插片后珍珠蚌生长性状及其无核珍珠成珠率和大小

为了筛选优质的珍珠蚌插片组合,探究不同种类珍珠蚌相互插片后生长性状间的差异和相关性,以及各组合无核珍珠成珠率和大小的差异,利用三角帆蚌(S)、池蝶蚌(C)和褶纹冠蚌(Z)分别作为供片蚌和育珠蚌,获得9个育珠蚌组合,测量各育珠组合的体质量、壳长、壳高和壳宽,比较9个育珠蚌组合及3个未插片的三角帆蚌、池蝶蚌和褶纹冠蚌对照组在1年后生长性状的差异,对各生长性状相关性进行分析。测量每个育珠蚌所产无核珍珠的数量和大小,计算成珠率和圆度,分析不同组合之间无核珍珠的差异。结果显示,无核育珠手术影响珍珠蚌的生长性能,以三角帆蚌和池蝶蚌为育珠蚌的组合生长性状均优于对照组,S-S育珠组合在以三角帆蚌为育珠蚌组合内生长最优,SC和C-C育珠组合在以池蝶蚌为育珠蚌组合中生长最优,而以褶纹冠蚌为育珠蚌的组合插片后生长性状指标均小于对照组。其中除了池蝶蚌同种插片组合(C-C育珠组合)外,其余各育珠组合壳长与体质量间相关系数均高于其他生长性状间相关系数,C-C育珠组合壳宽与体质量相关系数最大;三角帆蚌和池蝶蚌之间的插片组合(S-S、C-S、S-C和C-C育珠组合)及褶纹冠蚌同种插片组合(Z-Z育珠组合)成珠率较高(91.67%～100%)。S-S、S-C和C-C育珠组合所育珍珠较圆但珍珠大小在各育珠组合内处于中等。研究表明,无核育珠手术改变珍珠蚌的生长性能,不同育珠组合生长性能存在差异,S-S、S-C和CC育珠组合插片后生长性能较好,成珠率高,珍珠较圆但珍珠大小在各育珠组合中处于中等,该结果为探索不同珍珠蚌生长性状差异和相关性及其所产无核珍珠成珠率、大小的比较提供重要依据。     

提高淡水珍珠质量的小结

目前,人工养殖的淡水珍珠,如何提高质量,已成为当前淡水育珠的重要课题。我们从几年来的淡水养殖珍珠的生产实践认识到,人工育珠的质量是受多种因素影响,如育珠蚌的种类,暂养蚌的饲养管理,制片与插片技术,育珠蚌的饲养管理好环等都影响人工淡水珍珠的质量。现就以上几方面谈点粗浅看法。一、育珠蚌的种类淡水育珠蚌的种类,生产上应用较多的是三角帆蚌,褶纹冠蚌,背角无齿蚌,圆背角无齿蚌,珍珠蚌,背瘤丽蚌等。一般来说,以三角帆蚌、褶纹冠蚌育成珠的质量比其他蚌的质量好,尤其是三角帆蚌     

池蝶蚌(Hyriopsis schlegelii)与三角帆蚌(H.cumingii)育珠生产对比研究

本文对两种育珠蚌即池蝶蚌和三角帆蚌进行培育有核珍珠和无核珍珠生产对比研究，结果表明：池蝶蚌育珠性能明显优于三角帆蚌；池蝶蚌育珠蚌的成活率、所育珍蛛层厚度和珍珠质量均高于三角帆蚌的育珠蚌；至2005年4月，池蝶蚌育珠蚌的成活率、珍珠产量和所培育无核珍珠的3级、8、9、10mm以上珍珠比例都高于三角帆蚌的育珠蚌，显示出较大的经济优势和推广潜力。     

小片与蚌间的关系对珍珠质量的影响

本研究采用褶纹冠蚌同一个体自体外套膜小片育珠,结果珍珠质量明显提高。采用三角帆蚌制取外套膜小片植入褶纹冠蚌。结果珍珠质量极差,大多数蚌产不出珍珠;采用褶纹冠蚌制取外套膜小片植入三角帆蚌,结果三分之一的蚌能得到质量高于褶纹冠蚌,产量高于三角帆蚌的珍珠。作者认为供片蚌和受片蚌间相适关系影响珍珠质量,研究如何提高褶纹冠蚌小片在三角帆蚌体内成珠的比率,在生产上是很有意义的。     

