992 resultados para Argyrosomus Japonicus, Microsatellites, Primer, Sciaenidae Family


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fully grown oocytes of Apostichopus japonicus have a cytoplasmic protuberance where the oocyte attaches to the follicle. The protuberance and the oolamina located on the opposite side of the oocyte indicate the animal-vegetal axis. Two pre-meiotic centrosomes are anchored to the protuberance by microtubules between centrosomes and protuberance. After meiosis reinitiation induced by DTT solution, the germinal vesicle (GV) migrates towards the protuberance. The GV breaks down after it migrates to the oocyte membrane on the protuberance side. The protuberance then contracts back into the oocyte and the first polar body extrudes from the site of the former protuberance. The second polar body forms beneath the first. Thus the oocyte protuberance indicates the presumptive animal pole well before maturation of the oocyte.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With a "two-way pseudo-testcross" mapping strategy, we applied the amplified fragment length polymorphism (AFLP) markers to construct two moderate density genetic linkage maps for Laminaria. The linkage maps were generated from the 60 progenies of the F, cross family (Laminaria longissima Aresch. x L. japonica Miyabe) with twenty pairs of primer combinations. Of the 333 polymorphic loci scored in 60 progenies, 173 segregated in a 1:1 ratio, corresponding to DNA polymorphisms heterozygous in a single parent, and the other 58 loci existing in both parents followed a 3:1 Mendelian segregation ratio. Among the loci with 1:1 segregating ratios, 79 loci were ordered in 14 linkage groups (648.6 cM) of the paternal map, and 72 loci were ordered in 14 linkage groups (601.9 cM) of the maternal map. The average density of loci was approximately 1 per 8 cM. To investigate the homologies between two parental maps, we used 58 loci segregated 3:1 for further analysis, and deduced one homologous linkage group. The linkage data developed in these maps will be useful for detecting loci-controlling commercially important traits for Laminaria.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

