共查询到20条相似文献，搜索用时 78 毫秒
1.
近年来，随着日本对虾养殖规模不断扩大和养殖效益逐年提高，已成为沿海地区新的养殖业亮点，同时也带动了日本对虾人工育苗生产的快速发展，育苗的厂家和规模不断增加，育苗技术有了新的突破，出苗量大幅度提高。然而，诸多因素导致的日本对虾育苗产量不稳定，严重影响了经济效益和养殖业的发展。笔者根据近年的实践，同时借鉴了他人的一些做法，将提高日本对虾人工育苗产量的有关技术措施总结如下，供参考。 相似文献
2.
近年来,随着日本对虾养殖规模不断扩大和养殖效益逐年提高,日本对虾养殖已成为沿海新的养殖业亮点,同时也带动了日本对虾人工育苗生产的快速发展,育苗的厂家和规模不断增加,育苗技术有了新的突破,出苗量大幅度提高.然而,由诸多因素导致的日本对虾育苗产量不稳定,严重影响了育苗单位的经济效益和日本对虾养殖业的发展.笔者根据近年的实践,同时借鉴了他人的一些做法,将提高日本对虾人工育苗产量的有关技术措施总结如下,供参考. 相似文献
3.
三疣梭子蟹是大型食用蟹类，其生长速度快，人工养殖当年可长成商品蟹，是人工增养殖的一个优良品种。但是在我区目前用于养殖的梭子蟹苗种基本上来自于自然海区。为了提高梭子蟹人工育苗技术水平，促进我区梭子蟹养殖产业化的发展，笔者于１９９９～２０００年进行了梭子蟹生产性人工育苗试验，获得了成功并初步摸索出了符合舟山实际的育苗方法。现将梭子蟹人工育苗技术要点归纳如下，供参考。一、亲蟹暂养作为育苗用的抱卵亲蟹，必须活力强，无外伤，附肢健全，卵块坚实，卵块边缘清晰，卵呈淡黄色或棕黄色。不宜选用卵已成熟或接近成熟的… 相似文献
4.
5.
三疣梭子蟹是大型食用蟹类 ,是人工增养殖的一个优良品种。但是我区目前用于养殖的梭子蟹苗种基本上来自于自然海区。为了提高梭子蟹人工育苗的技术水平 ,促进我区梭子蟹养殖的产业化发展 ,笔者于 1 999～ 2 0 0 0年进行了梭子蟹生产性人工育苗试验。试验获得了成功并初步摸索出符合舟山地区实际的育苗方法。现将梭子蟹人工育苗技术要点归纳如下 ,供参考。一、亲蟹暂养1 .亲蟹选择育苗用的抱卵亲蟹必须活力强、无外伤、附肢健全、卵块坚实、卵块边缘清晰 ,卵呈淡黄色或棕黄色。不宜选用卵已成熟或接近成熟的亲蟹 ,以免在运输或入室过程中由… 相似文献
6.
全人工养殖已成为海水养殖业发展的一个新的热点。但由于各地客观条件的差异，养殖技术各有不同，以致养殖产量及效益丰歉悬殊。2003年，结合当地的实际条件，利用改建后的5．87ha的对虾养殖池塘，对三疣梭子蟹不同苗种来源、放养密度以及日常管理技术进行探索试验．为进一步完善、规范三疣梭子蟹全人工养殖技术奠定了基础。 相似文献
7.
三疣梭子蟹养殖技术之一利用地下卤水繁育三疣梭子蟹苗种技术 总被引：1，自引：0，他引：1
三疣梭子蟹全人工育苗技术自二十世纪九十年代初获得突破以来,每年可提供苗种2万千克以上,使三疣梭子蟹的全人工养殖得到了空前的发展。但由于近年来海水污染,苗种产量每年下降,严重阻碍了养殖业的发展。山东省潍坊市有丰富的地下卤水资源。卤水源于海水,生成于海侵期的海退阶段,是 相似文献
8.
<正> 三疣梭子蟹是大型食用蟹类,近几年随着海区自然资源的衰退,人工养殖迅速发展,同时也带动了人工育苗技术的提高。笔者通过几年的实践,总结出一套育苗高产技术措施,现介绍如下。1 育苗设施 利用现有的对虾育苗室进行梭子蟹育苗,水 相似文献
9.
10.
11.
12.
To provide basic nutritional data and theoretical support for the processing and comprehensive utilization of the Chinese mitten crab, we performed a systematic study of the nutritional components of three edible parts, namely the hepatopancreas, gonads and abdominal muscle, of three groups of animals differing in body mass: 75.55 ± 1.56 g, 100.24 ± 2.04 g and 162.27 ± 3.44 g. The results showed that with a greater body mass, the water content was higher, the protein and ash contents were first higher and then lower, and the fat content was first lower and then higher. Amino acids (AAs), essential AAs (EAAs) and the EAA/AA ratio were first higher and then lower, all reaching the standard for high‐quality protein. The most limiting AA was valine. The EAA index was greater than 97 for all three edible parts of the medium‐sized crabs, indicating that crabs in this size group had very high nutritional value. The numbers of detected fatty acids were the same among the edible parts and the three size groups of the river crabs. Among the mineral elements measured, Ca, K and Na were the most abundant and showed a trend of first being higher and then being lower with a larger crab size. Although heavy metals were detected, the Cr, Pb and Cd levels were all within the permissible limits. Therefore, the nutritional quality of the three edible parts was greater for medium‐sized river crabs than for small and large mitten crabs. 相似文献
13.