三角帆蚌生长性状和内壳色与所产无核珍珠质量的相关性分析

为了研究供片蚌和育珠蚌对无核珍珠质量的影响,以三角帆蚌紫色选育系F₅为材料,在插植无核珍珠前,测量了供片蚌和育珠蚌的壳长、壳高、壳宽、体质量等生长性状,检测了供片蚌内壳色颜色参数L、a、b、dE。经过18个月育珠,测量了育珠蚌的壳长、壳高、壳宽、体质量,计算其特定生长率,检测了育珠蚌内壳色颜色参数L、a、b、dE,测量了育珠蚌所产无核珍珠的颜色、大小、圆度、光泽和产珠量。结果发现,供片蚌生长性状与所产无核珍珠大小、圆度和产珠量相关性不显著(P>0.05)。供片蚌内壳色与无核珍珠颜色相关性极显著(r=-0.400~0.376,P<0.01),供片蚌dE值越大所产紫色珍珠比例越高、dE值越小所产白色珍珠比例越高。育珠蚌特定生长率与所产无核珍珠大小、光泽和产珠量相关性极显著(r=0.237~0.516,P<0.01),相关程度为体重> 壳长> 壳宽> 壳高,育珠蚌特定生长率与所产无核珍珠圆度相关性极显著(r=-0.284~-0.256,P<0.01),相关程度为壳长>体质量>壳宽>壳高。育珠蚌内壳色与所产无核珍珠颜色、大小、圆度、光泽和产珠量相关性不显著(P>0.05)。综合各性状相关性分析,改良供片蚌内壳色可以改良珍珠颜色,改良育珠蚌的生长性状可以改良珍珠大小、光泽、圆度和产珠量。     

褶纹冠蚌优质珍珠的培育

褶纹冠蚌优质珍珠的培育众所周知，优质珍珠大多产于三角帆蚌．但三角帆蚌生长较慢、货源少，易发病并不易控制，故三角帆蚌育珠风险较大。褶纹冠蚌生长快，抗病力强．只要采取一定的措施，同样也能生产出优质珍珠．主要有以下措施：褶纹冠蚌以１—２龄时期生长最旺盛，之...     

一九七五年河蚌育珠简报

一、珍珠生产 2000个育珠蚌饲养两周年，收获人工无核珍珠8．2市斤。其中褶纹冠蚌平均200个左右收获珍珠1市斤；三角帆蚌平均300个左右收获1市斤。     

2种育珠蚌遗传多样性分析

采用RAPD和同工酶凝胶电泳的方法,对三角帆蚌和褶纹冠蚌的遗传多样性进行了分析.结果显示,三角帆蚌群体内的相似度为0.2917,褶纹冠蚌的为0.3636;两者的群体间相似系数为0.6723,遗传距离为0.3277.EST和LDH同工酶在褶纹冠蚌外套膜及内脏团组织中的表达酶谱均比在三角帆蚌中复杂,2种组织相比则内脏团中的表达酶谱比外套膜复杂.三角帆蚌和褶纹冠蚌同作为亲缘关系比较接近的主要育珠蚌种,两者各有优缺点.在珍珠养殖和育种上,一方面要重视野生资源的保护,避免近亲繁殖;另一方面要建立种质资源库,不断筛选出更多更好的优良性状,提高育珠的质量和产量.     

