摘要:用原位杂交和免疫细胞化学技术,对服用17-β雌二醇实验组和对照组幼年鲻脑各部和性腺进行芳香化酶的定位.结果发现,芳香化酶转录物和特异性蛋白在幼年鲻端脑(嗅球和大脑)、间脑、中脑和小脑是丰富的.在性别未分化时,芳香化酶免疫活性细胞在幼鲻脑各部的分布密度有显著的差异.在嗅球,对照组芳香化酶免疫阳性细胞的分布密度高于实验组,而在间脑、中脑和小脑实验组免疫阳性细胞数量比对照组多1～3倍,特别是下丘脑视前区芳香化酶的免疫阳性细胞数量尤占优势,提示芳香化酶在幼年鲻性分化中可能起关键的作用.另外,在性分化后,芳香化酶免疫活性还定位在卵巢颗粒细胞和精巢间质细胞与足细胞.同时,免疫阳性物质也定位在卵巢和精巢的生殖细胞.这些结果揭示了17-β雌二醇诱发幼鲻雌性化的机制可能是通过芳香化酶的介导,本研究首次提供形态学新的证据.最后,文中还讨论了芳香化酶在鲻性腺发育中可能的生理作用.

摘要:从97个10碱基随机引物中筛选出30个多态性引物,对黄河鳖、淮河鳖、洞庭湖鳖、鄱阳湖鳖及太湖鳖5个群体共100只个体进行RAPD分析.结果表明,中华鳖的遗传多样性较丰富.表现在:(1)在获得的341条RAPD扩增带中,有234条(68.6%)呈现多态性;2个引物有可明显地反映种群差异的扩增带,其中S105扩增的1408bp在黄河鳖的出现频率仅为20%,而在另外4个群体的出现频率达80%～90%;S37扩增的438bp在5个群体的出现频率大小为:黄河鳖85% >淮河鳖65% >洞庭湖鳖55% >鄱阳湖鳖40% >太湖鳖20%,呈现出从黄河到淮河到长江、从长江的中游到下游逐步降低的遗传渐变现象;(2)多态位点比例(P)的大小顺序为:太湖鳖59.25%>洞庭湖鳖56.52%>鄱阳湖鳖55.80%>淮河鳖55.03%>黄河鳖54.43%,但5个群体间的差异不显著(F=0.644黄河鳖0.771>鄱阳湖鳖0.768>洞庭湖鳖0.750>太湖鳖0.722,其中太湖鳖与黄河鳖、淮河鳖、鄱阳湖鳖3个群体间的差异显著(P <0.05);(4)分子方差分析(AMOVA)表明,黄河鳖与淮河鳖、洞庭湖鳖及鄱阳湖鳖3个群体间,太湖鳖与黄河鳖、淮河鳖2个群体间有极显著的遗传分化(P<0.001);(5)根据遗传距离,用UPGMA 和NJ法进行聚类分析表明:黄河鳖与淮河鳖、洞庭湖鳖与鄱阳湖鳖分别先聚在一起,最后再与太湖鳖聚类,显示太湖鳖在基因组上与其它4个群体鳖存在明显歧化.

摘要:为了探讨不同的交配亲本数对鲍养殖群体遗传结构的影响,实验中对两个皱纹盘鲍自交群体SS(亲本数少)和LS(亲本数多)及两个皱纹盘鲍(♀)?日本盘鲍(♂)的杂交群体SH(亲本数少)和LH(亲本数多)进行了位点频率和遗传结构的AFLP标记分析.研究表明,自交组中亲本数少的SS群体的总位点数少于LS群体,后者的一些低频位点在前者中丢失,同时群体的位点频率发生漂移,SS的低频位点数目减少而高频位点略有增加.另外统计了各群体的相似指数和杂合度,发现SS群体的相似指数低于LS,而杂合度高于LS群体.在杂交组两群体(SH,LH)中位点数目频率、相似指数和杂合度变化趋势与两自交群体相似.两组结果均表明群体的亲本数减少会引起一些低频位点丢失及位点频率发生漂移,同时亲本数过少会导致群体的杂合度暂时升高.

