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1.
【目的】了解外源人绒毛膜促性腺激素(human chorionic gonadotropin,HCG)诱导黑边石斑鱼(Epinephelus fasciatus)排卵的影响。【方法】以成熟的黑边石斑鱼为研究对象,测量其体长、体质量和肥满度后,在2018年7—8月,使用HCG激素(剂量为200 IU/kg或500 IU/kg)注射分别对6尾雌鱼进行成熟诱导。【结果】在200 IU/kg HCG处理中,注射24 h前有5尾雌鱼的卵母细胞处于第三次卵黄球前期阶段;注射48 h后2尾雌鱼出现核移动卵母细胞,1尾雌鱼的卵母细胞为第三次卵黄球后期阶段;注射60 h后1尾雌鱼出现排卵现象,其余5尾雌鱼均为第三次卵黄球后期阶段。在200 IU/kg HCG处理的排卵个体中,注射时其卵母细胞直径为477.0 μm,注射后60 h卵母细胞的直径增加至624.4 μm。此外,经催产、排卵、受精和孵化后共获得总卵数16 906粒,受精率为68.7%,孵化率为43.0%。而500 IU/kg HCG处理的黑边石斑鱼排卵失败。【结论】使用剂量为200 IU/kg的外源HCG激素可诱导黑边石斑鱼成熟且排卵,但为了提高排卵率、受精率和孵化率,其注射剂量和效应时间还需要进一步调节。  相似文献   
2.
5种石斑鱼遗传差异的RAPD分析   总被引:3,自引:0,他引:3  
运用随机扩增多态性DNA(random amplified polymorphic DNA,RAPD)技术对鞍带石斑鱼(Epinephelus lanceolatus)、驼背鲈(Cromileptes altivelis)、棕点石斑鱼(E.fuscoguttatus)、斜带石斑鱼(E.coioides)和鲑点石斑鱼(E.fario)的遗传多样性及系统发生进行了研究。从120个RAPD随机引物中筛选出扩增效果好的引物19个,分别用于5种石斑鱼基因组DNA的扩增。结果显示,5种石斑鱼平均多态性位点比率(P)分别为64.23%,72.61%,60.34%,69.97%,73.94%;个体间平均遗传相似系数(S)分别为0.8238,0.8110,0.8345,0.8277,0.8064;平均遗传距离(D)分别为0.1762,0.1890,0.1655,0.1723,0.1936;平均Nei基因多样性指数(H)分别为0.1189,0.1364,0.1028,0.1439,0.1648;平均Shannon信息指数(Hi)分别为0.1801,0.1992,0.1530,0.2100,0.2434。5个种间的遗传距离(Dxy)在0.3964~0.6085之间。  相似文献   
3.
根据己公布的神经坏死病毒全基因序列,应用引物设计软件依据Gene Bank所收录的各种石斑鱼神经坏死病毒RNA2基因组全序列选择保守区域,根据Taqman探针引物设计原则,设计Taq Man探针及其引物。采用Taq Man探针技术,并且将假病毒技术构建的含有神经坏死病毒RNA2基因组的MS2噬菌体假病毒作为阳性质控品,建立Taq Man探针检测点带石斑鱼神经坏死病毒的荧光定量PCR方法,拟合标准曲线,能够在病毒检测中进行绝对定量,能检测到10个病毒拷贝模板数,在临床检测中得到很好运用。本研究建立实时荧光定量RT-PCR,有助于日常检验工作,为鱼类神经坏死病毒的筛选和监测提供基础,有助于控制神经坏死病的疫情传播。  相似文献   
4.
斜带石斑鱼病原菌(哈维氏弧菌)的分离与鉴定   总被引:34,自引:3,他引:34       下载免费PDF全文
从患病斜带石斑鱼 (Epinepheluscoioides)肝脏组织分离到EcGY0 2 0 4 0 1菌株 ,经人工感染、回归感染实验证实为致病菌。通过API系统和菌体常规形态特征、培养特性和生理生化反应指标测定以及 16SrRNA测序分析等综合鉴定 ,Ec GY0 2 0 4 0 1菌株为弧菌属哈维氏弧菌 (Vibrioharveyi) ,其半致死剂量LD50 为 2 .7× 10 6CFU/g鱼体重。药敏试验结果表明 ,EcGY0 2 0 4 0 1菌株对利福平、四环素、喹诺酮类及头孢曲松等抗生素较为敏感  相似文献   
5.
利用活菌制剂,以闭路内循环方式净化水质,养殖点带石斑鱼。试验结果表明:3种活菌制剂对NH4 -N的降解率分别为:NMX菌39.0%,科恩菌30.5%,EM菌20.4%;对NO2--N的降解率分别为:NMX菌45.7%,EM菌40.4%,科恩菌13.6%。活菌制剂不仅能调节水质,而且还能促进养殖个体的生长,提高饵料转化率,NMX菌、科恩菌和EM菌试验组日增重分别为5.5 g/尾、5.1 g/尾、4.9 g/尾,而对照组为3.9 g/尾;相应饵料系数分别是1.00、1.02、1.02,对照组为1.06。  相似文献   
6.