2种育珠蚌遗传多样性分析

采用ＲＡＰＤ和同工酶凝胶电泳的方法，对三角帆蚌和褶纹冠蚌的遗传多样性进行了分析。结果显示，三角帆蚌群体内的相似度为０．２９１７，褶纹冠蚌的为０．３６３６；两者的群体间相似系数为０．６７２３，遗传距离为０．３２７７。ＥＳＴ和ＬＤＨ同工酶在褶纹冠蚌外套膜及内脏团组织中的表达酶谱均比在三角帆蚌中复杂，２种组织相比则内脏团中的表达酶谱比外套膜复杂。三角帆蚌和褶纹冠蚌同作为亲缘关系比较接近的主要育珠蚌种，两者各有优缺点。在珍珠养殖和育种上，一方面要重视野生资源的保护，避免近亲繁殖；另一方面要建立种质资源库，不断筛选出更多更好的优良性状，提高育珠的质量和产量。     

三角帆蚌与池蝶蚌育珠性能比较

三角帆蚌,隶属于瓣鳃纲,真瓣鳃目,蚌科,帆蚌属,是中国特有的优质淡水育珠蚌。三角帆所产的珍珠产量佳,珠质细腻、光滑、色泽鲜艳、形状较圆,但珍珠生长比较缓慢。池蝶蚌与三角帆蚌同属帆蚌属(日本称为池蝶蚌属),是中国大陆近年来从日本、台湾引进的优良珠贝类。与三角帆蚌相比,池蝶蚌具有壳、珍珠层、外套膜较厚,珍珠质分泌能力强等优点。     

Freshwater nucleated pearl quality is influenced by host mussel growth traits in Hyriopsis cumingii

Hyriopsis cumingii is one of the most important freshwater pearl mussels in China. Recently, this species can produce freshwater nucleated pearls of high quality. Here, we investigated whether nucleated pearl quality is influenced by the growth traits of the host mussel or other factors like cultivation period. We implanted host mussels with a spherical nucleus consisting of a small piece of mantle tissue from donor mussels. After 24 and 36 months of culture, host mussel growth traits including body weight and shell length, height, width and weight were recorded. These factors were then correlated with the quality traits of the pearls they produced, such as nacre thickness, size, weight, lustre and colour. Results indicated pearls obtained at 36 months after seeding were significantly larger in terms of nacre thickness, size and weight compared to those harvested at 24 months. In particular, nacre thickness (r = 0.33–0.48, P = 0.00), pearl size (r = 0.39–0.43, P = 0.00) and pearl weight (r = 0.35–0.47, P = 0.00) were showed to be significantly correlated with host mussels shell length, body weight and shell weight at 24 or 36 months. Larger and heavier host mussels tended to produce bigger pearls. In contrast, host mussels did not affect pearl colour. Cumulatively, our results suggest that longer culturing times and a larger host mussel may help produce better quality nucleated pearl. This information can help guide selective breeding programs designed to improve pearl quality produced by H. cumingii.     

Comparative analysis of total carotenoid content in tissues of purple and white inner-shell color pearl mussel,Hyriopsis cumingii

The freshwater pearl mussel Hyriopsis cumingii is the most important mussel species for freshwater pearl production in China. Mussel shell color is an important indicator of pearl quality. The objective of this study was to assess whether total carotenoid content (TCC) in H. cumingii is related to shell color. TCC of different tissues (gonad, gill, hepatopancreas, kidney, axe foot, mantle, and adductor muscle) of purple and white inner-shell H. cumingii was determined by UV–Vis spectrophotometry. The results revealed that TCC ranged from 12.91 ± 0.78 to 56.30 ± 0.74 μg/g. In general, TCC was higher in the hepatopancreas, followed by the mantle, gonad, gill, kidney, axe foot, and adductor muscle. TCC in gonad, gill, hepatopancreas, kidney, and mantle of purple mussels was significantly higher than that of white mussels. TCC in mussel tissues of H. cumingii was significantly different (P < 0.001) with respect to shell color. There were significant positive correlations between TCC in mussel mantle and shell color intensity. Future studies will assess the biological roles of carotenoids in shell color formation.     

