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1.
本文综述了热应激对鱼类生命活动的影响,包括代谢与生长、抗氧化能力、热休克蛋白以及免疫相关研究成果。鱼受到热应激时,机体会产生对自身有害的活性氧,在一定的温度范围内,鱼类通过酶联通路和非酶联通路来消除体内多余的活性氧。大多水鱼类在适宜温度内,生长率与水温成正相关,超过适宜温度,鱼类代谢紊乱,生长缓慢甚至停止,长时间的热应激会导致鱼类死亡。研究鱼类的耐高温性,对创造更高的水产养殖经济效益和选育耐高温品种具有重要的理论价值和现实意义。  相似文献   

2.
研究水温对鱼类生长影响,阐明最适生长温度及其机制,具有重大理论和实践意义。在鱼类的能量收支中,摄食是唯一的能量收入部分,在影响鱼类摄食量的诸多因子中温度和体重是最重要的两个。本试验设T=20℃、24℃、28℃、32℃四个温度梯度组,分两期进行:Ⅰ期研究在这四个不同温度下红鳍东方鲀幼鱼体重增长和全长增长的情况,Ⅱ期研究在这四个不同温度下不同体重红鳍东方鲀幼鱼对最大摄食量的影响。结果发现在Ⅰ期中当水温T=28℃时红鳍东方鲀幼鱼体重增长和全长增长最快,日增重率和日增长率分别为1.684,0.588。在T=20℃和T=24℃时体重和全长的增长率随温度的升高而逐渐增大,超过28℃时开始降低。在Ⅱ期试验中发现红鳍东方鲀幼鱼最大摄食量随体重的增大而增加,最大摄食量随温度的变化情况为:在试验水温为20~28℃范围内,二者呈正相关,超过28℃度时呈负相关。综合两期试验研究得出28~29℃是适合红鳍东方鲀幼鱼生长的最适温度。  相似文献   

3.
高白鲑属冷水性鱼类,但温度的适应范围较广,可生活在1℃~28℃的水温条件下,其最适温度为15℃~25℃,属滤食性鱼类,主要摄食浮游动物,也摄食部分底栖生物,在冬季冰下可正常摄食生长,对溶氧、酸碱度、盐度有较广的适应,在水域中与其它鱼类饵料竞争程度较低,生长快;肉质鲜嫩味美,营养丰富,具有较高的经济价值,是各产地的重要增殖性鱼类之一。  相似文献   

4.
点篮子鱼幼鱼的热耐受特征   总被引:2,自引:0,他引:2  
为研究驯化温度对点篮子鱼(Siganus guttatus)幼鱼热耐受特征的影响,实验设置了5组驯化水温(19℃、22℃、25℃、28℃和31℃),采用临界温度法对点篮子鱼幼鱼[(2.163±0.450)g]进行研究。结果显示:各驯化温度下(19℃、22℃、25℃、28℃和31℃)的最大临界温度(CTmax)和最小临界温度(CTmin)分别为37.26℃、37.72℃、39.49℃、39.75℃、39.90℃和13.11℃、13.14℃、14.22℃、14.29℃、17.28℃;最大致死温度(LTmax)和最小致死温度(LTmin)分别为37.76℃、38.18℃、39.88℃、40.79℃、40.93℃和11.69℃、11.75℃、11.85℃、12.41℃、15.39℃。点篮子鱼幼鱼在19℃、22℃、25℃、28℃和31℃驯化温度下的温度耐受幅分别为24.15℃、24.58℃、25.27℃、25.46℃、22.62℃;高温驯化反应率最大值出现在22~25℃区间内,为0.663;低温驯化反应率最大值出现在31~28℃区间内,为0.997。19~31℃驯化区间内的热耐受区域面积为296.085℃2。研究结果表明,随着驯化温度的升高,最大临界温度和最大致死温度逐渐增大;随驯化温度的降低,最小临界温度和最小致死温度逐渐减小。点篮子鱼幼鱼的热耐受性明显受到驯化温度的影响。  相似文献   

5.
采用不同的热休克温度处理金鱼受精卵,观察热休克处理对金鱼胚胎发育的影响。结果表明,较高温度的热休克处理能加快金鱼胚胎发育的速度,但过高的温度处理对金鱼胚胎有伤害或致死作用。金鱼较适宜的热休克处理温度为35℃。  相似文献   