摘要:研究了利用紫外线诱导栉孔扇贝雄核发育的条件.表明紫外线(254 nm)对卵子染色质失活是有效的.在强度为2.8mW?cm-2?s-1的紫外线下照射20 s的卵子与正常精子混合后能保持一定的受精率(60.2%),且D形幼虫发生率为0.染色体检查结果显示此时单倍体率最高(49.2%).说明在强度为2.8mW?cm-2?s-1的紫外线下照射20 s是获得雄核发育单倍体的适宜条件.研究发现受精率和D形幼虫发生率随照射时间的增加而下降,遗传失活的卵子与正常精子受精后其胚胎发育至D形幼虫前期停止.实验中各处理组均出现非整倍体.出现的原因可能由于紫外线照射剂量对卵子染色体遗传失活的作用程度不同以及DNA的光修复.

摘要:在实验室条件下利用放养密度和放养时间构建组间差异,模拟养殖过程中草鱼所面临的拥挤胁迫.胁迫第7、14、30、60d后采样测量免疫指标.结果表明, 高密度组(80g?L-1)的血清溶菌酶活性在胁迫后开始升高,并于14d时达峰值, 以后逐渐下降,呈倒"U"型趋势.血清杀菌活性随放养密度的剧增而锐减(P<0.005).白细胞比容在各组间未显示明显差异.而在30d和60d所测的高密度组草鱼的头肾巨噬细胞吞噬百分率和吞噬指数结果显示,高密度组低于对照组(P<0.05).60d后用嗜水气单胞菌进行攻毒实验,高密度组死亡率高达75.0%,中密度组也达到了63.6%,而对照组只有25.0%.同期所测的脾脏脏器系数显示无论高密度组还是中密度组均显著低于对照组(P<0.01),且经解剖和正常鱼对比,发现其脾脏已明显萎缩.各实验组血清皮质醇浓度均在胁迫初期达到最大值,随后降低,至实验后期基本恢复到正常水平.

摘要:条斑紫菜壳孢子经室内10～80d培养后长成的叶状体分别被酶解成单个细胞,后者在液体培养基中发育成正常叶状体、畸形叶状体、细胞团、性细胞囊等10种不同类型的再生体,它们的形态与结构、细胞排列与大小,放散单孢子难易程度及最终发育结果等均不同.来自日龄不同的种藻的细胞,其再生体类型的数目和各类再生体的百分数不同.当种藻日龄为10～30d时,在它们的单离细胞再生体中出现了极少的细胞团,正常叶状体和具假根畸形叶状体的百分数随着种藻日龄的增加,急剧减少,但不具假根的畸形叶状体百分数却随着种藻日龄的增加而增加.当种藻日龄大于40d以后,它们的单离细胞就几乎不能直接再生成正常叶状体.随着种藻日龄的增加,细胞再生体中不具假根的畸形叶状体百分数也显著减少,而细胞团的百分数急剧上升,精子囊和果胞子囊的数量也逐渐上升.来自同一藻体不同部位的细胞,在它们的再生体中,随着细胞所处藻体部位的上移,正常叶状体和畸形叶状体的百分数急剧减少,而细胞团百分数却不断增加.上述结果说明,在离体条件下,条斑紫菜叶状体的单离细胞发育成不同类型的再生体,是由于它们在种藻里处于不同分化阶段的缘故;同时,初步得出在条斑紫菜叶状体的发育过程中,从壳孢子细胞分化成性原细胞的过程可分为8个不同的分化阶段.

摘要:在以酪蛋白和明胶为蛋白源的精制饲料中添加不同浓度梯度的维生素D,并以海带为对照组饲喂皱纹盘鲍幼鲍103d.结果表明:幼鲍的生长及软体部水分,脂肪和蛋白质含量受到饲料中维生素D添加水平的影响显著,但成活率不受饲料中添加水平的影响;饲料中适量添加维生素D可以提高幼鲍软体部碱性磷酸酶的活力,但饲料中缺乏或过高水平的维生素D导致幼鲍软体部碱性磷酸酶活力的降低;贝壳中灰分及钙、磷含量受饲料中维生素D添加水平的影响显著.以增重,蛋白质增量和软体部碱性磷酸酶的活力为指标,幼鲍饲料中维生素D的适宜含量为100IU?(100g)-1饲料.

