共查询到20条相似文献，搜索用时 203 毫秒
1.
头足类角质颚的研究进展 总被引：13，自引：1，他引：12
随着世界传统经济渔业资源的衰退,头足类资源的开发和利用得到各国的普遍重视,对其资源状况、生物学等方面的研究得到不断地开展。角质颚是头足类的主要捕食器官和硬质组织之一,具有结构稳定、耐腐蚀、储存信息良好等特点,可作为分类和生物学研究等的重要材料。本文根据国内外学者对其研究的成果,系统描述了角质颚的形态特征,对其在头足类生物学和分类地位、资源量估算、捕食动物的食性分析等方面的应用研究做了综述。分析认为,尽管角质颚在头足类研究中已取得一定的进展,但其在年龄鉴定和资源评估等方面还面临着一些问题,需要在以后的研究过程中加以解决。 相似文献
2.
线粒体DNA标记在头足纲动物分子系统学中的应用 总被引：1，自引：1，他引：0
动物线粒体DNA(mtDNA)基因组具有在细胞中大量存在、缺少重组、多为母系遗传、缺少内含子以及进化速率高等特点,广泛应用于比较和进化基因组、分子进化、种群遗传、物种鉴定和不同分类水平上的系统发生学研究。头足类作为软体动物门中的重要经济种类,其分类和系统进化研究历来是热点领域。本文主要对头足类动物mtDNA组成与特点(包括基因组成、重排等)、常用mtDNA标记对其不同分类阶元的适用性以及线粒体基因片段和全基因组在头足类系统演化中的作用进行了阐述,并对未来发展进行展望。 相似文献
3.
中国近海头足类基础生物学研究进展 总被引：1，自引：0，他引：1
《海洋渔业》2017,(6)
本论文对中国近海头足类基础生物学的研究进展进行了回顾,重点对种类组成及地理分布、形态学测量及应用、年龄与生长、摄食生态学、发育与繁殖等方面进行了分析。分析认为,头足类组成与分布由北向南逐渐递增,渤海最少,南海最多。形态学测量及应用的研究主要集中在外形特征的描述及利用其进行种类鉴定,其它组织(如耳石和角质颚等硬组织)的研究较少,今后应该利用这些硬组织进行种类鉴别和种群划分。年龄鉴定作为头足类研究的重点之一,是生物学的基础内容,目前主要通过内壳和耳石对十腕目进行年龄与生长的研究。另外,耳石和角质颚等硬组织隐含着重要的生态信息,可利用其进行微量元素、稳定同位素与栖息环境的关系及其生活史过程等的研究。摄食生态主要用于了解头足类的生态地位,对于非养殖种类,主要研究其食物组成、摄食强度及营养级;而对于养殖种类,则可通过喂养研究其生长、成活率和孵化率等。因此,针对不同资源产业的发展阶段,中国近海头足类基础生物学的研究重点不一样,随着近海增殖放流等措施的发展,学者将注意力由头足类的自然群体转向养殖群体,更多的研究内容涉及胚胎发育、受精卵孵化、繁殖生物学、环境因子胁迫等方面。在今后的研究中,应利用乌贼类和蛸类作为实验材料,开展不同海洋环境条件下(包括海洋酸化等),头足类的生长与死亡、生活史等基础渔业生物学的研究,预测其可能产生的影响。综合分析认为,相对其它经济鱼类,近海头足类的基础生物学研究工作较为不足,应加强多学科的合作,系统、有计划地采集近海头足类样本,建立近海头足类的样本库和基础生物学库,为科学开发和利用近海头足类资源提供基础。 相似文献
4.
为了研究大型海洋掠食性鱼类胃含物中角质颚的分类效果,于2017年10月,2018年3、5和11月,收集了南大西洋、中东太平洋和西印度洋海域的大型海洋掠食性鱼类的36个胃并分析其残留角质颚的形态。对采集的角质颚形态侧视图和顶视图进行种类鉴定,建立检索表,提取椭圆傅里叶描述子(EFDs)系数进行聚类分析。结果显示,通过对胃含物角质颚形态进行种类鉴定,共发现头足类2目10科17种。根据角质颚形态分类检索分析,17种头足类角质颚形态种间差异明显。枪形目(Teuthoidea)的13种头足类角质颚喙部形态分别为三角形和等腰三角形,侧壁为近似菱形,翼部发达;八腕目(Octopoda)的4种头足类角质颚有喙部发育,侧壁近似长四边形,有翼部发育。角质颚形态信息聚类分析在目级别区分效果显著。通过对胃含物角质颚形态进行分类研究,不仅可佐证胃含物头足类的识别,而且丰富了胃含物头足类的鉴定内容,也为大型海洋掠食性鱼类胃含物头足类分类鉴定体系奠定基础。 相似文献
5.