四种微藻投喂对三角帆蚌生长、产珠性能、内壳层颜色和微量元素的影响

为筛选三角帆蚌集约化养殖优质的饵料微藻,本实验采用单因子实验方法,探究投喂不同藻(小环藻、小球藻、二形栅藻、旋转单针藻和混合藻)对三角帆蚌生长、产珠性能和内壳珍珠层颜色的影响。结果显示,投喂不同藻对三角帆蚌的生长影响显著,投喂小环藻组三角帆蚌的体质量增重率、壳长、壳宽和壳高增长率最佳。二形栅藻组次之,但壳长增长率略高于小环藻组。小球藻组、旋转单针藻组和混合藻组生长较差。珍珠增重率以小环藻组最佳,显著高于其他4组。小环藻和二形栅藻组珍珠正圆率显著高于旋转单针藻组。不同饵料微藻对斧足和外套膜微量元素含量影响显著,投喂小环藻组斧足中Ca元素含量最高(12 637.30±624.39) mg/kg。不同饵料微藻对内壳色影响显著,小环藻组内壳色亮度最低、色差最小、饱和度较大;混合藻组内壳色亮度最高、色差最大、饱和度最小;二形栅藻组各值处于中间水平。综合考虑,小环藻是三角帆蚌最佳的饵料微藻,二形栅藻次之。     

Effects of integrated combination and quicklime supplementation on growth and pearl yield of freshwater pearl mussel, Hyriopsis cumingii (Lea, 1852)

The effects of integrated combination and quicklime supplementation on growth and pearl yield of a freshwater mussel, Hyriopsis cumingii (Lea, 1852), were examined through a 137-day growout in land-based enclosures. The integrated combinations examined were either mussel, bighead carp and gibel carp or mussel and bighead carp. Each combination was treated either with or without quicklime supplementation. One half of the mussels in each enclosure were grafted with pieces of the mantle epithelium while the other half were not. During the experiment, gibel carp were fed formulated feed while the mussel and bighead carp were fed natural live food. Quicklime was regularly provided in the enclosures as calcium replenishment. The species composition in the integrated system significantly affected growth in shell size and wet weight of the mussels regardless of the graft and pearl yield, while no significant effects of quicklime supplementation were detected. Growth rates in shell size and wet weight of both grafted and non-grafted mussels and pearl yield were slightly higher in the enclosures with mussel, bighead carp and gibel carp than those with mussel and bighead carp, although these differences were not statistically significant. The non-grafted mussel exhibited faster growth in shell size and wet weight than the grafted mussel within the same treatment. Results of the present study indicate that species combination in an integrated system can affect growth and pearl yield of H. cumingii . The species combination of mussel, bighead carp and gibel carp is recommended for commercial H. cumingii farming.     

转录组测序研究三角帆蚌珍珠颜色相关基因

为筛选影响三角帆蚌珍珠颜色的候选基因,采用转录组测序平台Illumina Hi Seq TM2500对蚌壳珍珠层颜色为紫色和白色的三角帆蚌中央膜组织进行高通量测序。所得序列经质控、组装后比对到NR、Swiss-Prot、COG、KOG、KEGG、GO和Pfam数据库中注释,并进行差异基因聚类分析。结果显示,获得干净数据共72 800 581 bp,拼接获得了89 529个Unigene,差异表达基因2644个,其中上调表达基因1323个,下调表达基因1321个。根据GO功能分类可分为分子功能、细胞组分、生物过程等3大类50分支;根据KEGG代谢通路分析可以分为187类。对差异表达基因分析发现,部分基因与色素合成(眼黄素、黑色素、喋啶色素)及金属离子转运相关,还有6个细胞色素P450,3个细胞色素b561和1个细胞色素b560。研究表明,这些基因可能在珍珠颜色形成中发挥作用。     

Evaluation of laser labeling on growth and survival of the freshwater pearl mussel, Hyriopsis cumingii