An orange-pigmented, Gram-negative, nonmotile, strictly aerobic and oxidase- and catalase-positive bacterium (SM-A87(T)) was isolated from the deep-sea sediment of the southern Okinawa Trough area. The main fatty acids were i15 : 0, i17 : 0 3OH, i15 : 1 G, i17 : 1 omega 9c, 15 : 0, i15 : 0 3OH and summed feature 3 (comprising i-15 : 0 2OH and/or 16 : 1 omega 7c). MK-6 was the predominant respiratory quinone. DNA G+C content was 35.8 mol%. Flexirubin-type pigments were absent. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SM-A87(T) formed a distinct lineage within the family Flavobacteriaceae, with < 93% sequence similarity to the nearest strain of genus Salegentibacter. Moreover, strain SM-A87(T) could be distinguished from the nearest phylogenetic neighbors by a number of chemotaxonomic and phenotypic properties. On the basis of polyphasic analyses, it is proposed that strain SM-A87(T) be classified in a novel genus and a new species in the family Flavobacteriaceae, designated Wangia profunda gen. nov., sp. nov. The type strain is SM-A87(T) (CCTCC AB 206139(T)=DSM 18752).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

针对目前刺参养殖过程中亟需解决的种质、环境和产品品质之间日益突出的矛盾,本论文从刺参的自身防御和内分泌机制入手,比较系统地研究了环境胁迫与细胞免疫和应激激素之间的作用机理;并从生理和分子的角度对刺参的夏眠机理进行了初步研究,主要研究成果如下: 1. 查阅国内外大量文献资料,较为系统地综述了海参的免疫体系、生态免疫学研究进展、当前夏眠机理的研究状况和刺参夏眠的基础研究。对刺参生态免疫及其夏眠机理研究提出了新的见解和思路。 2. 研究了温度(0、8、16、24、32℃)和盐度(20、25、35)的急性胁迫(72h)作用对刺参免疫指标的影响。刺参体腔液内几种免疫酶类活性受升温胁迫影响显著;而降温胁迫的影响并不显著。高盐胁迫可使刺参体腔液细胞吞噬活性、超氧化物歧化酶和过氧化氢酶活性显著变化,而对髓过氧化物酶和溶菌酶活性都没有显著影响。从这几种免疫指标变化情况来看,温度胁迫对刺参的影响要强于盐度胁迫,且高温胁迫的影响要强于低温胁迫。 3. 研究了温度(8、16、24℃)、盐度(20、25、35)和露空等急性胁迫(24h)作用对刺参体腔液儿茶酚胺类激素含量的影响。急性温度胁迫能够显著影响刺参体腔液内肾上腺素、去甲肾上腺素和多巴胺的含量;而盐度和露空胁迫对刺参体腔液肾上腺素含量、去甲肾上腺素含量以及多巴胺含量都没有产生显著影响。 4. 完成了刺参体腔液几种酶类变化的周年测定(2006年7月到2007年6月)。一年内刺参体腔液内几种酶类变化的转折点为9月份,10月份,1月份,2月份,4月份和5月份。刺参体腔液内几种酶类活性变化与温度和盐度等环境因素并不存在简单的相关关系,因此推测这些显著变化并不是单一温度、盐度等因素作用的结果,还可能与刺参生长、繁殖及其它环境因素的作用有关。 5. 开展了夏眠期间刺参免疫指标的现场研究(2006年7月到11月)。在此期间刺参体腔液细胞总数显著下降;刺参体腔液内免疫相关酶类均在8月份、9月份达到最高值;肾上腺素和去甲肾上腺素的含量均在8月下旬和11月下旬显著升高,而多巴胺含量则没有显著变化。刺参完全进入夏眠的8、9月份,体腔液内各项免疫指标也都具有显著变化,说明夏眠对刺参机体的免疫状态产生影响。 6. 探讨了刺参夏眠前后肠道基因表达的差异(2007年7月至12月)。抑制消减杂交实验结果表明接头连接效率大于50%,说明连接效率较高。消减效率分析结果表明,消减后进行cDNA保守序列扩增比未消减落后约10个循环才能明显看到扩增产物,说明对共同序列的消减效率比较高。利用抑制消减杂交技术成功构建了符合技术要求的夏眠刺参与未夏眠刺参肠道抑制消减杂交基因文库。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本论文选择在我国分离得到的一株有毒赤潮甲藻-塔玛亚历山大藻(Alexandrium tamarense,ATHK株),研究了其对一种我国沿海常见和典型养殖鱼类鲈鱼(Lateolabrax japonicus)的危害机制。