头足类是古老而高等的海生软体动物,贝壳是其重要的硬组织之一,可分为外壳和内壳。其中内壳根据质地不同又可分为角质、石灰质和软骨质3种类型,三者在形态和组成成分上差异明显。头足类贝壳不仅是重要的分类性状,而且在生物学、生态学上应用广泛。可利用外壳、石灰质内壳和软骨质内壳的形态特征在属分类水平上进行应用;角质内壳的形态特征在各种间细微结构差异明显,需要不断积累资料和归类分析。角质和石灰质内壳是年龄和生长研究的重要材料,其生长纹的日周期性证实和选择合适角质内壳部位是研究的关键,其日纹形成与水温、食物丰度等因子关系密切。贝壳的形态特征一定程度上反映了头足类的栖息环境,可通过对其同位素含量及其组成分析来揭示栖息地的水温、食物丰度等深层次的生态信息,并已成为目前研究的热点之一。 相似文献
6.
头足类的资源开发和利用已经得到各国的普遍重视,对其基础生物学等方面的研究得到不断的发展。作为头足类的主要捕食器官之一,角质颚这种不靠关节、仅靠肌肉收缩来运动的方式引起了学者们极大的兴趣,同时其固有的形态特点是分类学的良好性状,所包含的大量信息也可以用于生态学方面的研究。本文根据国内外学者对其运动模式的解释,阐述了相关结构的特点,同时对角质颚在头足类分类和生态学等方面的应用研究做了综述。回顾前人的研究发现,对角质颚的功能性研究已有一定的成果,今后的研究应该更加关注对角质颚特征定量整理,并编制检索表,同时根据该结构中的信息,分析头足类在生态系统中的准确定位和相关的环境关系。 相似文献
7.
年龄与生长是渔业基础生物学研究的重要内容。体长频度法估算头足类的年龄并不可靠,而利用硬组织来研究头足类的年龄和生长是最为有效的方法之一。内壳作为头足类少数硬组织之一受到国内外学者的广泛关注。本文从内壳的提取、保存、制备、观察,生长纹的特征,生长纹周期性以及日龄鉴定等方面综述了其在头足类年龄和生长方面的研究进展。分析认为,柔鱼类内壳因其生长早期的生长纹不清晰而无法用来鉴定其整个生活史的年龄;乌贼类内壳因其生长受环境尤其水温的影响显著,因此并不适合用作年龄鉴定的材料;而章鱼类内壳在其年龄和生长研究中应用前景最广泛。今后的研究希望能够在年龄鉴定基础上,开展内壳时间序列上的微量元素与稳定同位素研究,为进一步分析头足类的种群结构、摄食生态、栖息环境以及生活史等内容提供基础资料。 相似文献
8.
头足类角质颚稳定同位素研究进展 总被引：3，自引：0，他引：3
角质颚作为头足类重要硬组织之一,结构稳定、耐腐蚀、易获取,蕴含着大量的生物与生态学信息,在头足类的年龄鉴定、生长估算、种群划分、摄食生态评估、洄游路线推测以及栖息环境重建等方面受到国内外学者的广泛关注。过去,角质颚的研究主要集中在形态与微结构的分析与应用领域。近年来,随着地球微化学手段的不断创新与进步,角质颚的稳定同位素的研究越来越受到海洋生物与生态学家的重视。本文根据国内外学者对其的研究成果,重点对碳氮稳定同位素在头足类摄食生态评估、栖息环境重建和洄游路线推测等方面的应用进行综述,旨在解读头足类不同生活史阶段的生物与生态信息,其应用前景十分广阔。 相似文献
9.
10.
头足类耳石信息分析的研究进展 总被引：1，自引：0，他引：1
耳石的轮纹结构与化学组成相当稳定,记录了个体生活过程中丰富的生物-物理-化学环境信息,是一种很好的信息载体.因此,通过耳石信息分析可以揭示头足类的生活史历程,掌握其生活史各阶段的生态环境特征,这不仅具有重要的理论意义,而且具有较为广阔的应用前景.文章依据近年来国内外有关头足类耳石信息分析的研究成果,综述了头足类耳石日轮及微量化学的研究现状,概括了耳石信息分析在渔业资源及环境科学等方面的应用,并对今后的研究工作提出了方向与内容上的展望. 相似文献
11.
Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
下载免费PDF全文
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
12.
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
13.
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
14.
15.
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
16.
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
17.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
18.
William King V David L. Berlinsky Craig V. Sullivan 《Fish physiology and biochemistry》1995,14(6):489-500
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass. 相似文献
19.
Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide 总被引：1，自引：0，他引：1
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response. 相似文献
20.
Sandra García‐Garrido Ismael Hachero‐Cruzado Carlos Rosas Pedro Domingues 《Aquaculture Research》2013,44(11):1741-1751
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting. 相似文献