Betanodaviruses are the causative agents of viral nervous necrosis (VNN), a serious disease of cultured marine fish worldwide. Virus-like particles (VLPs) are one of the good novel vaccine candidates to control this disease. Until now, betanodavirus vaccine studies mainly focused on the humoral immune response and mortality after virus challenge. However, little is known about the activation of genes responsible for cellular and innate immunity by vaccines. In the present study, VLPs of orange-spotted grouper nervous necrosis virus (OGNNV) were produced in prokaryotes and their ability to enter Asian sea bass cells was the same as native virus, suggesting that they possess a similar structure to OGNNV. VLPs immunogenicity was then determined by intramuscularly vaccinating Epinephelus coioides at different concentrations (1.5 or 15 μg g?1 fish body weight, FBW) and immunizing frequencies (administration once, twice and thrice). A single vaccination with the dosage of 1.5 μg g?1 FBW is enough to provoke high titer antibodies (average 3 fold higher than that of negative control) with strong neutralizing antibody titer as early as 1 week post immunization. Furthermore, quantitative PCR analysis revealed that eleven genes associated with humoral, cellular and innate immunities were up-regulated in the liver, spleen and head kidney at 12 h post immunization, correlating with the early antibody response. In conclusion, we demonstrated that VLP vaccination induced humoral immune responses and activated genes associated with cellular and innate immunity against betanodavirus infection in orange-spotted grouper.  相似文献   
7.
海南“石斑鱼苗网”渔具属性辨析   总被引:1,自引:2,他引:1  
冯波  卢伙胜 《海洋渔业》2006,28(4):346-349
对在2004年7~8月间南海区小型海洋渔具渔法调查中发现的“石斑鱼苗网”的渔具结构、属性、性能和管理进行了分析讨论,研究认为“石斑鱼苗网”属于敷网类,网团型,延绳式。对石斑鱼苗有良好的诱捕效果,从保护资源的角度出发,应对其实施规范管理。  相似文献   
8.
The aim of this study was to investigate the effects of different oils on growth performance and lipid metabolism of the grouper, Epinephelus coioides. Five experimental fish meal‐based isonitrogenous and isolipidic diets were formulated containing either 5.5%‐added fish oil (FO), soybean oil (SBO), corn oil (CO), sunflower oil (SFO) or peanut oil (PO). Each diet was fed to triplicate groups of 20 fish (initial body weight 13.2±0.02 g) grown in seawater at 28.0–30.5 °C for 8 weeks. Fish were fed twice a day to visual satiety. No significant differences in the survival, weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio or hepatosomatic index were found between fish fed the FO or vegetable oils (VO) diets. Dietary lipid sources did not affect whole‐body composition among grouper fed the various diets. Muscle of fish fed the FO diet had significantly higher levels of 14:0, 16:0, 16:1n‐7, 20:5n‐3[eicosapentaenoic acid (EPA)] and docosahexaenoic acid (DHA)+EPA (except for PO fed fish) compared with those of fish fed VO diets. However, the levels of 18:1n‐9, 18:2n‐6 and DHA/EPA ratios in the muscle of fish fed FO diet were significantly lower than those of fish fed the VO diets. The liver of fish fed the FO diet had significantly higher levels of 18:0, 20:5n‐3, 22:6n‐3, n‐3 highly unsaturated fatty acids and DHA+EPA than those of fish fed the VO diets, whereas increases in 18:1n‐9, 18:2n‐6 and mono‐unsaturated fatty acid levels were observed in the liver of fish fed the VO diets.  相似文献   
9.
An experiment to determine the optimal protein requirement of grouper Epinephelus coioides juveniles was conducted in floating net cages (1.5 m × 1 m × 1.5 m). Six isoenergetic fishmeal–casein‐based experimental diets containing 350–600 g kg?1 crude protein (CP) were fed to triplicate groups of 20 fish (10.7 ± 0.2 g) for 56 days. Weight gain (WG) and specific growth rate (SGR) increased with increasing dietary protein level from 350 to 450 g kg?1 and then plateaued above these levels. Feed intake (FI) showed no significant difference among fish fed more than 350 g kg?1 CP. Lowest feed conversion ratio (FCR) was found for fish fed 500 g kg?1 CP but this was not significantly different from that of fish fed the 450 and 600 g kg?1 CP. Lowest protein efficiency ratio (PER) was found for fish fed 550 and 600 g kg?1 CP. Fish fed the 600 g kg?1 CP had the highest body protein and moisture contents but the lowest body lipid content. Body ash content was unaffected by protein level for fish fed >400 g kg?1 CP. Dietary protein level had no significant effect on hepatosomatic index (HSI). Fish fed the 350 g kg?1 CP had significantly lower condition factor (CF) and viscerosomatic index (VSI). Based on broken‐line regression analysis of SGR the optimal dietary protein requirement for E. coioides juveniles was determined to be close to 480 g kg?1.  相似文献   
10.
斜带石斑鱼胚胎及仔稚幼鱼形态发育   总被引:14,自引:4,他引:14       下载免费PDF全文
对斜带石斑鱼(Epinephelus coioides)的胚胎及仔稚幼鱼形态发育进行了观察与研究,详细描述从受精卵到初孵仔鱼的28个具体发育时期的形态特征和发育时间。根据研究观察结果,将斜带石斑鱼胚胎发育划分为卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期。在水温(25±0.5)℃、盐度31.0p、H 7.8的海水中,斜带石斑鱼胚胎历时28 h 30 min完成整个胚胎发育孵化出膜。胚后发育主要根据卵黄囊、腹鳍棘及第二背鳍棘、鳞片、体色的变化分为仔鱼期、稚鱼期、幼鱼期。仔鱼期根据卵黄囊的有无又分为早期仔鱼和晚期仔鱼。在水温24.5~29.2℃,盐度28.8~33.5,pH 7.5~8.5的海水中,培育至36 d,发育最快的斜带石斑鱼结束仔鱼期进入稚鱼期;培育至42 d,发育最快的稚鱼完成变态,成为幼鱼。斜带石斑鱼胚后发育过程中最明显的变化是腹鳍棘与第二背鳍棘以及鳍棘上小刺的长出与收回。  相似文献   
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