中国海产底栖经济贝类的苗种生产

中国海产底栖经济贝类的苗种生产王一农，张义君（浙江水产学院，宁波３１５０１０）（浙江奉化海产育苗厂，奉化３１５５０７）关键词底栖贝类，苗种生产ＪＵＶＥＮＩＬＥＭＯＬＬＵＳＫＰＲＯＤＵＣＴＩＯＮＯＦＭＡＲＩＮＥＣＯＭＭＥＲＣＩＡＬＢＯＴＴＯＭＳＨＥＬＬ...     

海洋经济贝类遗传图谱的相关研究进展

遗传连锁图谱的构建,是遗传学研究的一个重要领域,它为人们进一步认识生物基因组组成、克隆染色体的基因及定位重要经济性状的主效基因奠定了基础.遗传图谱的建立为基因定位,特别是一些重要经济性状和数量性状位点(QTL)定位,以至最终为克隆这些基因提供基础.     

Comparison of continuous and batch feeding systems on maturation, biochemical composition and immune variables of the oyster Crassostrea corteziensis (Hertlein 1951)

Two feeding systems for maturing oysters were compared, one a continuous feeding system and the other a batch system in which the whole microalgal ration was supplied once daily. The maturation diet consisted in Isochrysis galbana (T-ISO) complemented with an enriched lipid emulsion. Survival and growth did not differ between the feeding systems after 3 weeks of conditioning. Maturation, biochemical composition, fatty acids in membranes and reserves, digestive enzymes activities and immune parameters in Crassostrea corteziensis were analysed. Only oysters fed using the once-daily system had vitellogenic oocytes, whereas the gonad of oysters fed using a continuous-drip system remained immature. Total and differential haemocyte counts were similar between both the systems, but respiratory burst was significantly higher in oysters fed using the once-daily system. Amylase, lipase and trypsin activities in oyster's digestive gland were similar between both the feeding systems. Total lipids, however, differed significantly in oyster tissue in relation to feeding system, with highest level in those fed using the once-daily system, but fatty acid composition in reserves and membrane were similar. No differences were found for biochemical parameters in haemolymph. These results suggest that feeding oysters using a batch, once-daily system allows more rapid initial gonad maturation without affecting general physiological condition and growth.     

Multiple Beneficial Lipids Including Lecithin Detected in the Edible Invasive Mollusk Crepidula fornicata from the French Northeastern Atlantic Coast

The invasive mollusk Crepidula fornicata, occurring in large amounts in bays along the French Northeastern Atlantic coasts, may have huge environmental effects in highly productive ecosystems where shellfish are exploited. The present study aims at determining the potential economic value of this marine species in terms of exploitable substances with high added value. Lipid content and phospholipid (PL) composition of this mollusk collected on the Bourgneuf Bay were studied through four seasons. Winter specimens contained the highest lipid levels (5.3% dry weight), including 69% of PLs. Phosphatidylcholine (PC) was the major PL class all year, accounting for 63.9% to 88.9% of total PLs. Consequently, the winter specimens were then investigated for PL fatty acids (FAs), and free sterols. Dimethylacetals (DMAs) were present (10.7% of PL FA + DMA mixture) revealing the occurrence of plasmalogens. More than forty FAs were identified, including 20:5n-3 (9.4%) and 22:6n-3 (7.3%) acids. Fourteen free sterols were present, including cholesterol at 31.3% of the sterol mixture and about 40% of phytosterols. These data on lipids of C. fornicata demonstrate their positive attributes for human nutrition and health. The PL mixture, rich in PC and polyunsaturated FAs, offers an interesting alternative source of high value-added marine lecithin.     