首先研究了塔玛亚历山大藻(ATHK)对鲈鱼鳃结构的影响及其溶血毒性; 然后采用腹腔注射的方法,研究了高剂量塔玛亚历山大藻毒素(ATHK毒素:约为1.6×105 细胞,相应PSP为0.886µg STX Equal,相当于每克湿重的鲈鱼PSP注射量为0.0118µg STX Equal)和低剂量塔玛亚历山大藻毒素(ATHK毒素: 约为0.16×105 细胞,相应PSP为0.0886µg STX Equal,相当于每克湿重的鲈鱼PSP注射量为0.00118µg STX Equal)在鲈鱼体内代谢过程中对鲈鱼肝脏、肾脏和鳃组织的超微结构、Na+K+-ATPase活性、肝脏功能和肾脏功能的影响、以及对抗氧化系统酶活性和异生物质代谢酶的影响,以期从不同方面了解塔玛亚历山大藻及其所产水溶性毒素(ATHK毒素)对鲈鱼的毒害效应及机制,为有毒赤潮的有效管理提供一定的科学依据。 塔玛亚历山大藻(ATHK)对鲈鱼鳃组织影响的实验结果表明,该藻使鲈鱼鳃组织出现水肿现象,细胞间隙变大;粘液细胞颗粒不规则,颜色加深,颗粒发生凝集,有板结状;氯细胞线粒体内部基质凝集。不产PSP的一种亚历山大藻(AT-6)也使鲈鱼鳃出现水肿,且使细胞出现一定的固缩现象。显微镜观察发现鲈鱼鳃丝间存在有这两种亚历山大藻细胞。由此推测塔玛亚历山大藻ATHK和AT-6的表面结构可能具有能导致鲈鱼鳃组织水肿的机械作用。对人血细胞溶血实验结果表明塔玛亚历山大藻(ATHK)具有较强的溶血毒性,大小与藻的生长阶段和细胞密度都有一定的关系:指数期的溶血毒性最大,随细胞数目的增多,活性逐渐加大;藻细胞、细胞碎片、细胞内容物都有一定的溶血毒性,其中细胞碎片的活性最大。通过11种(株)产PSP的亚历山大藻、不产PSP的亚历山大藻以及标准PSP的实验结果表明这种溶血毒性是由藻细胞的其它非PSP物质造成的,且这种溶血毒性在产PSP的亚历山大藻中具有一定的普遍性。 塔玛亚历山大藻(ATHK)对鲈鱼组织超微结构实验结果表明:ATHK毒素(约为1.6×105 细胞,相应PSP为0.886µg STX Equal,相当于每克湿重的鲈鱼PSP注射量为0.0118µg STX Equal)能导致鲈鱼组织细胞超微结构发生剧烈的变化,主要表现在:肝细胞细胞膜有肿胀现象,部分膜边缘溶解;细胞质糖原颗粒化;核糖体脱落,仅见滑面内质网;细胞质和线粒体内都出现空泡,且线粒体的嵴状结构也发生变化;核膜溶解比较严重,核质外溢,且异染色质边际化。前肾细胞超微结构的变化主要是淋巴细胞核质出现空泡,核膜有溶解迹象;Ⅰ型粒细胞颗粒膨大,伪足增多且变长;Ⅱ型颗粒细胞颗粒增多,内部出现空腔,细胞膜和核膜溶解,胞质、细胞器和核质外溢。鳃组织中氯细胞的核膜局部溶解,核仁弥散,线粒体膜溶解,微细小管膨大;粘液颗粒膜溶解,内部结构遭受破坏;扁平细胞核膜及线粒体膜几乎全部溶解。因此,我们的结果表明,ATHK毒素能作用于鲈鱼细胞的内膜和外膜系统,使膜发生溶解、脱落等变化;比较注射同样剂量大小ATHK毒素120h和240h时鲈鱼组织超微结构发现,细胞超微结构在一定程度上能够恢复。 ATHK毒素对Na+K+-ATPase活性、肝脏功能以及肾脏功能的影响结果表明,0.16×105―1.6×105细胞范围内的ATHK毒素可以显著影响肝脏和鳃组织中的Na+K+-ATPase,使这两种组织中的Na+K+-ATPase活性出现不同程度的下降; 而且还能够显著抑制肝脏中谷丙转氨酶的活性,最大抑制率为95%。但此范围内的ATHK毒素不能显著影响肾脏中的Na+K+-ATPase活性以及尿素氮含量。因此,ATHK毒素对Na+K+-ATPase活性的抑制则会导致细胞能量的缺失,使细胞进一步发生其它变化,而ATHK毒素对肝脏功能完整性的影响则可能会抑制对蛋白质的分解代谢。 ATHK毒素对鲈鱼肝脏、肾脏和鳃组织中的、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱肝肽过氧化物酶(GSH-Px)以及谷胱肝肽转硫酶(GST)活性变化影响的结果表明:高剂量(约为1.6×105 细胞,相应PSP为0.886µg STX Equal,相当于每克湿重的鲈鱼PSP注射量为0.0118µg STX Equal)ATHK毒素能显著诱导鲈鱼肝脏和鳃组织中SOD、GSH-Px以及GST酶活性,最大变化范围为正常状态下的3-4倍,对肝脏中CAT酶活性具有一定的抑制作用,对鳃中的CAT抑制效应则不显著;但此剂量的ATHK毒素仅对肾脏鳃中的GSH-Px活性有一定的诱导作用,对SOD、CAT以及GST的活性没有显著影响。低剂量(约为0.16×105 细胞,相应PSP为0.0886µg STX Equal,相当于每克湿重的鲈鱼PSP注射量为0.00118µg STX Equal)ATHK毒素也能诱导鲈鱼肝脏和鳃组织中SOD、GSH-Px以及GST酶活性,其在第一个24h内的诱导效果与临界致死毒素剂量相似; 且连续注射低剂量ATHK毒素则对肝脏和鳃中这三种酶活性具有累加的诱导作用,使这三种酶活性的变化范围为正常的5倍;低剂量ATHK毒素对肝脏中CAT酶活性也具有抑制作用,但对鳃中CAT酶活性的抑制作用并不显著。 同样,低剂量ATHK毒素除对肾脏中GSH-Px活性具有一定诱导效应外,对SOD、CAT以及GST都没有显著影响。 SOD、GSH-Px以及GST酶活性的显著升高表明ATHK毒素在鲈鱼体内代谢过程中能诱导鲈鱼产生活性氧自由基,且GST活性的升高则说明作为细胞色素P450依赖的异生物质代谢酶,GST在ATHK毒素代谢过程中可能可以加速ATHK毒素的代谢。推测鲈鱼可以通过这三种酶降低ATHK毒素以及次生毒物活性氧自由基对鲈鱼的危害。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