摘要:用室内生态实验法测定了南美白对虾幼虾在不同盐度(5,15或25)和水温(20～23℃,25℃,30℃或33℃)下摄食水丝蚓的能量收支方程.在盐度5～25时,随盐度降低,对虾的能量转换效率升高,同化率降低.在盐度为5时,K1最高(29.02%), 同化率最低(77.89%).对虾具补偿机制来补偿调节渗透压的能耗.盐度对同化率的影响,主要是通过影响呼吸代谢实现的.对虾的特定生长率(y)(%?d-1)随水温(X)(℃)上升而增加,其关系式为:y=0.0168LnX 0.0831 (R2=0.9324).对虾在较高温度下生长快,主要是增加绝对摄食量,提高吸收效率,减少粪便排泄量.在相同温度下,变温时对虾的摄食量高于恒温时.

摘要:研究了流水轮虫培育池(14#)、静水轮虫培育池(15#)和轮虫饵料培养池(11#)中不同粒级浮游植物,特别是超微藻类对浮游植物叶绿素和初级生产力的贡献.结果表明,在14#池中,超微藻类、微型藻类和小型藻类的叶绿素a含量分别占总叶绿素a含量的3.7%、82.9%和13.4%.各粒级浮游植物初级生产力分别占总生产力的13.6%、66.0%和20.4%.在11#池中,超微藻类、微型藻类和小型藻类的叶绿素a含量分别占总叶绿素a含量的4.5%、16.1%和79.4%.各粒级浮游植物初级生产力分别占总生产力的9.0%、78.9%和12.1%.在15#池超微藻类、微型藻类和小型藻类的叶绿素a含量分别占总叶绿素a含量的4.7%、22.3%和73.0%.各粒级浮游植物初级生产力分别占总生产力的12.4%、60.8%和27.8%.水体中的初级生产力主要是由微型藻类提供,占总量的60.8%～78.9%,在轮虫培育池生态系统中微型藻类是主要生产者.

摘要:A 562day feeding trial was conducted to evaluate the potential of replacing white fish meal (WFM) with fermented soybean meal ( FSBM ) and soybean meal ( SBM ) in experimental diets for juvenile grouper Epinephelus coioides of initial weight 9. 4 ?0. 1g. Six The control diet (diet 5) contained 68 % of WFM as a sole (1. 5m ?1misonitrogenous diets were formulated to contain 52 % proteinand 12 %lipid. WFMwasreplacedbyFSBMatfourinclusionlevelsof 28 %, 21 %, 14 %and 7%(diets 124) . SBM was tested at one level of 20 % (diet 6) . protein source. Grouper juveniles were cultured in the floating net2cages ?1. 5m) and fed to satiation once daily. Weight growth (WG) and special growth ratio (SGR) were maximized when fish were fed with a combination of diet containing 14 % FSBM and the control diet , respectively. Feeding efficiency (FE) and protein efficiency ratio (PER) decreased with increasing inclusion of FSBM. whole body composition, HSI and VSI. 7 % FSBM and 63 % WFM but they were not significantly different from fish fed with the FSBM and SBM substitutes had no significant effect on At the same inclusion level , fish fed the diets containing 21 % FSBM had higher growth , FE and PER than fish fed the 20 % SBM diets , indicating that FSBM was a kind of better protein source for fish growth than SBM. Based on broken2line regression analysis of WG ( WG versus replacementlevelof WFMwithFSBM),10 %of WFMcanbereplacedbyFSBMwithnoeffectongrowth, FE, PER and body composition of Epinephelus coioides.

