天然三倍体鲫鱼突变体萍乡肉红鲫线粒体细胞色素b基因序列分析

用细胞色素b(Cyt b)基因特异性引物,对萍乡肉红鲫(Carassius auratus var.pingxiangnensis)的线粒体Cytb基因进行PCR扩增和双向测序。在12个个体中均得到序列一致的Cytb基因全序列,长度为1 140 bp。其A、T、G、C含量分别为28.2%(321)、28.8%(328)、14.8%(170)和28.2%(321),A+T含量(57%)明显高于G+C含量(43%),与其他水生动物相同基因片段碱基含量相似。该基因中密码子第1位核苷酸中4种碱基组成较为均衡;第2

我国华鳊属鱼类形态差异及其物种有效性的研究

为探讨华鳊属鱼类种间和种内居群间的形态差异及其物种有效性 ,采用多变量形态度量 ,结合传统分类方法 ,获得该属鱼类不同地理居群共 2 2 4尾标本的 32个测量性状和 7个可数性状数据 ,并做主成分分析。在可数性状上 ,海南华鳊各居群间无差异 ,但明显不同于其他种类 ;四川华鳊与大眼华鳊差别明显 ,与伍氏华鳊之间也存在较大程度的差异 ;大眼华鳊的乌江和珠江居群之间存在显著差异 ,而伍氏华鳊各地理居群差异不明显。在可量性状上 ,四川华鳊和大眼华鳊的乌江居群都明显区别于其他种或居群 ,而大眼华鳊的珠江居群与伍

鲤和团头鲂幼鱼卵黄蛋白原的诱导、纯化及电泳比较

采用腹腔注射人工雌激素 1 7α 乙炔基雌二醇 (1 7α ethinyloestradiol,EE2 )的方法 ,在鲤幼鱼和团头鲂幼鱼体内诱导生成卵黄蛋白原 ;并结合利用阴离子交换介质DEAE SephraroseCL 6B和液相层析技术分离纯化了诱导后的鲤幼鱼和团头鲂幼鱼血浆中的卵黄蛋白原 ;SDS PAGE电泳结果表明所分离的两种鲤科鱼类卵黄蛋白原其亚基的分子量分别为 1 70KD和1 5 0KD。

长江洞庭湖口原生动物的生态学研究

对长江洞庭湖口原生动物群落为期三年的研究结果：种类组成、季节分布、优势种类、丰度的季节变化等，同时还依据食性分析了各种类的功能营养类群，并对河流中原生动物的来源、长江中上游地区原生动物种类组成规律、原生动物功能营养类群和优势种类在河流污染监测中的指示作用等进行了讨论。

中国缨鱼属鱼类的分类整理及一新属描述(鲤形目:鲤科)

经整理我国缨鱼属鱼类仅有1种Crossocheilusreticulatus（Fowler）；原置于此属的种CrossocheilusbamaensisFang和CrosscheilusliuchengensisLiang则归并于另一新属拟缨鱼鹰Pseudocrossocheilusgen．nov，其上唇消失，吻皮与下唇相连，上颌与下唇相连以及口角须发达等特征与缨鱼属不同；同时其口角须发达、下唇两侧有纵行的额沟以及下唇前缘具有显著的乳实状角质突起等特征与直口鲮属Rectoris相异。

中国新记录──小金色藻在武汉东湖的季节消长

一种未曾在中国报道过的小金色藻（ＣｈｒｙｓｏｃｈｒｏｍｕｌｉｎａｐａｒｖａＬａｃｋｅｙ）在武汉东湖发现，此种在冬季出现，春末消失，高的种群密度（８３５７．６ｃｅｌｌｓ／ｍｌ及８７３７．０ｃｅｌｌｓ／ｍｌ）分别在１９９１年２月及１９９２年１月在水温为６─８℃时形成，持续时间近１个月，小金色藻的生物量在东湖营养状况不同的三个采集站是不同的，但季节消长的趋势基本上一致。此种喜生长在富营养的水体中。

卤虫无节幼体和日本绒螯蟹合浦亚种蚤状幼体的冷冻保存

本文研究了葡萄糖、蔗糖和甘油三种冷冻保护剂在不同浓度下对卤虫无节幼体的冷冻保护作用。研究表明用２０％甘油进行保护，无节幼体在－３０℃下耐受９－１０分钟，存活率高达８６．４％，对照组冷冻至－３０℃则全部死亡。本文还研究了浓度为２０％的甘油、ＤＭＳＯ和甲醇对日本绒螯蟹合浦亚种　状幼体的冷冻保护作用，结果表明用２０％甲醇保护的蚤状幼体当冷冻至－２４℃时存活率仍有７５．３％。

草鱼免疫应答的初步研究

研究了草鱼在不同水温条件下受抗原刺激后其中和抗体的变化。15℃培养条件下中和抗体上升缓慢,9周内滴度低于1:8;20℃时,3周后抗体可上升到1:256,最高达1:5270,而在25℃时,1周中和抗体即达到1:570,最高可达1:20000以上。并探索了从草鱼血清中提纯抗体的条件,研究其抗体的特性。草鱼血清中的抗体为大分子蛋白,容易解离为抗原性相同,分子量近似于人IgG的较小分子,含有较多的二硫键,具有类似IgM的某些特性。