刺参是目前支撑我国海水增养殖业高效、稳定、持续发展的重要物种之一,但该产业面临着种质匮乏、病害严重、养殖环境局部恶化和产品品质难以保证等诸多问题。本文围绕刺参增养殖过程中的种质苗种问题,以培育耐高温品系为研究目标,在评价我国沿海不同地理群体刺参及其子一代在热刺激条件下HSP70基因mRNA表达差异的基础上,以低纬度地理群体为亲本,经温度刺激后比较了幼体及幼参的生长及HSP70 mRNA表达差异,获得了性状优良的耐高温群体。主要研究结果如下: 1、研究了我国沿海刺参不同地理群体在热激后HSP70基因mRNA的表达差异,比较了在不同温度下不同地理群体幼参的生长特性。青岛、日照和养殖等低纬度群体成参HSP70基因mRNA表达变化较大连、长岛等高纬度群体明显;热激后低纬度群体幼参HSP70基因mRNA表达量较高纬度群体高;高温条件下,高纬度群体子一代成活率低生长。温度升高对高纬度群体生长的影响较大。 2、利用荧光实时定量PCR检测了HSP70基因在不同组织、不同温度、不同时间mRNA水平的表达差异。刺参的各组织都有HSP70的mRNA表达,且对热刺激都有应答。自然水温12℃时,在+12℃温度刺激时刺参的呼吸树中的HSP70 mRNA水平较高;刺参成参、幼参呼吸树中HSP70基因的mRNA水平在热激后6-12h达到最高;低温刺激后HSP70 mRNA下调表达。 3、分别从受精卵和初耳幼体开始在不同温度下进行幼体培育, 27℃以上温度培育的刺参幼体,其生长和成活率显著低于24℃以下温度培育的幼体;不同起始刺激阶段和不同温度都是显著影响因子。从初耳幼体进行高温培育,幼体的变态受到明显影响,26℃以上温度培育幼体的变态率显著低于24℃以下培育温度。 4、以日照刺参为亲本,在26℃培育温度下获得了耐高温群体幼参,并从生长、HSP70mRNA水平的表达差异与常温培育的群体(普通群体)进行了比较。耐高温群体幼参在较高温度下成活率和HSP70mRNA表达水平明显高于普通群体,而二者在特定生长率随温度变化上没有差异。 5、在浙江苍南进行了选择群体耐高温能力和生长验证实验。耐温群体的温度耐受能力提高了0.7℃,进入夏眠时间延后15d左右。耐温刺参群体的特定生长率和成活率在3月温度回升后远高于对照组。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

蓝子鱼科鱼类隶属于鲈形目、刺尾鱼亚目,广泛分布于我国东海、南海及台湾海域。本文根据中国科学院海洋研究所多年来在我国海域采集并收藏的以及部分补充采集的蓝子鱼标本,参考国际最新研究资料,对我国海域蓝子鱼科鱼类进行分类和动物地理学研究,共记录中国海域蓝子鱼科鱼类1属2亚属11种。经研究分析,得到如下结论: 1.中国沿海蓝子鱼科鱼类的多样性问题。国内曾有13种蓝子鱼的分布记录,其中蠕纹蓝子鱼Siganus vermiculatus和暗体蓝子鱼S. punctatissimus仅以前的学者做过名录形式的记载,并无标本收藏,本文中不做介绍。此外尖嘴蓝子鱼Siganus unimaculatus也可能存在于中国海域,有待于进一步研究。目前确定在中国海域有分布的蓝子鱼为11种,约占世界总种数(27)的40%多,种的多样性较高。 2. 形态学比较研究说明,蓝子鱼在体形、体色、牙齿、头骨、椎骨、耳石等特征方面存在种间差异,可作为蓝子鱼科鱼类分类的有效鉴别特征。对于外部形态极其相似的种,可借助内部解剖特征相辅助予以区分。 3.对蓝子鱼动物地理学特点研究分析结论如下:a.中国海域存在的11种蓝子鱼在印度-太平洋海域均有分布,没有地方特有种。b.长鳍蓝子鱼和褐蓝子鱼在我国东海、台湾海域和南海均有分布,褐蓝子鱼在黄海北部亦有分布,种群数量较大;其它9种,除凹吻蓝子鱼仅分布于南海外,均分布于南海及台湾海域,种群数量较小。c.中国海域蓝子鱼种类组成与邻近的菲律宾、马来西亚、印度尼西亚海域比较相似,中国分布的种类在这些海域均有分布,且分布于这一区域而中国没有记录的有5种。与日本相比,种类组成也比较相似,中日共有种达9种,仅分布于中国海域2种,仅分布于日本海域1种。 4. 作者参照国际最新研究结果和较为公认的分类系统Nelson(1994),将蓝子鱼科置于刺尾鱼亚目,而不再使用国内学者长期惯用的蓝子鱼亚目。蓝子鱼科包括一属蓝子鱼属Siganus Forsskål, 1775,两亚属:蓝子鱼亚属Siganus Forsskål, 1775 和罗蓝子鱼亚属 Lo Seale, 1906,同时使全部种名的变动和确定与国际最新研究结果(Woodland, 1990; 2001)取得一致。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文从消化生理学角度出发,研究了刺参营养成分、食物来源以及消化道结构与功能的季节变化,并对养殖水温对刺参消化道结构与功能的影响及与夏眠之间的关系进行了探讨。主要研究结果如下: 1.较为系统地评述了我国刺参增养殖业的现状及存在的问题;对海参的营养成分研究进行了综述和展望;对刺参的消化生理及其夏眠的研究进行了综述并提出了新见解和思路。 2.研究了刺参体壁营养成分的季节变化(2006年7月-2007年6月)。结果表明刺参体壁的基本营养成分及氨基酸、脂肪酸的含量具有显著的季节变化;氨基酸组成全面,平均氨基酸得分(AAS)在75.79-85.17之间,其中8月最高,1月最低;脂肪酸种类丰富,饱和脂肪酸(SFA)相对含量季节变化显著,8月份最高,1月份最低;单不饱和脂肪酸(MUFA)季节变化不显著;多不饱和脂肪酸(PUFA)相对含量具有明显的季节变化,其变化规律与SFA相反,8月份最低,1月份最高;综合分析表明刺参的营养价值在冬季的11月、1月最高。 3.用脂肪酸标志法分析了刺参食物来源组成情况及季节变化(2006年7月-2007年6月)。