摘要:从患病毒性神经坏死病的斜带石斑鱼(Epinephelus coioids)的头部提取总RNA,根据已发表的神经坏死病毒外壳蛋白基因设计引物进行RT-PCR扩增,得到预期大小的基因片段.将此基因片段转入pET载体进行序列测定和分析,结果表明:编码斜带石斑神经坏死病毒(Orange-spotted grouper nervous necrosis virus,OGNNV)外壳蛋白基因的阅读框核苷酸数为1017bp,编码338个氨基酸;基因的核苷酸序列与野田村病毒科(Nodaviridae)的几种病毒的外壳蛋白基因序列比较结果显示,该病毒与β野田村病毒属(Betanodavirus)中的赤点石斑神经坏死病毒(red-spotted grouper nervous necrosis virus,RGNNV)的同源性最高(99%),说明该病毒株是RGNNV血清型的成员.

摘要:对不同类群的九孔鲍细胞与体液免疫机能进行比较,结果表明,不同类群的九孔鲍免疫机能具有显著的差异性,复壮鲍(养殖10个月,个体大小为51.8～59.2mm)细胞与体液免疫机能都明显高于退化鲍(养殖20个月,个体大小为37.4～43.1mm)(P<0.01),与野生九孔鲍(个体大小为67.7～76.7mm)相比,复壮鲍细胞免疫机能略高于野生鲍,体液免疫机能则明显低于野生鲍.九孔鲍血细胞在吞噬活动中具有呼吸爆发产生活性氧的功能与特点,活性氧的产生与九孔鲍自身生理、环境温度以及异物数量等因素有显著的相关性(P<0.01).环境温度由25℃下降至18℃,九孔鲍的细胞与体液免疫机能都有明显的下降.退化鲍在25℃和18℃条件下血淋巴液的抗菌活力水平差异性不明显.酚氧化酶存在于九孔鲍血淋巴液中,但其活性水平不高,在各类九孔鲍之间的差异性也不明显,不能确认为九孔鲍的主要体液免疫因子.

摘要:用200尾10.8?1.2g的草鱼作实验性镉中毒实验.实验分为4组,每组50条.实验各组水中镉含量分别为:1/10 LC50组80μg?L-1,1/50 LC50组16μg?L-1,1/100 LC50组8μg?L-1,对照组为<1μg?L-1,实验期120d.研究内容为草鱼镉中毒时肝胰脏、肾脏、骨代谢生化指标与病理变化.结果表明:(1)草鱼镉中毒的24h LC50为800μg?L-1;(2)各组草鱼的死亡率分别是64%,24%,20%,4%; (3)实验各组草鱼肝胰脏、肾脏和脊椎骨镉含量(湿重) 较对照组极显著升高 (P<0.01); (4)实验各组草鱼血浆中谷草转氨酶、碱性磷酸酶、胆固醇、甘油三酯、葡萄糖均较对照组明显升高,而总蛋白则下降明显(P<0.05); (5)实验各组草鱼脊椎骨中钙含量(湿重)较对照组显著减少(P<0.05),血清中钙、磷、镁含量显著减少(P<0.05); (6)病理学变化主要为:肝胰脏和肾脏严重受损,发生颗粒变性、水泡变性和脂肪变性与溶解坏死,脊椎弯曲、鳃丝塌陷且骨化不全.透射电镜下,肝细胞、肾小管上皮细胞内线粒体肿胀、嵴断裂、溶解;肾小球基底膜节段性增厚.

