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武汉单极虫生活史中放射孢子虫的发现及鉴定 总被引：1，自引：1，他引：0
鲫养殖中粘孢子虫病非常严重,为掌握其病原的感染传播途径,实验通过粘孢子虫生活调查研究,在底栖寡毛类苏氏尾鳃蚓体内发现了一种放射孢子虫。该放射孢子虫的孢子无孢柄;孢体顶面观和侧面观都呈近卵圆形,长(19.8±1.3)μm,宽(18.2±1.1)μm;3个极囊梨形,呈点状聚集分布在孢体顶端,极囊长(4.53±0.4)μm,宽(3.4±0.4)μm;3个尾柄几乎等长,刺状,从孢体基部向下伸展,尾柄间夹角100°,尾柄长(195.0±15.7)μm,宽(11.5±0.8)μm。根据形态特征将其划归为橘瓣放射孢子虫集合类群。18S r DNA序列分析表明该放射孢子虫与鲫体表寄生武汉单极虫为同一物种,序列相似率为99.8%~100%。序列系统发育分析进一步发现单极虫类群中多数种类的放射孢子虫阶段主要寄生在苏氏尾鳃蚓体内。本研究首次发现和报道了鲫寄生武汉单极虫生活史中寡毛类宿主及其放射孢子虫的形态特征,为鲫粘孢子虫病生态防控提供重要的基础资料。 相似文献
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引起池养异育银鲫高死亡率的粘孢子虫新种咽碘泡虫形态和分子分析 总被引：1，自引：0，他引：1
对近几年发生在江苏省盐城地区引起池养异育银鲫大批死亡的粘孢子虫进行了形态和分子等方面分析研究,发现该粘孢子虫主要特点是:孢子梨形,部分孢子后部外周包围有透明无色的膜状鞘和壳瓣底部内侧呈现1～6个"V"形缺刻,两个极囊大小不等,孢子前端内侧两个极囊间有一个细长的囊间突起,胚质中无嗜碘泡,孢囊大小10～25 mm,孢子长16.82±0.43(16.03～17.69)μm,孢子宽10.26±0.43(9.12～10.88)μm,孢子厚8.09±0.29(7.50～8.75)μm,孢子长宽比1.64±0.09(1.50～1.93);大极囊长8.66±0.25(8.25～9.16)μm、宽3.65±0.25(3.01～4.19)μm,小极囊长8.35±0.28(7.60～8.85)μm、宽3.58±0.23(3.09～4.11)μm,囊间突起长1.80±0.12(1.59～2.00)μm。特异性地寄生在异育银鲫的口咽腔上颚的咽组织内、具有寄主和寄生在咽部的专一性,PCR扩增得到1 576 bp的18S rDNA序列,GenBank登录号为JQ726700。该粘孢子虫与相近的其它粘孢子虫比较,孢子长分别与白鲟碘泡虫(Myxobolus psephurusi)和扭曲碘泡虫(M.twistus)无显著差异(P>0.05),与M.ampullicapsulatus、M.wulii和鳙碘泡虫(M.aristichthydis)分别有显著差异(P<0.05);孢子宽和厚、极囊长和宽分别与M.ampullicapsulatus、M.wulii、白鲟碘孢虫(M.psephurusi)、鳙碘泡虫(M.twistus)和扭曲碘孢虫(M.aristichthydis)有显著差异(P<0.05);分子系统树分析结果显示,与M.ampullicapsulatus在同一个分支中,亲缘关系最近。从孢子形态学、寄主的特异性、寄生部位的专一性以及18SrDNA序列等特点综合比较分析,表明该粘孢子虫为一新种,命名为咽碘泡虫Myxobolus pharynae n.sp.。 相似文献
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为有效鉴定三棱碘泡虫的有效性,补充其生物学特征,实验利用现代粘孢子虫整合分类学方法,包括形态特征、寄生特性(宿主特征和寄生部位)及分子特征,对其进行重新描述,证实其分类有效性,探讨其系统发育关系。结果显示,三棱碘泡虫专性寄生于草鱼鳃丝间,未在其他器官(肝脏、肾脏、肠道等)检获孢子。包囊呈乳白色,长椭圆形,长(2.4±0.3)(2.1～2.7) mm,宽(0.8±0.1)(0.6～0.9) mm。成熟孢子壳面观呈卵圆形,孢子后端未见"V"形褶皱,孢子外包裹有一层透明的圆形黏液膜,缝面观呈纺锤形,孢子缝面可见三条平行而突出的脊线;孢质均匀,孢子后端具有一个大嗜碘泡;成熟孢子长(10.3±0.4)(9.4～11.0)μm,宽(9.5±0.5)(8.7～10.9)μm,厚(7.4±0.5)(6.4～8.0)μm;两极囊等大,梨形,极丝7～8圈;组织病理显示,病灶鳃组织未出现严重炎症反应。BLAST比对发现,三棱碘泡虫与隐杆碘泡虫小核糖体RNA序列相似性最高(89.58%),但远低于种内序列相似性。分子系统发育分析结果显示,三棱碘泡虫先与寄生于鲤科鱼类的隐杆碘泡虫形成姊妹关系,再与寄生于胭脂鱼科鱼类鳃的诺布尔碘泡虫、微小碘泡虫及毕斯塔斯碘泡虫形成独立的鳃寄生碘泡虫分枝,表明宿主亲缘关系与组织趋向性在鱼类组织寄生碘泡科粘孢子虫系统演化历程中扮演重要作用。本研究补充了三棱碘泡虫包囊形态结构、组织趋向性及分子数据,证实了其分类有效性。 相似文献