1月份刺参的主要食物来源是硅藻、鞭毛藻或原生动物、褐藻以及细菌(变形细菌和革兰氏阴性菌),3月份是硅藻、鞭毛藻或原生动物和大型绿藻。6月份大型绿藻在刺参的食物来源中占据较大比重。7月份细菌(噬纤维菌-黄杆菌类、革兰氏阳性菌)和大型绿藻的食物贡献较大。细菌(噬纤维菌-黄杆菌类、革兰氏阳性菌)在8、9月份的食物来源中占较大比重。褐藻和细菌(变形细菌和革兰氏阴性菌)在10、11月的食物贡献较大。 4.现场研究了刺参消化道和消化酶活性的季节变化(2006年6月到2007年6月)。结果表明:刺参的消化酶活性和消化道性状指标均有显著的季节变化。典型夏眠期的9月份,刺参的相对消化道重量(RGM)和Zihler’s 指数分别降低到全年最高值的8.2% 和28.0%。夏眠期间刺参的消化道指数与淀粉酶、脂肪酶、胰蛋白酶、纤维素酶、褐藻酸酶活性都很低,但胃蛋白酶活性很高,且远高于非夏眠期;分析表明Zihler’s指数可以反应刺参的食性,而相对RGM则可反应刺参的摄食状况。 5.研究了养殖水温(7°C、14°C、21°C、28°C,40天)对刺参消化道结构与功能的影响及与夏眠的关系。室内模拟研究结果表明7°C养殖水温下刺参的RGM最高;在7°C和14°C的养殖水温下,RGM没有显著变化。刺参在21°C下的第40天和28°C下的前20天进入夏眠前期,在28°C下的第30-40天进入夏眠期;在夏眠前期和夏眠期,刺参的RGM以及淀粉酶、脂肪酶和胰蛋白酶活性下降,而胃蛋白酶活性显著升高;分析表明高温和积温是引发刺参夏眠不可或缺的外界因素。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文根据中国科学院海洋研究所收藏的豆蟹科标本和国内外相关文献,进行了中国海域豆蟹科的分类学研究。作者克服了豆蟹科分类难度大,研究积累较少,种的界限不清等困难,在短期内初步查清了中国海域豆蟹科种类及分布情况,共记述5亚科12属 40种。发现4新记录属,9新记录种,和豆蟹属1未定种Pinnotheres sp.,丰富了中国海豆蟹科区系内容,列出了共栖种中国海域全部记录过的宿主。 作者对鉴定过程中出现的疑难问题:“中型三强蟹Tritodynamia intermedia Shen, 1935是否为霍氏三强蟹 Tritodynamia horvathi Nobili, 1905的同物异名” 进行了细致比较、研究,否定了通行多年的Sakai(1976)的“T. intermedia Shen为T. horvathi Nobili的次异名”的结论,肯定了二者均为有效种。 对中国海域豆蟹科种类地理分布初步研究表明其分布与日本海域和东南亚海域都有相似之处,但有显著不同:仅发现于中国海域而未见于日本海域的豆蟹属Pinnotheres多达8种:涨腹豆蟹Pinnotheres excussus Dai et al., 1980,球豆蟹Pinnotheres pilulus Dai et al., 1980,锯颚豆蟹Pinnotheres serrignathus Shen, 1932,宽豆蟹Pinnotheres dilatatus Shen, 1932,青岛豆蟹Pinnotheres tsingtaoensis Shen, 1932,海阳豆蟹Pinnotheres haiyangensis Shen, 1932,钝颚豆蟹Pinnotheres obtusidentata(Dai et al., 1980),光豆蟹Pinnotheres luminatus Dai et al., 1980);仅发现于中国海域的三强蟹属Tritodynamia有4种:福建三强蟹Tritodynamia fujianensis Chen, 1979,长腿三强蟹Tritodynamia longipropodum Dai et al., 1980,宽身三强蟹 Tritodynamia dilatatum Yang et Sun,1996和海南三强蟹 Tritodynamia hainanensis Dai et al.g, 1980;而未发现于中国海域的日本特有种多达13种。结果表明这一类群由于共栖和地域分化程度较高乃至地区性特有种数显著较多。 论文通过对豆蟹科系统分类和初步的动物地理学研究,搞清了中国海豆蟹科的种和分布、多样性及其宿主等基本情况。为今后研究豆蟹科种类生物学、生态学特性提供了基础资料。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文采用化学方法诱导了虾夷扇贝Patinopecten yessoensis (Jay)和仿刺参Apostichopus japonicus (Selenka)的多倍体。采用6-二甲基氨基嘌呤(6-dimethylaminopurine)抑制虾夷扇贝极体释放,研究了诱导三倍体的实验条件、技术工艺以及三倍体虾夷扇贝幼虫的生长和培育方法。结果表明,使用6-二甲基氨基嘌呤(6-DMAP)可诱导17.3%-100.0%的三倍体虾夷扇贝面盘幼虫。筛选并优化了生产中操作简便、高效、成活率高的诱导条件,并研究出在扇贝三倍体诱导中批量获得受精卵、处理及培育的技术工艺,对扇贝三倍体的规模化诱导及培育等生产性应用具有较高的参考价值。报道了采用细胞松弛素B(cytochalasin B)、秋水仙素(colchicine)、6-DMAP以及咖啡因(coffeine)等药物抑制虾夷扇贝第一极体(PB_1)释放、PB_1和第二极体(PB_2)释放以及抑制第一次卵裂等方法诱导四倍体的结果。