河蚌结缔组织细胞发生及发育观察

对河蚌外套膜组织学观察发现,外套膜结缔组织发源于细胞聚合体。聚合体细胞发育形成结缔组织细胞及组织构造。外套膜边缘“类聚合体”细胞增殖和发育形成边缘结缔组织。聚合体细胞发育形成不同形状细胞(成纤维细胞和颗粒细胞)。两者不断变化:成纤维细胞积累颗粒最终发育成球状颗粒细胞。球状细胞解体释放颗粒后恢复分泌纤维质状态。纤维物质重新组合排列构成贝体组织骨架,颗粒物质参与贝壳形成。     

First report of white spot syndrome virus in wild crustaceans and mollusks in the Paraíba River,Brazil

The aim of the present study was to investigate the presence of white spot syndrome virus (WSSV) in the Paraíba River, Brazil. Eight sampling sites were established on the bank of the river near water intake areas for the farming of Litopenaeus vannamei. Ten specimens of the shrimp Palaemon pandaliformis and the gastropods Pomacea lineata and Melanoides tuberculatus were collected at each site. Eighty‐one gill fragments from P. pandaliformis, 40 whole individuals of M. tuberculatus and 26 muscle fragments from P. lineata were collected. All samples were stored in microcentrifuge tubes with 95% ethanol (1:10; v:v). Tests were performed at the Potiporã Molecular Analysis Laboratory (state of Rio Grande do Norte, Brazil) for the detection of WSSV using Loop Mediated Isothermal Amplification with the aid of the LAMP WSSV kit (Concepto Azul, Ecuador). Twenty‐nine per cent of P. pandaliformis, 48% of M. tuberculatus and 8% of P. lineata tested positive. The findings demonstrate that WSSV is present in wild crustaceans and mollusks, which may serve as vectors and/or reservoirs of the virus, thereby posing a potential risk to local shrimp farming. This is the first report of WSSV in wild specimens of M. tuberculatus and P. lineata.     

贵州东北部五县陆生贝类资源调查及区系分析*(腹足纲:前鳃亚纲,肺螺亚纲)

笔者对贵州省东北部地区进行了陆生贝类资源调查,获得陆生贝类标本6000多号.经鉴定得69种,分隶于12科31属.区系分析表明:黔东北部地区的陆生贝类以东洋界西南区种类和华中区种类为优势.在69种中,有30种分布于华中区和西南区,约占总数的43.48%;有13种分布于华南区、华中区和西南区(即东洋界),约占总数的18.84%;有9种仅分布于华中区,约占总数的13.04%.将本调查结果与贵州南部地区陆生贝类物种进行比较,发现两地的种类差异明显.     

无棣贝壳堤岛与湿地自然保护区海洋药用贝类资源的调查

对无棣贝壳堤岛与湿地国家自然保护区进行实地调查,采集贝壳样品,并且进行鉴定。参阅相关文献,结合最近的研究进展,对该区的海洋药用贝类资源进行了总结。     

Purification and characterization of transglutaminase from squid gill

ABSTRACT: The present study used squid gill as a source of transglutaminase (TGase) because it has extremely high TGase activity compared with other tissues. The enzyme was purified using successive chromatographies of Sephacryl S-300 and hydroxyapatite columns. The yield and purification-fold of the enzymatic activity was 12.6% and 14.1-fold, respectively. The molecular mass of the purified enzyme was estimated to be 94 kDa by using sodium dodecylsulfate–polyacrylamide gel electrophoresis analysis. Enzyme activity was enhanced 15-fold with an increase in NaCl concentration. Although the activity was dependent on Ca²⁺ concentration, it was not sufficiently activated even by 50 mM CaCl₂ in the absence of NaCl, but could be fully activated with 10 mM CaCl₂ in 0.7 M NaCl. However, in the absence of substrates, the enzyme was rapidly inactivated. The pH and temperature optima of the enzyme were approximately pH 8.0 and 20°C, respectively. It was stable in the absence of Ca²⁺ at pH 7.5–9.0 and had a rate constant (K _D ) of 1.6 × 10^–5 s^–1 for thermal inactivation at 50°C. These results in which squid gill TGase could be activated at higher concentrations of Ca²⁺ and NaCl than at a physiological concentration, suggest that contact with seawater or body fluid seems to activate the enzyme if the tissue is disrupted.