Laser labeling techniques have been developed for breeding programs in aquatic organisms through this study. This study assessed their use in Hyriopsis cumingii, an important Chinese freshwater pearl mussel. In preliminary studies, H. cumingii juveniles between 55 and 95?days old were labeled by a laser engraving machine. The mortality rate decreased in an age-dependent manner, no differences in growth between treated and unlabeled juveniles at 85 and 95?days of age. Hundred-day-old juveniles were labeled with four different sized labels. The mortality rate and growth inhibition were significantly higher with the largest label size (2.55?cm) compared to the smaller size and control. Four different types of laser intensity were applied to 100-day-old juveniles, but mortality rates and growth inhibition after high current treatments were significantly higher than the lower currents and control. The wing part, center, lower edge, left edge and right edge were labeled in different 100-day-old juveniles. Labeling of the left edge caused higher mortality and growth inhibition than the other sites. No significant differences were found after either side of the shell was labeled compared to the control. All labels remained clear without any deformation after several months. In summary, the optimal strategy for the laser labeling of H. cumingii would be in juveniles >85?days. The label size, laser intensity and positions could affect their growth and survival. There was no difference labeling either side of the shell. This study showed laser labeling is a relatively simple and practical marking method for mussels such as H. cumingii.     

Does electrofishing harm freshwater pearl mussels?

1. Two experiments were carried out in a Scottish river to test the effects of electrofishing on endangered freshwater pearl mussels (Margaritifera margaritifera). 2. In the first experiment, two areas of mussel bed were marked out as treatment and control sites and the former was electrofished using standard equipment. The mussels were examined 10 min, 24 h and 35 days after treatment and their shell valve closure responses, burrowing capabilities and gravidities were recorded as signs of normal ‘functioning’. 3. In the second experiment, individual mussels were marked as treatments and controls and the former were electrofished. These mussels were examined as before. 4. No mortalities occurred and no significant differences in ‘functioning’ between treatments and controls were observed in either experiment. 5. Since no measurable treatment effect could be demonstrated, it appears that electrofishing did not adversely affect the short‐term survival of M. margaritifera. Copyright © 2001 John Wiley & Sons, Ltd.     

Prediction of potential freshwater pearl mussel habitat aids in discovery of a large population of Margaritifera laevis in Iturup Island,Russia

1. Freshwater pearl mussels (family Margaritiferidae) are sensitive to human impact and environmental changes. Large declines in their abundance have prompted studies of distribution and estimations of population densities.
2. Iturup Island, a part of Kuril Islands, Russia, is considered to be within the distribution area of freshwater pearl mussels, but this information is based on only two specimens collected several decades ago. Detailed survey of the island is challenging as most of its territory is nearly impassable.
3. A preliminary analysis of island rivers was carried out prior to the surveys to discover potential freshwater pearl mussel habitats. Based on previous experience from European Russia, freshwater pearl mussel habitat was expected to occur in rivers flowing out of lowland lakes.
4. Live individuals of Margaritifera laevis were found during surveys in one river together with the unionid Beringiana beringiana, which were also found in two other rivers where the predicted habitat occurred. Based on prediction and surveys, the occurrence of freshwater pearl mussels in other rivers of Iturup Island is unlikely.
5. Pearl mussels were concentrated in a small section of the Zmeika River with a population of about 100,000 mussels. Present threats to the population include overharvest of host fish masou salmon (Oncorhynchus masou).
6. Surveys using similar methods can help to reveal unknown freshwater mussel populations on other Kuril Islands and on the mainland.

     

Genetic analysis of early growth traits of the triangle shell mussel, Hyriopsis Cumingii, as an insight for potential genetic improvement to pearl quality and yield

Individual Hyriopsis cumingii were collected from Poyang Lake, Dongting Lake, and Taihu Lake, China, from which 17 paternal half-sib families, including 51 full-sib families, were produced using a nested design. After the cage culture of each family with ten replicates for 57?days, 30 individuals were randomly selected from each cage, totaling 15,300. Four growth traits were measured for genetic analysis in each mussel: shell length, shell height, shell thickness, and body weight. The heritability of each trait was 0.49?±?0.37, 0.27?±?0.29, 0.59?±?0.39, and 0.47?±?0.38, respectively. Phenotypic and genetic correlation between these four traits fell within the range of 0.89–0.95 and 0.97–1.00, respectively. Early growth traits of H. cumingii show sufficient genetic diversity for genetic improvement. Both phenotypic and genetic correlation between the four traits are high, and thus, the modification on one target trait may modify the remaining three traits accordingly.