结果表明,CB、6-DMAP和秋水仙素抑制扇贝第一次有丝分裂诱发四倍体的比例低于25%,而采用CB抑制PB_1可有效地诱导产生四倍体,从授精后42min提前到15-22min开始处理,抑制PB_1的放出有助于提高四倍体的比例,在12 ℃,处理开始和终上时间分别在授精后20-22min和60-62min时,面盘幼虫四倍体率最高,为56.5%。对CB处理抑制受精卵PB_1释放的处理组胚胎的染色体分离状况进行了观察研究。对照组受精卵具有19条四分体染色体,经过减数分裂I期(meiosis I)和减数分裂II期(meiosis II),放出PB_1和PB_2,受精卵的发育具有不同步性。处理组受精卵在第二次减数分裂中出现了“三级分离“、“联合二级分离“和“独立二级分离“等特殊的分离类型,初步分析了CB抑制第一极体放出的机理。对三倍体虾夷扇贝的繁殖潜力和卵子的大小进行了观察研究,三倍体扇贝具一定的繁殖能力,三倍体雌贝平均产卵3.26 * 10~6个,而相同壳长二倍体贝为1.45 * 10~7,三倍体产卵量仅为二倍体产卵量的22.5%。三倍体卵子产出后,形状不规则,卵子平均直径为87.25μm,比二倍体大11.7%,卵子体积比二倍体大39.4%。利用CB抑制第一极体释放诱导了虾夷扇贝的四倍体,诱导率为41.5%。首次报道了仿刺参Apostichopus japanicus (Selenka)多倍体诱导的结果。采用紫外线照射的海水成功地使海参分别单独产卵、排精,从而准确地控制了海参的人工授精后处理的时间。采用0.2、0.4mg/L CB 抑制受精卵第一极体释放以及10、20、30和40mg/L 的6-DMAP 分别抑制PB_1、PB_2放出的方法诱导了仿刺参的多倍体。研究了诱导的药物浓度、处理时间以及处理开始时间等,同时对幼体的成活率等进行了探讨。结果表明,2种药物均可诱导仿刺参产生三倍体和四倍体,从效果上看,采用CB抑制PB_1诱导,到达小耳幼体时,可产生9.7%-21.3%的四倍体。6-DMAP抑制PB_2放出诱导三倍体,三倍体诱导率介于7.5%-25.8%之间。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The coelomocytes suspended in the coelomic fluid and occurring in the coelomic epithelial layer of the sea cucumber Apostichopus japonicus (Selenka) (Holothuroidea: Aspidochirota: Stichopodidae) function as mediators of the immune system, trephocytic cells and nutrient transport cells. Types of coelomocytes are characterized based on their morphological and ultrastructural features. Flow cytometry plus light and electron microscopic analyses were conducted in order to characterize the coelomocytes of A. japonicus. Six types of coelomocytes were identified: lymphocytes, morula cells, amoebocytes, crystal cells, fusiform cells and vibratile cells. Within these major categories, several distinctive cell types occurred that might represent developmental stages. The mean +/- SD coelomocyte concentration in the individuals (body length: 10 to 15 cm; weight: 100 to 150 g) was (3.79 +/- 0.65) X 10(6) cells ml(-1). The coelomic fluid contained mainly hyalinocytes (76.69%) and granulocytes (23.31 %).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To investigate the effects of body size and water temperature on feeding and growth in the sea cucumber Apostichopus japonicus (Selenka), the maximum rate of food consumption in terms of energy (C-maxe; J day(-1)) and the specific growth rate in terms of energy (SGRe; % day(-1)) in animals of three body sizes (mean +/- SE) - large (134.0 +/- 3.5 g), medium (73.6 +/- 2.2 g) and small (36.5 +/- 1.2 g) - were