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21.
长牡蛎四倍体诱导的研究 总被引:5,自引:0,他引:5
本文采用长牡蛎三倍体卵子与二倍体精子授精,用0.5mg/dm3CB处理受精卵抑制第一极体排放诱导出四倍体.处理组在担轮幼虫期检测染色体,4个处理组的四倍体分别为13.95%、12.19%、0%和40.00%.处理组3染色体数在24、25条.其中处理组1、3、4获得稚贝(1~3mm),存活率分别为0.49×10-5、212×10-5和23×10-5.处理组1获得稚贝108粒,处理组3获得附着稚贝7万粒,处理组4获得附着稚贝7000粒.文中还就三倍体雌贝怀卵量及四倍体诱导机制进行了讨论. 相似文献
22.
Nice HE 《Marine pollution bulletin》2005,50(12):661-1674
Nonylphenol, a widespread aquatic pollutant with endocrine-disrupting potential has been found to affect sperm motility in the Pacific oyster, Crassostrea gigas (Thunberg). This marine invertebrate, a global aquaculture species, was exposed to nonylphenol at concentrations of 1 and 100 μg l−1 for a duration of 72 h during the period of gametogenesis. Growth was monitored at regular intervals until sexual maturity when sperm motility was assessed. The growth rate of C. gigas remained unaffected by exposure to nonylphenol during gametogenesis. However, the number of individuals with motile sperm was significantly reduced. 相似文献
23.
为探究长牡蛎在繁殖期间的糖原含量与类胰岛素基因(cgMIP123、cgMIP4、cgMILP7、cgILP)和相关转录调控因子(cgPdx)相对表达量的相关性,自2020年5月至2020年10月采集了山东胶南养殖海区的长牡蛎,测定了血糖含量、糖原含量、条件指数、类胰岛素基因相对表达量及环境因子(酸度、温度、盐度)等数据,采用多元统计方法对数据进行分析。logistic回归分析结果显示,长牡蛎配子排放前后血糖含量和内脏团糖原含量具有显著差异。构建的回归模型可以通过血糖含量和内脏团糖原含量准确判断配子是否已经排放,区分度C-index为0.903,Hosmer-Lemeshow拟合优度检验χ2值为9.06,P>0.05,验证结果显示该模型可靠。多元线性回归分析结果显示:条件指数与cgMIP123和cgMIP4基因的相对表达量具有相关性,R2为0.91,P值为0.0076,极显著相关;内脏团和唇瓣组织的糖原含量与ILPs和cgPdx相对表达量具有一定的相关性,其中cgMILP7的相对表达量与内脏团和唇瓣组织的糖原含量呈负相关,cgPdx相对表达量与唇瓣组织的糖原含量呈负相关,cgMIP4和cgILP的相对表达量与糖原含量呈正相关。 相似文献
24.
C-型凝集素(C-type lectin)是一类能识别并结合多糖的免疫蛋白质超家族, 本文首次克隆了一种新型香港牡蛎C-型凝集素基因——甘露聚糖结合凝集素, 并获得了该基因的全长序列, 命名为ChPerlucin。结果显示, ChPerlucin基因cDNA全长577bp, 包括21bp的5′末端非翻译区(untranslated region, UTR)、73bp的 3′UTR, 以及483bp的开放阅读框(open reading frame, ORF), 编码160个氨基酸, ChPerlucin蛋白理论分子量为18kD, 等电点为5.95。ChPerlucin蛋白含有保守的C-型凝集素样结构域(C-type lectin or carbohydrate-recognition domain, CLECT); 邻接法(Neighbor-Joining, NJ)进化树分析表明, ChPerlucin与其他贝类的Perlucin聚为一支, 说明该基因是软体动物Perlucin家族的新成员。qRT-PCR结果显示, ChPerlucin在香港牡蛎所检测组织和各个胚胎发育时期中均有表达; 病原菌刺激后, ChPerlucin表达量显著升高; 利用毕赤酵母真核成功表达了ChPerlucin重组蛋白, 发现ChPerlucin重组蛋白具有抑菌效果。以上结果表明ChPerlucin在香港牡蛎的先天性免疫过程中发挥了重要的作用。 相似文献
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27.
Zhongming Huo Zhaoping Wang Jian Liang Yuehuan Zhang Jianping Shen Tuo Yao Jiaqi Su Ruihai Yu 《中国海洋大学学报(英文版)》2014,13(4):666-670
This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artificial seawater at three different salinities (low, 15; medium, 23; and high, 30) to determine the optimum hatchery and nursery conditions for mass production of the seeds. Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low- and medium-salinities (P < 0.05). The survival rates of larvae and juveniles differed significantly among the three salinity trials, with the highest survival rate observed at the low salinity (P < 0.05). The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15 (P < 0.05), whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70 (P < 0.05). These results indicate that the larvae and juveniles of C. hongkongensis are tolerant to a wide range of salinities (15 to 30), but show better growth and survival at relatively low salinities. Thus, it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C. hongkongensis. 相似文献
28.
