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实验利用线粒体COI基因和Cytb基因的片段序列分析比较了黑锦鲤(Cyprinus carpio Karasugoi Koi)、三色锦鲤(C.carpio Taisho Sanshoku Koi)、红白锦鲤(C.carpio Kohaku Koi)、黄金锦鲤(C.carpio Kigoi Koi)、全白锦鲤(C.carpio Platinum Ogon Koi)和全红锦鲤(C.carpio Higoi Koi)6个锦鲤(Cyprinus carpio Koi)养殖品系的遗传多样性和系统进化关系。结果显示:基因序列分析得到的单倍型数分别为7、6。6个品系均具有较高的单倍型多样性指数和较低的核苷酸多样性指数。群体间遗传分化系数Fst、遗传距离和AMOVA等结果显示品种间变异高于品种内变异,黑锦鲤和黄金锦鲤间、红白锦鲤和三色锦鲤间不存在显著遗传差异,其余品系间差异显著。根据COI和Cytb基因单倍型构建的品系间NJ系统进化树得到相同结果,黑锦鲤和全红锦鲤遗传关系较近,聚为一支。三色锦鲤、红白锦鲤和黄金锦鲤遗传关系较近,聚为一支。全白锦鲤与其他品系的亲缘关系均较远,单独形成一个分支。 相似文献
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红白:白色底肤上配有红色斑纹的锦鲤,称为“红白”,是锦鲤中最具权威与尊贵的品种,其观赏重点在于红白斑纹的配置、红白质地的优良、体态之雄伟等。大正三色:以红白种锦鲤为基本,配上点状小黑斑者,称之为“大正三色”,其头部无黑斑、并且胸鳍上有黑色条纹为基本条件,与“红白”同为锦鲤之主要代表品种。昭和三色:黑底上有红色及白色花纹,并且胸鳍上有黑色斑纹(元黑)者称之为“昭和三色”,其块状黑斑愈浓且具光泽者为昭和三色之极品,与“红白”、“大正三色”合称为锦鲤之“御三家”。蓝衣:蓝衣是红白与浅黄交配的品种,红色斑纹部分的红鳞片… 相似文献
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赤潮及其对渔业的影响 总被引:6,自引:0,他引:6
海洋生态环境恶化是制约海洋生物资源可持续利用的关键问题,也是阻碍海洋经济发展的重要因素。海洋污染导致生态环境恶化,其中对渔业资源危害最大的就是赤潮,赤潮已成为一种全球性的海洋灾害。近20年来,赤潮的危害日益严重,已受到了许多沿海国家的关注。1赤潮及其成因1.1赤潮基 相似文献
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- 1. Fish assemblages of shallow‐lagoonal biotopes (seagrass beds, coral patches, reef flat and sand) were examined within the Nabq Managed Resource Protected Area (MRPA), South Sinai, Egypt. This protected area supports a small‐scale artisanal Bedouin fishery, managed by gear restrictions and a network of no‐take zones (NTZs).
- 2. Coral patches showed highest species richness and diversity of fish, followed in order by the reef flat, shallow seagrass beds and sandy bottoms.
- 3. There were clear differences in fish assemblages between the biotopes surveyed, little differences between sampling areas and no significant differences in fish assemblages between no‐take and take zones, suggesting species characteristic of these shallow‐water biotopes are dispersed along the coast irrespective of fishing pressure.
- 4. Nine species (Acanthurus nigrofuscus, Asterropteryx semipunctatus, Cryptocentrus caeruleopunctatus, Cheilio inermis, Thalassoma rueppellii, Lethrinus mahsena, Lethrinus nebulosus, Parupeneus forsskali and Pomacentrus trilineatus) had a 95% correlation to the pattern of assemblage distribution, indicating these species are the most important determinants of the fish community.
- 5. Approximately one‐third of fishes recorded appeared to be juveniles, with seagrass beds having a particularly high proportion of juvenile fish, including several commercial species.