determined at water temperatures of 10, 15, 20, 25 and 30 degrees C. Maximum rate of food consumption in terms of energy increased and SGRe decreased with increasing body weight at 10, 15 and 20 degrees C. This trend, however, was not apparent at 25 and 30 degrees C, which could be influenced by aestivation. High water temperatures (above 20 degrees C) were disadvantageous to feeding and growth of this animal; SGRe of A. japonicus during aestivation was negative. The optimum temperatures for food consumption and for growth were similar and were between 14 and 15 degrees C, and body size seemed to have a slight effect on the optimal temperature for food consumption or growth. Because aestivation of A. japonicus was temperature dependent, the present paper also documented the threshold temperatures to aestivation as indicated by feeding cessation. Deduced from daily food consumption of individuals, the threshold temperature to aestivation for large and medium animals (73.3-139.3 g) was 24.5-25.5 degrees C, while that for small animals (28.9-40.7 g) was between 25.5 and 30.5 degrees C. These values are higher than previous reports; differences in sign of aestivation, experimental condition and dwelling district of test animals could be the reasons.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The effect of water temperature on gut mass and digestive enzyme activity in sea cucumber Apostichopus japonicus, including relative gut mass (RGM), amylase, lipase, pepsin and trypsin activities were studied at temperatures of 7, 14, 21, and 28A degrees C over a period of 40 days. Results show that RGM significantly decreased after 40 days at 21A degrees C and markedly decreased over the whole experiment period at 28A degrees C; however, no significant effect of duration was observed at 7 or 14A degrees C. At 14A degrees C, trypsin activity significantly decreased over 10 and 20 days, then increased; amylase and trypsin activity significantly decreased after 40 days at 28A degrees C. However, no significant effect of duration was found on amylase, pepsin or trypsin activities in the other temperature treatment groups. At 28A degrees C, lipase activity peaked in 20 days and then markedly decreased to a minimum at the end of the experiment. On the other hand, pepsin activity at 28A degrees C continuously increased over the whole experimental