中国杉藻科(Gigartinaceae)两个新记录种的研究

报道中国产杉藻科(Gigartinaceae)角叉菜(Chondrus ocellatus)和日本马泽藻(Mazzaella japonica)两个种的分类研究,均为中国新记录。     

Development of the follicle complex and oocyte staging in red drum,sciaenops ocellatus linnaeus, 1776 (perciformes,sciaenidae)

Pelagic egg development in red drum, Sciaenops ocellatus, is described using tiered staging. Based on mitosis and meiosis, there are five periods: Mitosis of Oogonia, Active Meiosis I, Arrested Meiosis I, Active Meiosis II, and Arrested Meiosis II. The Periods are divided into six stages: Mitotic Division of Oogonia, Chromatin Nucleolus, Primary Growth, Secondary Growth, Oocyte Maturation and Ovulation. The Chromatin Nucleolus Stage is divided into four steps: Leptotene, Zygotene, Pachytene, and Early Diplotene. Oocytes in the last step possess one nucleolus, dispersed chromatin with forming lampbrush chromosomes and lack basophilic ooplasm. The Primary Growth Stage, characterized by basophilic ooplasm and absence of yolk in oocytes, is divided into five steps: One‐Nucleolus, Multiple Nucleoli, Perinucleolar, Oil Droplets, and Cortical Alveolar. During primary growth, the Balbiani body develops from nuage, enlarges and disperses throughout the ooplasm as both endoplasmic reticulum and Golgi develop within it. Secondary growth or vitellogenesis has three steps: Early Secondary Growth, Late Secondary Growth and Full‐Grown. The Oocyte Maturation Stage, including ooplasmic and germinal vesicle maturation, has four steps: Eccentric Germinal Vesicle, Germinal Vesicle Migration, Germinal Vesicle Breakdown and Resumption of Meiosis when complete yolk hydration occurs. The period is Arrested Meiosis II. When folliculogenesis is completed, the ovarian follicle, an oocyte and encompassing follicle cells, is surrounded by a basement membrane and developing theca, all forming a follicle complex. After ovulation, a newly defined postovulatory follicle complex remains attached to the germinal epithelium. It is composed of a basement membrane that separates the postovulatory follicle from the postovulatory theca. Arrested Meiosis I encompasses primary and secondary growth (vitellogenesis) and includes most of oocyte maturation until the resumption of meiosis (Active Meiosis II). The last stage, Ovulation, is the emergence of the oocyte from the follicle when it becomes an egg or ovum. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.     

Spermatozoa in triploids of the rosy bitterling Rhodeus ocellatus ocellatus

Artificially induced triploid male Rhodeus ocellatus ocellatus showed typical nuptial colorations, irrespective of spermiation. In milt from triploids, abnormal spermatozoa (malformation of the head and mitochondrion, excessive formation of the head, mitochondrion and flagellum, and no flagellum) occurred at 78°4% frequency. Spermatozoa with multiflagella were most common, often with a saccate-like organ. Many triploid spermatozoa moved actively as long as those of diploids (10·92±0·91 min=mean±S.D., P >0·05), but did not advance like diploids, spinning around until movement ceased. The sperm density in triploids was < 2% of that from diploids. In triploid testes, deformed and variously sized spermatids were often observed, and normal spermatids and spermatozoa were seldom recognized. The DNA content of triploid spermatozoa varied greatly, compared with that of diploids. Peak of sperm DNA content differed slightly between two triploid samples with two peaks at 1·5 n and 1·9 n ( P <0·0001 in both), respectively. Triploids had the greatest average sperm head diameter of 2·25±0·67 μm (mean±S.D.), while that of diploids was 1·83±0·15 μm ( P =0·002). In the fertilization test using the eggs of diploids ( n =1500, 30 trials), only one egg developed. The embryo chromosome number was 60 (2·5 n) and the ploidy of spermatozoa contributing to fertilization appears to be 1·5 n. The extremely low fertility of triploid R. o. ocellatus spermatozoa seems to be caused by the reduced motility and large head size of spermatozoa, and the low sperm density of the milt. The ploidy of spermatozoa that are successful in fertilization is likely to be related to the distribution pattern in the DNA content of cells.     

