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1.
本文就中华卤虫(Artemia.sinica)家系构建的几个关键技术进行了具体的讨论。交配产卵阶段基本参数研究结果表明,多数家系在抱对后24~60小时便开始产卵,平均间隔时间为55.68小时,具有较好的产卵及时性,同时有效地排除了假性交配现象,保证了在第20日龄时测定各性状值后建立家系、统计交配、产卵数据的准确性。各家系产卵情况统计结果表明,以生产2批卵的家系最多,46个,以产卵总量在151~200粒之间的家系最多,26个,产卵总量大于150粒的家系为70个,完全满足家系构建的需要。半同胞家系方面,在全同胞家系获得足够数量休眠卵的基础上,对仍在抱对的家系采用人工分离抱对雌雄个体的方法进行半同胞家系的组建,以便实现半同胞家系构建的同步性。本试验各生产阶段基本参数的获得,对指导中华卤虫构建家系进行遗传选育提供了理论依据。  相似文献   
2.
介绍了用丰年虫卵壳制备甲壳素及壳聚糖的方法及过程,通过傅立叶变换红外光谱仪的检测并与美国标准谱图库检索出的用蟹壳制备的壳聚糖光谱图对照,证实丰年虫卵壳制备的壳聚糖。  相似文献   
3.
4.
卤虫属分类研究进展   总被引:7,自引:0,他引:7  
卤虫 (Artemia)是一种世界性分布的广温耐高盐的小型甲壳动物 ,其自然的生活环境为内陆的盐湖和沿海的盐田。由于卤虫是水产动物苗种生产中十分重要的生物饵料 ,同时也是生物学教学中重要的活体实验材料 ,因此 ,国内外有关卤虫的生物学及其在水产上的应用研究论文很多 ,其中不少涉及到卤虫的分类问题 ,本文就卤虫属分类研究进展作一综述。1 卤虫属的分类地位卤虫属在分类学上的地位为节肢动物门 (PhylumArthropoda) ,甲壳纲 (ClassCrustacea) ,鳃足亚纲(SubclassBranchiopoda) ,…  相似文献   
5.
海洋细菌B177的鉴定及活性物质研究   总被引:2,自引:0,他引:2  
运用卤虫和玉米纹枯病菌为筛选靶标,从中国南海海泥的94株细菌中分离筛选到1株具有杀虫、抗菌活性的海洋细菌B177菌株。卤虫和玉米纹枯病菌筛选模型测定结果表明,当PSA为发酵液时,LD50值最低,为1.3μg.mL-1;当滤纸片加20μL(5mg.mL-1浓度)发酵粗提取物溶液时,抗玉米纹枯病菌抑菌圈直径可达26mm。对B177的形态特征、培养特征、生理生化特征、16S rDNA序列进行了系统的研究,鉴定其为Micrococcus yunnanensis,其16S rDNA GenBank登录号为HQ439904。对其活性物质进行初步分离纯化研究。  相似文献   
6.
There are no specifically formulated dry foods for tench (Tinca tinca L.), which forces farmers to use diets formulated for other fish species. This has major drawbacks, such as high mortality, slow growth, and body deformities. A 120 day experiment was performed with five-month-old juvenile tench (initial mean weight: 0.388 g; total length: 31.78 mm) to evaluate decapsulated Artemia cysts as a supplement to a dry diet for other fish species. Three treatments, differing in the daily supplement, were tested: 1,800 freshly hatched nauplii, 1,800 cysts, and 300 cysts per g of tench biomass. Final survival ranged between 95.3% and 97.9%. Juvenile tench that received the supplement of 1,800 decapsulated Artemia cysts had a specific growth rate (1.28), weight (1.83 g), and total length (52.30 mm) significantly higher than those with the same amount of nauplii. The lowest supplement (300 cysts/g of fish biomass) allowed significantly lower growth and higher condition coefficient (1.40) than the rest. Animals with body deformities (1.06%) were only recorded in the groups that received the lowest cyst supplement. Results showed Artemia cysts are a suitable dietary supplement for juvenile tench, being an advantageous alternative to live nauplii.  相似文献   
7.