武汉东湖针簇多肢轮虫的种群变动和生产量

针簇多肢轮虫(Polyarthra trigla)是武汉东湖的优势轮虫,1983,5—1984,4在Ⅰ,Ⅱ站分别测定了这种轮虫卵和种群密度。Ⅰ站卵的密度在0—245个/升之间,平均为27个/升,种群密度为0—6600个/升,平均为362个/升;Ⅱ站卵的密度为0—321个/升,平均为22个/升,种群密度为0—2770个/升,平均为159个/升。在5—30℃的培养温度下,卵的发育时间随温度升高而缩短,它们间的关系可用下列回归方程表示: lnD=0.4627+1.2929lnT-0.4995(lnT)~2 用直

草鱼出血病病原的研究

草鱼出血病是草鱼种的一种严重疾病,通常在水温25-30℃时发病,其症状表现为全身性组织器官充血。其病原悬液能通过赛氏滤器(Seitz,EKS石棉滤板),能在草鱼种体内及草鱼鳍单层细胞中传代繁殖,在草鱼肌肉单层细胞和性腺单层细胞中感染并出现细胞病变。病原悬液对脂溶剂乙醚敏感,耐热性强,对四环素类药物不敏感。试验结果,我们认为草鱼出血病的病原是病毒。

武昌东湖的数种介形类甲壳动物

<正> 介形类是底栖的切甲类甲壳动物,部分种类的触角上具有发达的游泳刚毛,所以在通常采到的浮游生物标本中亦很常见。早在1903年,G.O.Sars 氏曾经报导过采自我国的介形类共三属五新种。1923年,V.Brehm 也报导过采自我国广州、北京、四川等地的数种介形类,其中还有一新属,三新种及一新变种。

Temporal Coherence of Chlorophyll a during a Spring Phytoplankton Bloom in Xiangxi Bay of Three-Gorges Reservoir, China

Algal bloom phenomenon was defined as "the rapid growth of one or more phytoplankton species which leads to a rapid increase in the biomass of phytoplankton", yet most estimates of temporal coherence are based on yearly or monthly sampling frequencies and little is known of how synchrony varies among phytoplankton or of the causes of temporal coherence during spring algal bloom. In this study, data of chlorophyll a and related environmental parameters were weekly gathered at 15 sampling sites in Xiangxi Bay of Three-Gorges Reservoir (TGR, China) to evaluate patterns of temporal coherence for phytoplankton during spring bloom and test if spatial heterogeneity of nutrient and inorganic suspended particles within a single ecosystem influences synchrony of spring phytoplankton dynamics. There is a clear spatial and temporal variation in chlorophyll a across Xiangxi Bay. The degree of temporal coherence for chlorophyll a between pairs of sites located in Xiangxi Bay ranged from -0.367 to 0.952 with mean and median values of 0.349 and 0.321, respectively. Low levels of temporal coherence were often detected among the three stretches of the bay (Down reach, middle reach and upper reach), while high levels of temporal coherence were often found within the same reach of the bay. The relative difference of DIN between pair sites was the strong predictor of temporal coherence for chlorophyll a in down and middle reach of the bay, while the relative difference in Anorganic Suspended Solids was the important factor regulating temporal coherence in middle and upper reach. Contrary to many studies, these results illustrate that, in a small geographic area (a single reservoir bay of approximately 25 km), spatial heterogeneity influence synchrony of phytoplankton dynamics during spring bloom and local processes may override the effects of regional processes or dispersal.

A redescription of Piguetiella denticulata Liang and, Xie (Oligochaeta, Tubificidae, Naidinae) from China, with a key to the genus Piguetiella

Piguetiella denticulata Liang & Xie, 1997 is redescribed based on the type series collected from the type locality, Songtao River, and streams of the Zhangjiajie Mountain in southwestern China, and specimens from several tributaries of the Yangtze River. This species is characterized by a large body size, the absence of eyespots and dorsal hair chaetae, the same size and shape of dorsal and ventral chaetae, the presence of 3-4 intermediate teeth on both ventral and dorsal chaetae, and an intestinal dilation in IX-X segments. The essential characteristics used to diagnose the genus are discussed and a key to the genus is provided.

Microsatellite diversity and population genetic structure of redfin culter (Culter erythropterus) in fragmented lakes of the Yangtze River

Redfin culter (Culter erythropterus) is a small lethic freshwater fish and widely distributed in the adjacent lakes of the Yangtze River of China. Five microsatellite loci were applied to investigate the genetic variation and population structure of redfin culter from seven lakes in the middle-and-lower reaches of the Yangtze River. The gene diversity was high among the populations (H > 0.9), the average number of alleles among seven populations was low with a range from 2.00 to 3.87. The mean observed (H-O) and expected (H-E) heterozygosity ranged from 0.111 to 0.419 and from 0.162 to 0.750, respectively. Significant deviations from Hardy-Weinberg Equilibrium expectation were found in 50% of the total locus-population combination tests in which heterozygote deficits were apparent. The analysis of molecular variance (AMOVA) indicated that the percentage of variance among and within these populations were 6.18 and 93.82, respectively. The Fst values (0.062, P < 0.001) among studied populations indicated that there were significant genetic differentiations among redfin culture populations from the scattered lakes with different connections to the Yangtze River. These results are useful for the evaluation and conservation of small freshwater fishes. The factors that may be involved in low intra-population polymorphism and the pattern of the population genetic structure of redfin culter from the Yangtze River were discussed.