水流速度对黑鲷和美国红鱼续航游泳能力及生理代谢的影响

为了确保黑鲷(Acanthopagrus schlegeli)和美国红鱼(Sciaenops ocellatus)在开放海域的养殖产量和鱼类养殖福利,在20℃下,对体长差异性不显著(P>0.05)的两种鱼进行续航游泳能力测试。首先,确定不同流速下的耐力游泳时间,然后选择耐力游泳时间为150min时的速度进行续航游泳实验。其中黑鲷和美国红鱼分别被迫以3.15和4.32 BL/s的恒定游泳速度,进行0、30min、60min、90min、120min和150min的测试,解剖鱼获得肌肉、血液和肝脏,测定样品在6个时间点的代谢物浓度,每个时间点保证3组有效数据。对0和150min的实验组对比,结果显示,两种鱼肝糖原、背肌乳酸和血糖浓度差异显著(P<0.05),肌肉糖原浓度差异不显著(P>0.05)。双变量相关分析显示,随着疲劳程度增加,肝糖原浓度下降,背肌乳酸和血糖上升。灰度关联分析和主成分分析显示,血糖和肝糖原浓度是影响疲劳的主要因素,但黑鲷相比美国红鱼,其浓度变化范围更大。综上:(1)美国红鱼比黑鲷拥有更强的游泳能力,而且黑鲷和美国红鱼不适合养殖在流速超过3.15和4....     

Purification and characterization of phenoloxidase from Octopus ocellatus

Phenoloxidase （PO） from ink sacs of Octopus ocellatus was purified by gel-filtration and ion-exchange chromatography, and characterized in terms of its biochemical and enzymatic properties by using L-dihydroxyphenylalanine （L-DOPA） as the specific substrate. It was found that prophenoloxidase from O. ocellatus was isolated as a heterodimeric protein of 153.8 kDa, and two subunits of 75.6 and 73.0 kDa were often detected in preparations after SDS activation. The PO-like activity showed optimal pH of 7.0, optimal temperature of 40℃, and an apparent Km value of 3.1 mM on L-DOPA, and 6.3 mM on catechol, respectively. The PO-like activity was extremely sensitive to 1-phenyl-2-thiourea and sodium suifite, and very sensitive to ascorbic acid, thiourea, citric acid, and benzoic acid. Together with its specific enzyme activity on catechol and L-DOPA, it can be concluded that the Octopus PO is most probably a typical o-diphenoloxidase. The PO-fike activity was also strongly inhibited by Cu^2＋, Zn^2＋, ethylenediaminetetraacetic acid and diethyldithiocarbamate （DETC）, and the DETC-inhibited PO-like activity could be perfectly restored by Cu^2＋. These results indicated that Octopus PO is most probably a copper-containing metalloenzyme. All these results implied that the PO from O. ocellatus has the properties of a catechol-type copper-containing o-diphenoloxidase which functions not only as a catalytic enzyme in melanin production in ink sacs but also as a humoral factor in host defense via melaninization as in other crustaceans.     

美国红鱼生长激素基因的克隆及其遗传进化分析

采用PCR方法从美国红鱼肝脏中扩增出美国红鱼生长激素基因。该基因序列长为1 497 bp,与5个已报道的鲈亚目鱼类生长激素基因结构比较发现,他们的外显子和内含子之比均为6∶5,而且相对应的6个外显子大小一致。用Clustal X软件对美国红鱼和其他13种鲈形目鱼类生长激素基因序列进行比对,选取同源性较高的551 bp的编码区序列构建NJ和MP系统进化树,结果发现由其构建的MP和NJ树与根据形态特征构建的系统发育树基本一致,特别是在鲈形目鱼类科间及科以上分类阶元的系统发育研究方面比较一致。研究结果表明鱼类生长激素基因序列能够较真实反映近缘鱼类之间的关系,是进行鲈形目鱼类系统进化分析的较好遗传标志。     