The effect of carbon/nitrogen (C/N) ratio manipulation in feed supplements on Artemia production and water quality was investigated in solar salt ponds in the Mekong Delta, Vietnam. It was assumed that development of bacterial bioflocs through C/N manipulation would improve Artemia production and water quality as demonstrated in freshwater and marine aquaculture. Twelve ponds were used for three treatments and the control, in triplicates. Green water (GW) was supplied to all ponds, with the standard Vietnamese procedure of supplying GW and chicken manure (CM) as the control (C/N 1.8). Treatment ponds were supplemented with tapioca (TAP) as carbon source, combined with either CM, pig manure (PM) or rice bran (RB), with C/N ratios of 7.4, 10.5 or 20.1 respectively. After 6 weeks of culture, no single treatment supported both improved water quality and enhanced Artemia production. Overall, improved water quality was observed at C/N 20.1 and higher Artemia production at C/N 7.4. Although external field factors could have interfered with the set‐up, this is the first study on the effect of C/N manipulation in feed supplements in Artemia pond production systems and provides the basis for development of bacterial bioflocs as a technology to improve water quality and Artemia production.  相似文献   
8.
There has been rapid development in the marine foodfishlarviculture technology in Europe since the early eighties,especially in the flat fish, turbot and halibut, and the bass andbream species. The most significant improvements in the eightieswere the introduction of light control, artificial reproductiontechniques, appropriate water treatment and the use of rotifersand Artemia nauplii of specific sizes and in the late eightiesand early nineties the quality enhancement of live food organismsusing specific enrichment techniques. Present research is focusedon the implementation of several microbial techniques to improvethe hygiene of live prey and fish.Many of the modern larviculture techniques being used in marine foodfish could be adapted for application in the ornamental fish industry. For examples, research in the Onamental Fish Section, Primary Production Department, Singapore has demonstrated that the use of freshwater rotifers and Artemia nauplii would enable artificial rearing of Discus in the absence of the parent fish and improve the larval performance of Gouramis and Tetra larvae. The use of such small live food organisms is likely to facilitate breeding of new fish species with small larvae. Research has also indicated that the use of diets containing vitamin C and certain immuno-stimulants improved the stress resistance of guppy. Such techniques would have important application in the fish transport, an important aspect in the ornamental fish industry  相似文献   
9.
Rotifers and Artemia salina nauplii are the most widely used live prey for newly hatched larvae, but they do not always promote optimal survival and growth. Alternative food sources such as copepods, which bypass these inadequacies and promote adequate growth, are needed and they are viewed with considerable interest by the scientific community. The aim of the present study was to test two different diets [rotifers and A. salina nauplii (group A) and a mixture (group B) of rotifers/Tisbe spp. copepods and A. salina nauplii/copepods] during the larval rearing of the striped blenny Meiacanthus grammistes. The analysis of the survival rate, size (total length and wet weight) and metamorphosis time during the larval phase of this species showed that Tisbe spp. administration can significantly improve larval survival and growth and also reduce the metamorphosis time. The results obtained are related to the fatty acid content of the live prey used and are essential in order to improve the captive production of M. grammistes through a closed system and, in turn, to preserve natural stocks.  相似文献   
10.
4种单胞藻对卤虫生长和生殖影响的比较研究   总被引:1,自引:0,他引:1  
以亚心形扁藻、小球藻、湛江等鞭金藻、绿色巴夫藻为饵料,卤虫为投喂对象,建立五个实验组分别进行研究,观察不同饵料对卤虫生长和生殖的影响,结果表明:投喂亚心形扁藻的卤虫生长最快,成活率高,生殖量也最多,其次为绿色巴夫藻组,湛江等鞭金藻的饵料效果最差.混合4种单胞藻投喂的效果也较好.  相似文献   
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