摘要:Abalones are important farming species with a high economic value. They have already been farmed for more than 50 years. As problems and new requirements rose continuously in culture industry of abalone, studies on genetic and breeding techniques are needed to improve characteristics and to gain new traits. This review concentrates on advances in genetics and breeding techniques in abalone. As for genetic studies, karyological analyses, allozyme, DNA markers and genetic diversity were reviewed. So far, karyological analyses in abalone have been performed in 12 species that can be divided into three groups according to the chromosome number. In some economically important species, loci of allozymes and microsatellites have been isolated and applied to investigate the genetic structure of natural and hatchery populat ions and to identify the result of chromosome set manipulat ion, but the related reports are only a few yet. The resultsof investigation with DNA markers and allozymes showed that the genetic structure of natural populations presents two characteristics: excessive homozygosity and subdivision. Advances of various breeding techniques, including introduction, selection, hybridization, polyploidy, gynogenesis and gene manipulation, were reviewed in the other part. Although Haliotis discus discus, introduced from Japan, has become one of the most important culture species in China, the economic, social and environmental effects of introduction have been rarely studied. Select ion is one of the most important and basic breeding techniques, but the studies on selection are only a few and preliminary, referring to the relations between genetic characteristics and the traits of growth and resistance, genetic diversity and heritability of quantitative traits, and the effect of selection. Interspecific hybridization was the first breeding program carried out in abalone. Experimental hybridization have been carried out for about 20 crosses. Heterosis, such as faster growth and high survival rate, has been observed in some crosses. Triplo ids have been successfully induced in many species of abalone with physical or chemical shock, e. g. H . discus hannai , H . ruf escens , H . diversicolor diversicolor and H . midae. Field experiments were conducted in some species of triploid abalone. In comparison with triploid, the research on tetraploid is still in quest stage. The progress of induction of gynogenesis in abalone is quite slow. Conditions of sperm inactivation, diploid restoration and nuclear behavior of gynogenetically activated eggs have been researched on in H . discus hannai . Notwithstanding the gene transfer techno logy in abalone is in the quest stage, the research have already involved preparation of exogenic DNA, means of gene transfer, identif icat ion integration and expression of target gene, etc. Three research directions in these topics were proposed: to investigate the germplasm resources of abalone deeply and widely, to make use of traditional breeding methods and modern biotechnique synthetically, and to combine the science research with production practice.

摘要:Shrimp farming is an important source of revenue and employment in many developing countries . However,infectious diseases have adversely affected the profitability of shrimp industry. For this reason,disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper ,the current importance and problems of shrimp2culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters , they are composed of haemocyte count (THC) , differential haemocytecount (DHC) and reactive oxygen intermediates (ROIs ). The immunity cells exert their defence functions through phagocytizing , enveloping , etc ,and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters , prophenoloxidase (ProPO) and phenoloxidase , antimicrobial peptides and proteins , hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria , virus , etc. and environmental factors such as DO , pH, etc , were also reviewed. It is well2known that the immune responses induced by immunizing crustacean or shrimp are mainly the non2specific immune responses. The potential of immunological parameters , including the changes of THC and DHC , the production of ROIs , phenoloxidase (PO) activity , antibacterial activity of plasma , and so on , to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed.

摘要:大眼金枪鱼(Thunnus obesus)是延绳钓渔业的目标鱼种.大西洋金枪鱼国际保护委员会(ICCAT)对于大西洋大部分金枪鱼鱼种的生物学特性、资源状况、分布[1-8]、主要鱼种分布的适宜水温等[9,10]进行了广泛的研究,而国内还未曾有过这方面的报道.本文根据科技部863计划大西洋金枪鱼渔场生产调查项目和我国政府第一次向大西洋公海金枪鱼渔业派遣科学观察员项目的要求,按照国际渔业组织技术规范测定了大眼金枪鱼的生物学数据,对其性腺成熟度、摄食等级、摄食种类、性比、渔获物的叉长分布、叉长与净重(去腮、去内脏、去鳍、去部分腮盖-DWT)的关系、叉长与体重的关系、体重与净重的关系等生物学特性进行初步分析,有利于进一步研究大眼金枪鱼的生物学特性、资源状况、对其资源量进行较为准确的评估,为确定配额、资源的养护和管理提供科学依据.

摘要:In this paper, the effect s of methmidophos and phoxim with different concentrations and schedule on soluble protein content and chlorophyl a ( Chla) content in Porphyra haintanensis were studied under experimental and ecological conditions. The result s showed as follows: ( 1) there were some time-ef fect and dose-effect relationships between the pollutants and Chla contents. The Chla content of most of groups decreased with the increasing of do se and prolonging of the exposure time. In the same concentration, the toxicities of phoxim to Chla content was stronger than that of methmidophos. ( 2) All concentration groups in this study didn. t show the signif icant time-ef fect and dose-effect relationships between pollutants and the soluble protein. And there was no signif icant difference of the soluble protein content among various groups.