- 6. The structure of the fish assemblage and fish size suggests that shallow‐water biotopes in Nabq MRPA may be acting as nursery areas of commercial fish for the Bedouin fishery.
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在对虾养殖中,红体症状最为常见。对虾出现红体症状的原因很多,但多数是由水体的理化因子发生变化而引起的应激反应,如不及时处理,就会导致对虾的免疫力下降,继而发生细菌性疾病和病毒性疾病。现根据本人的生产实践经验,对对虾红体症的发生原因分析如下: 相似文献
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Suwen Chen Lixiong Chen Changbo Zhu Yongjian Guo Yihui Guo 《Journal of the World Aquaculture Society》2014,45(4):487-492
Two experiments were conducted to study Gloiopeltis furcata spore culture with different substrates in the nonreproduction season. Using spores discharged by fertile G. furcata frozen for storage, two experiments were conducted during the nonreproduction season. In the first experiment, G. furcata spores were collected and incubated in aquariums using palm line, polythene line, vinylon line, and three types of plastic sheets (white, ripple, and transparent polymethyl methacrylate) as substrates. In the second experiment, G. furcata spores were collected and incubated in a plastic tank using plastic sheets of different materials (PP, PE, and transparent PVC) and plastic even nets of different mesh sizes (3, 2, and 0.5 cm) as substrates. At the end of the experiment (after 60 d), discs with raised thallus were found on different plastic sheets and white plastic even nets, but no discs were visible on any type of line or on the black plastic even net (3‐cm mesh). The white plastic even net was found to be a suitable substrate for G. furcata spore culture in farms and for sporeling culture in sea. Results presented in this study are expected to aid in the progress of the artificial seeding of Gloiopeltis. 相似文献
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将体质量510~620 g的紫红笛鲷用间氨基苯甲酸乙酯甲磺酸盐麻醉后解剖,取出头肾、体肾、肝脏、脾脏,用干净的刀片居中横切、纵切,印片和涂片用Wright-Giemsa染液染色10 min,观察头肾、体肾、脾脏、肝脏4个组织印片以及外周血涂片。试验结果显示,头肾、体肾、脾脏是其造血器官。头肾能发育生成各类型血细胞,体肾能生成红细胞、淋巴细胞、粒细胞和单核细胞,脾脏能生成淋巴细胞。肝脏中未发现幼稚型血细胞。红细胞发育经过原红细胞、早幼红细胞、中幼红细胞、晚幼红细胞和红细胞5个阶段;原粒细胞发育至早幼粒细胞后,分化为嗜碱性中幼粒细胞、嗜酸性中幼粒细胞和中性中幼粒细胞,最后发育成嗜碱性粒细胞、嗜酸性粒细胞和中性粒细胞;淋巴细胞和单核细胞发育经过原始、幼稚和成熟3个阶段。血细胞在发育过程中,胞体逐渐变小,细胞核逐渐变小,染色质由疏松到致密;粒细胞中,颗粒由少到多。 相似文献
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美国红鱼 (Reddrum )即眼斑拟石首鱼(Sciaenopsocellatus) ,又称红拟石首鱼、黑斑石首鱼、红鼓鱼、黑斑红鲈、斑尾鲈等。原产于美国东南沿海 ,是美国近几年重要商业养殖鱼类 ,也是我国引进养殖的新品种。据报道 ,美国红鱼病害有二三十种 ,本文将已发现的主要病害介绍如下。1病毒性疾病1 .1病毒性红细胞坏死病病原 :属DNA病毒 ,虹彩病毒科 ,对热不稳定。病状 :幼鱼对该病的敏感性大于成鱼。病鱼的鳃和内脏呈苍白色 ,活动无力 ,对外界刺激的反应弱 ,摄食差或拒食。高温季节易发生此病。防治方法 :适当投一些抗菌或抗病毒的药饵 ,以减少因合… 相似文献