东太平洋赤道公海茎柔鱼生物学特性 总被引:1,自引:0,他引:1
根据2013年4~6月在赤道公海探捕期间采集茎柔鱼样本,研究赤道公海茎柔鱼渔业生物学特性。结果表明,不同性别、不同月份,茎柔鱼胴长和体质量组成不同。雌、雄性样本的胴长范围分别为93~495 mm和94~406 mm,优势胴长组分别为260~340 mm和240~320 mm,分别占样本总数72.53%和70.26%;雌、雄性样本体质量范围分别为25~3 900 g和33~2170 g,优势体质量组分别为400~1 200 g和200~1 000 g,分别占样本总数82.71%和87.82%。雌、雄性茎柔鱼净体质量比例分别介于31.69%~80.51%和37.05%~81.35%之间,平均值分别为60.45%和62.73%。协方差分析表明,茎柔鱼胴长与体质量、胴长与净体质量的生长均存在性别间差异,胴长与体质量的生长都最适合用幂函数表示,而胴长与净体质量的生长,雌、雄性样本分别最适合用幂函数和指数函数表示。不同月份茎柔鱼性别比例构成不同,4月、5月和6月性别比例分别为1.87∶1、1.61∶1和1.17∶1,全部样本的性别比例为1.61∶1。不同月份茎柔鱼性腺成熟度的组成不同。不同性别、不同月份间茎柔鱼胃含物等级组成存在差异。 相似文献
29.
Geoffrey B Read 《新西兰海洋与淡水研究杂志》2013,47(2):83-100
Shells of commercially valued bivalves in New Zealand, Crassostrea gigas, Perna canaliculus and Pecten novaezelandiae, are damaged by blister-causing Polydora polychaete species known to be close in morphology to the widely recorded oyster pest Polydora websteri Hartman. Recent New Zealand occurrences are here confirmed to relate to two species, P. websteri, and a second similar species, Polydora haswelli Blake & Kudenov, a new record for New Zealand, previously known only from Australia; the two species are described and compared. The worms have limited distributions, with P. websteri confirmed only for Pacific oysters (C. gigas) in northern New Zealand, although prior reports indicate it may also occur on scallops and have reached the northern South Island. Polydora haswelli has been found only in northern New Zealand, occurring on subtidal mussels and scallops and native oysters (Perna canaliculus, Pecten novaezelandiae, Ostrea chilensis), as well as co-existing with intertidal P. websteri on Pacific oysters. The worms are not present in Foveaux Strait O. chilensis beds, a major source of past oyster exports to Australia. The history of mud-blister worm outbreaks in Australasia is examined. While trans-Tasman exports of live oysters from New Zealand were commonplace during the nineteenth century, there is no evidence that mud-blister worms were present in New Zealand then. The earliest reports only date from the early 1970s and only from northern New Zealand, whereas a century earlier in the 1870s at least one of these pest worms had become widespread along eastern Australian coasts. 相似文献
30.
盐度对近江牡蛎耗氧率、排氨率、O:N 和吸收率的影响 总被引:2,自引:0,他引:2
以半现场流水槽法研究了不同盐度(5、10、15、20、25、30、35)对近江牡蛎(Crassostrea hongkongensis)耗氧率、排氨率、O:N、吸收率的影响,并测定了盐度为20条件下牡蛎耗氧率和排氨率的周日变化.结果表明,近江牡蛎耗氧率、排氨率、O:N先随着盐度的升高而下降,在20左右降到最低,随着盐度继续上升,又升高;而近江牡蛎的吸收率先随着盐度的升高而升高,在20左右达到最高,然后随盐度升高而下降.根据数据得出耗氧率与盐度的拟合方程: y=0.0033x2-0.1161x+1.5523, R2=0.9018;排氨率与盐度:y=0.0001x2-0.0041x+0.0871, R2=0.9889;O:N与盐度:y=0.0016x3-0.0782x2+0.9051x+10.818, R2=0.955;吸收率与盐度: y=-0.0011x2+0.0399x+0.4393.R2=0.9453.一日内,8时、14时、19时、22时4个时间点,近江牡蛎耗氧率和排氨率变化较大,在14时最大,表明该时点其代谢活动最强. 相似文献