Can genetic diversity be maintained during mass selection of the Chinese mitten crab,Eriocheir sinensis? 
下载免费PDF全文
下载免费PDF全文 The Chinese mitten crab (Eriocheir sinensis) is an important aquaculture species and food source in Eastern Asia. This study assesses the changes in genetic diversity in successive generations of early‐ and late‐maturing strains of E. sinensis using 30 microsatellite markers with high polymorphism. The mean average number of alleles (N) in the founder population (G0), first generation (G1), second generation (G2) and third generation (G3) of the early‐maturing strain were 18.367, 14.800, 16.400 and 16.533, respectively; while in late‐maturing strain the values were 18.500, 16.267, 14.367 and 16.533 respectively. Likewise, there was a slight decline in average allelic richness (Rs) in the three successive generations. In both strains, the mean observed heterozygosity (Ho) remained relatively constant for the early‐maturing strain and the values were 0.655, 0.667, 0.685 and 0.705, respectively; and for the late‐maturing strain these were 0.665, 0.672, 0.688 and 0.702 respectively. Similarly, the expected heterozygosity (He) remained constant, ranging from 0.823 to 0.854. There was a decrease in effective population sizes (Ne) of the early‐maturing strain with successive generations: values were 492.2, 35.0, 134.7 and 193.2, respectively; while the values in the late‐maturing strain were 1268.5, 75.6, 111.5 and 97.2 respectively. All pairwise population distances were very close in both strains. In conclusion, these results suggest that mass selection of E. sinensis did not significantly diminish genetic diversity although there was a decline for the Ne. Therefore, it is important to maintain sufficient broodstock numbers and a large effective population when following a selective breeding programme. 相似文献
14.
R. Sathiadhas T.M. Najmudeen 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):99-110
Abstract Apart from penaeid shrimp culture, crab farming and fattening and other several diversified aquaculture practices are now emerging as viable ventures in India. About 11 types of crab products are being exported from India with an average unit value realization of US$ 3.73 kg?1, pinpointing its importance in the foreign exchange earnings. An economic evaluation of mud crab culture, fattening and fattening with composite culture of shrimp/finfish has been attempted in this paper. The major operating cost was that of seed and it was higher for crab fattening (87% of the total operating cost). Feed costs were very low compared to that of shrimp farming. Annual profit obtained was US$ 22812.5 ha?1 year?1 for culture and US$ 30820.8 ha?1 year?1 for fattening. Economic indicators such as net profit, rate of return, pay back period and breakeven price indicate that crab fattening/culture is much more profitable than any other coastal aquaculture operations currently in practice, provided hatchery production is established in the country to ensure adequate supply of mud crab seeds. 相似文献
15.
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)... 相似文献
16.
本试验在３２０平方米的土池中进行，３月２９日投放蟹苗２．５公斤，下塘数约３０万只。５月４日出池，饲养３５天，收获五期以上幼蟹１５．６公斤，群体增重５．２４倍；共４２５７０只，个体平均增重４４倍，成活率１４．２％。 相似文献
17.
首次在北部沿海进行了长江蟹人工繁殖试验,报告了亲蟹促产,越冬培育,饵料投喂,水质管理,幼体孵化,幼体培育等全套工艺流程,交配抱卵率达８１％,越冬成活率８４．６％,大眼幼体育成率２２．５％,认为长江蟹,黄河蟹幼体培育方法一致,培养结果,育成率无显著差异,但越冬水深应保持１．５ｍ以上,亲蟹须先进行１５￣２０天强化培育。 相似文献
18.
19.
比较了蛛虫速灭、鱼虫恨和强力混杀3种渔药对桡足类和中华绒螯蟹溞状幼体的急性毒性。试验结果表明,蛛虫速灭对桡足类的96h半致死添加量为0.011mL/m3,鱼虫恨为0.036mL/m3,强力混杀精为0.014mL/m3,蛛虫速灭对桡足类的杀灭能力最强;对中华绒螯蟹溞状幼体Ⅰ期的急性毒性鱼虫恨最大,蛛虫速灭最小。蛛虫速灭在0.18～0.20mL/m3的剂量下,对溞状幼体毒性低,幼体能正常变态,可用于蟹苗池桡足类的控制。强力混杀精对桡足类和中华绒螯蟹溞状幼体的毒性很接近,鱼虫恨对中华绒螯蟹溞状幼体的毒性大于对桡足类的毒性,两者均不适宜在中华绒螯蟹生态池控制桡足类。 相似文献
20.
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。 相似文献