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相同室外网箱养殖条件下,比较白鲫自交F_1及其与散鳞镜鲤、黑龙江野鲤、禾花鲤和兴国红鲤四种鲤鱼杂交F_1鱼苗的形态特征与生长的差异。结果显示:全长/体长、体长/体高、体长/头长、头长/头高等可量性状参数比值差异显著,可作为几者之间形态区别主要参数。其中白鲫(♀)×黑龙江野鲤(♂)的全长为体长的1.64倍,体长为体高的3.00倍,为头长的3.50倍,为尾柄宽的7.68倍,尾柄长为尾柄宽的1.48倍。各方面指标显著优于其他组别。从数据可以看出白鲫(♀)×黑龙江野鲤(♂)体略高,头略短,尾柄略窄长,体型较修长,表明该杂交组合鲫鱼体长体重增长率方面都显著优于其他组合,体型合适。 相似文献
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选取93尾(♂31尾,♀62尾)体质量(200±49)g淇河鲫鱼成鱼,选择鱼体形态特征的14个变量观察其外部形态的两性异形。采用协方差分析、因子分析和多元判别分析研究不同因变量的性差大小。14个变量中有7个变量(体高、体宽、头长、吻长、眼径、眼后长和尾柄长)在性别之间存在显著差异(P0.05或0.01)。以体长为协变量对13个形态特征变量进行因子分析发现,第一因子的特征值为4.117,主要变量为全长、体高、尾柄长和尾柄高,解释总方差的31.7%;第二因子的特征值为2.721,主要变量为头长、吻长和眼径,解释了总方差的20.9%;第三因子的特征值为2.594,主要变量为胸鳍长、腹鳍长和臀鳍长,解释了总方差的19.9%,3个因子共解释总方差的72.5%。判别分析的总体正确判别率为80.4%~86.3%,交互检验比回代检验的性别正确判别率略低一些,为76.5%~78.4%。结果显示雌性个体体长大于雄性个体,雄性尾柄长和尾柄高大于雌性,外部体型变量(体高、体宽和尾柄长)具有显著的两性异形。 相似文献
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斜带石斑鱼形态性状与体质量的相关性和通径分析 总被引：1，自引：0，他引：1
对4月龄斜带石斑鱼体质量、头长、躯干长、体长、全长、体高、体宽、眼间距、眼径、吻长、尾柄高和尾柄长等12个性状的测量数据进行了多元分析,以明确斜带石斑鱼形态性状与体质量的相互关系。结果显示,斜带石斑鱼的各形态性状间相互关系达极显著水平(P0.01);通径分析结果表明,全长(x_4)、体高(x_5)、眼间距(x_7)、眼径(x_8)和尾柄高(x_(10))对体质量的通径系数达极显著水平(P0.01),其中全长的直接影响最大,而体高、眼间距、眼径和尾柄高主要通过全长间接影响体质量;这5个性状对体质量的共同决定系数之和为0.920,说明全长、体高、眼间距、眼径和尾柄高是影响4月龄斜带石斑鱼体质量的主要性状;回归分析建立了4月龄斜带石斑鱼形态性状与体质量的回归方程。本研究可为斜带石斑鱼的选择育种提供参考。 相似文献
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随机选取10月龄深水抗风浪网箱养殖的点篮子鱼183尾,体质量14.8～199.4g,体长8.0～18.7cm,采用灰色关联分析方法对全长、体长、体宽、体高、眼径、吻长、眼后头长、头长、头高、尾柄高、尾柄长等11个形态性状与体质量的关联度进行了分析和评价。研究结果显示,网箱养殖点篮子鱼的形态性状与体质量的关联度为0.3962～0.9702,其中,与体质量关联度最高的前3个形态性状为体长、全长和体高,关联度分别为0.9702、0.9693、0.9668,其余形态性状与体质量的关联度依次为全长>体高>体宽>吻长>尾柄长>尾柄高>头高>眼后头长>头长>眼径。综上,宜将体长、全长和体高选为间接选育点篮子鱼体质量的形态指标,本研究将为点篮子鱼群体选育提供理论依据和分析方法。 相似文献
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夹江花(鱼骨)的形态生物学 总被引：3，自引：0，他引：3
测量分析了夹江花(鱼骨)的外部形态特征和框架特征,为其形态种质标准和系统分类研究提供参考.可数性状方面:背鳍Ⅲ-7,尾鳍19,臀鳍Ⅲ-6,腹鳍I-8,胸鳍I-16～19,第一鳃弓鳃耙数6～10,围尾柄鳞18～20,侧线鳞46(6.5-7.5)/(4.5-V)49,下咽齿3行、1.3.5-5.3.1,脊椎骨4 42～44;可量性状方面:全长为体长的1.20倍,体长为体高4.38倍、为头长4.18倍、为尾柄长5.52倍、为肠长0.84倍,头长为吻长2.79倍、为眼径4.21倍、为眼间距3.47倍,体高为体宽1.50倍,尾柄长为尾柄高1.77倍.体重与体长相关式为W=0.0123L3.083,n=30,r=0.9983.肥满度系数为1.57. 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献