period. Principle component analysis showed that sea cucumbers on day 40 in the 21A degrees C group and in the previous 20 days in the 28A degrees C group were in the prophase of aestivation. At 28A degrees C, sea cucumbers aestivated at 30-40 days after the start of the experiment. It is concluded that the effect of temperature on the digestion of A. japonicus is comparatively weak within a specific range of water temperatures and aestivation behavior is accompanied by significant changes in RGM and digestive enzyme activities.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

1. This paper investigated the bioenergetic responses of the sea cucumber Apostichopus japonicus (wet weights of 36.5 +/- 1.2 g) to different water temperatures (5, 10, 15, 20, 25 and 30 degrees C) in the laboratory. 2. Results showed that theoretically the optimal temperatures for energy intake and scope for growth (SFG) of sub-adult A. japonicus was at 15.6 and 16.0 degrees C, respectively. The aestivation threshold temperature for this life-stage sea cucumber could be 29.0 degrees C by taking feeding cessation as the indication of aestivation. 3. Our data suggests that A. japonicus is thermo-sensitive to higher temperature, which prevents it from colonising sub-tropical coastal zones. Therefore, water temperature plays an important role in its southernmost distribution limit in China. 4. The potential impact of global ocean warming on A. japonicus might be a northward shift in the geographical distribution. Crown Copyright (C) 2009 Published by Elsevier Ltd, All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fish Lateolabrax japonicus were exposed to anion surfactant sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS) at 1 mg/l, respectively, for 6, 12 and 18 d, with one control group. Liver antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione S-transferase (GST) were determined; brain acetylcholinesterase (AChE) and liver inducible nitric oxide synthase (NOS) activities were also measured. The results of the study indicated that these parameters made different, sometimes, adverse responses to SDBS and SDS exposure, such as the activity of NOS can be inhibited by SDBS and induced by SDS, the different physico-chemical characteristics of SDBS and SDS should be responsible for their effects on enzyme activities. (c) 2005 Elsevier B.V. All rights reserved.