holothuria scabra）是中国南方优质的热带海参经济品种,试验首次成功在国内综合运用升温等多种刺激方法人工诱导糙海参产卵,并进行了批量人工育苗。2010年4~6月,共进行人工催产试验10次,催产亲参243头,5次试验产卵,催产成功率50%,共获得受精卵1 652.72104粒,孵出糙海参幼体1 226.74104头,总体孵化率74.23%;在水温27.5~30.0℃条件下,受精卵完成胚胎发育需要32.5 h;利用其中部分幼体开展后期人工育苗,经过21 d培育,获得糙海参早期稚参（0.1 cm）19.43104头,苗种培育成活率16.7%;经过32 d培育获得大规格后期稚参苗（0.3~0.5 cm）2.46104头,培育成活率2.12%。试验的成功对下一步开展北部湾海域糙海参的天然种群恢复和在华南地区进行糙海参的人工养殖与开发具有重要意义。     

Effects of temperature and photoperiod on hemolymph vitellogenin levels during spawning events of the blue crab,Callinectes sapidus,in captivity

Vitellogenesis is the process of production and uptake of vitellogenin (VtG), the precursor of vitellin (VT = yolk protein), for ovarian development. In Callinectes sapidus, hemolymph VtG levels are positively correlated with ovarian development. We aimed to develop an invasive tool to monitor ovarian development in order to predict spawning. The present study determined the effects of photoperiod and temperature conditions on levels of hemolymph VtG of the females in captivity kept in a closed recirculating system. Hemolymph VtG levels measured using a competitive ELISA correlates positively with temperature (21° versus 11°C) but are negatively correlated with photoperiod (0L:24D and 8L:16D versus 16L:8D and 24L:0D). Also, heavier (larger) females contain more VtG in their hemolymph and produce greater numbers of larvae. At 21°C, the VtG levels show high individual variations and continuously change over time, indicating that VtG production and uptake by ovary may be continuous and dynamic over multiple spawning events in C. sapidus. Microsatellite analysis of these females reveals a great diversity within and between the batches, implying that resident C. sapidus populations in the Chesapeake Bay are genetically dynamic. Such a great genetic diversity could be responsible for the high variation in VtG levels in these females.     

渔光一体养殖模式对中华绒螯蟹肝胰腺和性腺气味品质的影响

渔光一体养殖模式(photovoltaic fishery breeding mode, PM)是一种采用水下养殖、水上发电的新兴环保养殖模式。本研究比较了渔光一体养殖模式与普通池塘养殖模式(common pond breeding mode, CM)养殖中华绒螯蟹(Eriocheir sinensis)在基本营养成分、感官评价和气味品质等方面的差异。对雌蟹肝胰腺和性腺进行人工及电子感官评价,测定挥发性物质的含量,并对气味品质进行综合评价。结果表明,渔光一体养殖模式能提高雌蟹的性腺指数、增加粗蛋白和粗脂肪含量;PM组肝胰腺表现青草味,电子鼻的响应值最高,PM组性腺的青草味和油脂味更明显;在肝胰腺中,鉴定出44种(PM组)和33种(CM组)物质,PM组总挥发性物质的含量[(70.53±2.91) ng/g]显著高于CM组[(16.63±0.73) ng/g](P<0.05),是CM组的4.2倍,其中油脂味和青草味的物质含量更高;而在性腺中,鉴定出了31种(PM组)和47种(CM组)物质,PM组和CM组总挥发性物质含量分别为(68.80±1.86) ng/g和(71.50±4.17)...     

不同增养殖水体中华绒螯蟹一般营养成份比较分析

实验对不同增养殖水体中华绒螯蟹可食部分一般营养成分营养指标进行分析研究,结果显示在中华绒螯蟹成熟的10月,粗蛋白雌、雄蟹分别为19.48%、16.17%,与其他甲壳类水产动物蛋白质含量相当,粗脂肪雌、雄蟹为13.21%、10.91%,显著高于其他甲壳类水产动物。粗蛋白、粗脂肪含量雌蟹大于雄蟹,水份、灰份雌蟹小于雄蟹。不同增养殖水体10月份中华绒螯蟹粗蛋白含量呈现养殖水体(湖泊网围、池塘养殖)大于增殖水体(湖泊放流、长江野生)态势。     

Effect of d-Lys6 salmon sGnRH alone and in combination with domperidone on the spawning of common carp during the late spawning season

The effect of [d-Lys6] salmon gonadotropin-releasing hormone alone (sGnRH) and in combination with domperidone, a dopamine antagonist, on the spawning of common carp, Cyprinus carpio, was investigated during the late spawning season (when mature fish stop spawning under natural conditions when males and females are put together). Fish were induced to spawn by [d-Lys6]-sGnRH salmon gonadotropin-releasing hormone analogue (sGnRH-X) only when injected in combination with domperidone at doses of 10 g kg-1 and 20 mg kg-1 body weight respectively. [d-Lys6]-sGnRH-X alone did not induce spawning at a dose as high as 100 g kg-1 body weight. Fish injected with domperidone alone did not spawn either. These results demonstrate that [d-Lys6]-sGnRH-X in combination with a dopamine antagonist is effective in inducing spawning during the late spawning season.