6.
秦山核电温排水对鱼类分布的影响   总被引:1,自引:0,他引:1  
根据2010年5月(春季)、2010年9月(夏季)和2009年12月(冬季)秦山核电海域渔业资源调查资料以及秦山核电站温排水扩散数学模拟结果,通过秦山核电温排水海域鱼类季节密度的时空分布、优势种、优势种对鱼类总数量的贡献,探讨并分析了秦山核电海域温排水对鱼类分布的影响。结果显示,春季、夏季和冬季的尾数密度分别为5.55×10~3 ind/km~2、22.10×10~3 ind/km~2和10.52×10~3 ind/km~2,重量密度分别为33.80 kg/km~2、59.06 kg/km~2和66.46 kg/km~2。秦山核电海域渔业资源数量季节变化的规律与其他海域相反,冬季最高,春夏季较低,主要与冬季温排水海域具有暖池效应,形成部分鱼类滞留在此越冬有关。温排水平面分布对鱼类分布有重要的影响。主要表现在夏季温排水区域鱼类密度低于其他水域,冬季相反,鱼群滞留在温排水热羽区域,因而显示出温排水海域有较高的鱼群密度。温排水对不同适温习性鱼类影响不同,暖温种能够适应一定的低温,例如,刀鲚(Coilia ectenes)可以在温排水水域越冬,而对高温有耐受性的棘头梅童鱼(Collichthys lucidus)夏季在温排水水域成为优势种。鱼类优势种的适温性决定着鱼群的分布特征,冬季最重要的优势种为刀鲚,在尾数上的贡献率高达45.02,由于该种在温排水的热羽区域分布密集,形成温排水水域鱼群密度大于周边水域的现象。由于温排水改变了渔场环境,导致新的越冬场的形成,有可能形成新的渔汛,引起当地渔场属性的改变。  相似文献   

7.
温度对真鲷能量收支的影响   总被引:7,自引:0,他引:7  
真鲷系浅海暖温性底层肉食性鱼类,在中国浅海底层鱼类中有着较为广泛的代表性。本研究在以玉筋鱼为饵料生物和最大摄食水平条件下,采用室内流水模拟实验法定量了其能量收支各组分和能量收支分配模式的温度影响。结果表明,在实验温度范围内,真鲷的摄食率、生长率、总代谢率和排泄率均随温度上升呈减速增长趋势, 二者之间的定量关系均可用对数曲线加以定量描述;真鲷的能量收支分配模式。11.2±1.98℃:100C=4.48F 9.55U 80.19R 5.78G;14.7±0.57℃:100C=2.28F 8.99U 74.56R 14.16G;19.4±0.44℃:100C=2.73F 8.00U 63.23R 26.03G;23.1±1.43℃: 100C=2.94F 8.23U 65.76R 23.07G。从分配模式可以看出,真鲷能量收支各组分的分配率随温度显著变化,其中代谢分配率和排泄分配率随温度升高呈U形变化趋势,而生长分配率和排粪分配率则恰恰相反。由于不同温度下真鲷的代谢能分别占了同化能的69.72%~93.28%,生长能则占6.72%~30.28%,故与其他鱼类相比,真鲷基本上属于低生长效率、高代谢消耗型鱼类。  相似文献   

8.
长江宜宾江段渔业资源调查   总被引:1,自引:0,他引:1  
长江上游是我国淡水鱼类种质资源最为丰富的地区之一。上游干、支流及其附属湖泊内,共分布有鱼类261种,包括国家一级保护野生动物白鲟、达氏鲟和中华鲟,二级保护野生动物胭脂鱼和川陕哲罗鲑。除珍稀鱼类外,长江上游分布有112种特有鱼类,占上游鱼类总数的42.95%。特有种所占比例之高,超过国内其它任何地区或水系。三峡工程建成后,将引起水域生态改变,并将使约40种鱼类受到不利影响。  相似文献   

9.
黑斑狗鱼,属鲑形目、狗鱼亚目、狗鱼科、狗鱼属,在我国仅产于黑龙江流域。黑斑狗鱼肉质坚韧少刺、味道鲜美,是人们非常喜爱的优质经济鱼类。黑斑狗鱼生活于寒冷地区水域,为冷水性鱼类,适温范围0℃-30℃,最适生长温度22℃-26℃。幼苗阶段以轮虫、小型枝角类、桡足类等浮游动物为食,稍大即捕食其他鱼类。饵料不足时会自相残食,为大型凶猛肉食性鱼类。  相似文献   

10.
唐山地区遵化县汤泉渔场利用地下热水资源(水温62℃)搞家鱼提前孵化,取得了可喜的成果。他们使用的是石家庄水泵厂出厂的10J80深井泵。10J80深井泵说明书明确规定:“泵输送水的温度不得超过40℃”由于地下水的水温较高,使用中泵经常出现故障。影响了象鱼提前孵化的进行。  相似文献   

11.
12.
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   

13.
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   

14.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

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