久效磷对美国红鱼鳃Na^＋／K^＋-ATP酶活性和超显微结构的影响

经不同试验浓度的久效磷(0．25、0．5、1．0和2．0mg·L^-1)处理美国红鱼4d后,分别对鱼鳃Na^+／K^+—ATP酶活性和氯细胞密度进行了测定和计数,并观察了鱼鳃组织显微结构和超微结构的变化。结果表明,低浓度久效磷(0．25mg·L^-1)处理可以诱导鱼鳃氯细胞大量增生,Na^+／K^+—ATP酶活性增强,随着试验浓度的增加,久效磷对鳃组织的损伤越来越重,Na^+／K^+—ATP酶活性逐渐降低;久效磷对鱼鳃显微结构的损伤表现为鳃小片上皮细胞水肿、脱离。鳃小片基部粘连。鳃小片上皮细胞角质化;超微结构变化主要为内质网、线粒体、微小管和核膜的水肿及部分溶解,这种损伤表现为由细胞膜到细胞核的动态过程。     

Ownership influences the outcome of male-male contests in the scincid lizard, Niveoscincus microlepidotus

Male snow skinks (Niveoscincus microlepidotus) in the Tasmanian highlands have broadly overlapping home ranges, and fight vigorously(often with substantial damage to one or both participants)upon encountering another adult male. We observed 32 male-malecontests, involving at least 49 different males, during a five-yearfield study near the summit of Mount Wellington. Bouts involvingsimilar-sized lizards typically continued for longer than boutsinvolving a greater size disparity between the combatants. Resident males won 72% of all bouts, despite a lack of any significantdifference between residents and intruders in body sizes, relativehead sizes or body condition. Thus, prior residency of a siteappears to be the major determinant of success in male-malerivalry.     

Locomotor impairment of gravid lizards: is the burden physical or physiological?

Pregnancy is associated with reduced locomotor performance in several reptile species, but the reasons for this reduction remain unclear. Previous authors generally have assumed that the decreased maternal mobility is due to the physical burden of the clutch, but our data on a viviparous Tasmanian scincid lizard (Niveoscincus microlepidotum) suggest a different interpretation. Running speeds of gravid female skinks decrease during gestation (as litter mass increases), but this locomotor impairment is due to physiological changes associated with pregnancy, rather than simple physical burdening. Maternal running speeds are unrelated to litter masses, and do not increase in the week after parturition. Females with very large abdominal fat‐bodies (due to ad libitum feeding in the laboratory), equivalent in mass to the litter, nonetheless run rapidly. If the locomotor ‘costs’ of reproduction reflect all‐or‐none physiological changes associated with pregnancy, then the magnitude of such costs may correlate only weakly with the actual level of reproductive investment. Because life‐history models predict that the relationship between fecundity and ‘cost’ has important evolutionary consequences, our results highlight the need to clarify the causal basis for locomotor impairment in gravid reptiles.     

饵料中不同脂肪水平诱导红姑鱼脂肪肝病的研究

1260尾初始重约为273g的红姑鱼(Sciaenopsocellatus)分为9组,每组3个平行,用9种不同水平蛋白质与脂肪日粮饲养于循环水系统的水泥池网箱内,在水温为232±20℃条件下养殖56d。本实验为饵料中不同脂肪水平诱导红姑鱼脂肪肝病的研究。9种日粮中蛋白质含量分别为:36%,40%,44%;脂肪含量分别为:4%,8%,12%。红姑鱼的各期生长率和存活率随着日粮脂肪含量增加而显著下降,红姑鱼肝胰脏脂肪含量与日粮脂肪水平成正比,各组红姑鱼均发生程度不同的营养性脂肪肝病,其病变程度与日粮脂肪水平成正相关。饲喂脂肪含量分别为8%,12%日粮的红姑鱼从实验3周起开始大量发病死亡,死亡率在5周达到高峰。主要表现为厌食,不游动,皮肤发黑,消瘦直至死亡。解剖见肝胰脏肿大,苍白发黄,柔软易碎。组织学检查发现,各组红姑鱼肝胰脏均见肝细胞不同程度的脂肪变性,溶解坏死,胰腺细胞亦萎缩。电子显微镜观察,在肝细胞线粒体、内质网与细胞浆内有大量微细至大颗粒状的脂滴出现。实验结果表明,饲喂9种不同水平的蛋白质和脂肪日粮的红姑鱼均引起营养性脂肪肝病,其病变程度与日粮脂肪水平成正相关,日粮中脂肪是红姑鱼发病与死亡的直接原因。