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1.
利用脑—脑垂体—肝脏轴调控鱼类生长   总被引:5,自引:0,他引:5  
本文综述了鱼类生长激素分泌的神经内分泌调节方面取得的研究进展,阐明脑(各种神经内分泌因子)-脑垂体(由生长激素细胞分泌的生长激素)-肝脏(肝细胞产生的类胰岛素生长因子)轴调控鱼类生长的作用,并在此基础上提出可供养鱼生产实践应用的基本途径。  相似文献   

2.
鱼类生长和营养代谢的激素调控   总被引:1,自引:0,他引:1  
本文综述了垂体生长激素、类固醇激素、甲状腺激素对鱼类生长中的蛋白质、脂肪、碳水化合物营养代谢的效应,激素在渔业生产的应用前景。  相似文献   

3.
鱼类摄食和生长的神经内分泌调控途径研究进展   总被引:2,自引:2,他引:2  
鱼类的生长与哺乳类相似,受脑(各种神经内分泌因子)一脑垂体(由生长激素细胞分泌的生长激素)一肝脏(肝细胞产生的类胰岛素生长因子)轴的调控,生长激素(Growth hor-mone,GH)和类胰岛素生长因子(Insulin-like growth factor,IGF)与鱼类生长发育关系十分密切,并且对鱼类的生长起主要调节作用[1~3]。而 GH的释放受到脑,特别是下丘脑合成与分泌的生长激素释放因子(GRF)和生长激素释放抑制因子(SRIF)的双重调控,通过外源药物加强鱼类自身GH(内源性的)的合成与…  相似文献   

4.
鱼类补偿性生长研究   总被引:10,自引:0,他引:10  
综述了鱼类补偿性生长的研究意义、国内外研究概况、补偿类型、补偿特点、补偿机制、影响因素、补偿性生长应用前景。  相似文献   

5.
本文综述了鱼类补偿生长的研究进展,对鱼类补偿生长的定义、类型、影响因素、试验设计、生理机制进行了分析。初步探讨了补偿生长的理论意义以及在水产养殖实践中的应用前景和存在的问题。  相似文献   

6.
2007和2008年5~10月间对辽宁省汤河水库鱼类进行了现场采集和分析,共收集到鱼类18种,分别隶属于5科18属。其中鲤科14种,占77.8%;鲿科、鲇科、鮨科、鳢科各1种,占22.2%。5月、8月、10月鲢、鳙比例占渔获物平均数的71.6%,年龄为1至5龄,其中2~4龄鱼比例占82%;鲢和鳙的体长生长和体重生长分别为:Lt=L∞[1-e-(kt-t0)]和Wt=W∞[1-e-(kt-t0)]3。  相似文献   

7.
饥饿对鱼类生长的影响   总被引:4,自引:0,他引:4  
不同种类的鱼对饥饿的耐受力和适应性特征不同.有关饥饿对鱼类影响的研究有助于了解鱼类适应饥饿的生态对策,对鱼类自然资源的保护、苗种培育、水产养殖等方面提供理论指导.本文综述了饥饿对鱼类生长、存活、行态、行为以及补偿生长等方面的研究进展.  相似文献   

8.
何玉慧  李响  石军 《水产学报》2024,37(9):099601-1-099601-21

鱼类是人类获取动物蛋白的重要来源,其主要可食用部分为肌肉组织。鱼类水产养殖的本质即通过适宜的养殖条件和技术,促使鱼类肌纤维快速增殖和迅速肥大,达到肌肉快速生长、提高养殖生产效益目的。鱼类肌肉生长的实质为肌纤维增殖和肌纤维增粗,即肌细胞不断融合形成更粗更大肌管的过程;肌管进一步分化、组装并表达一类肌肉特异性蛋白,最终形成两种不同类型的肌纤维:白色肌肉 (快肌)和红色肌肉 (慢肌)组织。本文系统总结了鱼类肌肉生长最新研究进展,包括鱼类肌纤维结构及形成过程,肌细胞增殖、迁移、分化及肌细胞生长的关键调控因子和信号通路;此外,重点解析了肌细胞融合的关键基因 (mymkmymx)及融合决定因素。另外,本文概述了肌肉生长基因资源在水产育种中的应用,阐述了利用营养条件改良鱼类肉质的可行性,并提出可结合遗传学和营养学手段,合理调节鱼类肌纤维增殖和增粗两种生长模式,实现肌肉快速增长和肉质改良。本综述可为鱼类速生优质品系培育提供理论基础和实践指导。

  相似文献   

9.
浅谈鱼类的补偿生长(Compensatory growth)   总被引:1,自引:0,他引:1  
综述了鱼类补偿生长的研究进展,对鱼类补偿生长的定义、类型、特点、影响因素、研究方法、应用、生理机制及补偿生长中的生理生化变化进行了分析。初步探讨了补偿生长研究存在的问题与发展趋势。  相似文献   

10.
乳酸菌Lactobacillus能调节肠道微生物平衡,促进鱼类的生长和发育,增强鱼类的免疫力和抵抗力,是一种安全的微生物添加剂,广泛应用于饲料工业。本文通过综述乳酸菌对鱼类生长的影响及其促生长机理,探讨乳酸菌在鱼类养殖中的应用和乳酸菌对鱼类生长的基础及应用等未来的研究方向,可为大规模生产鱼类乳酸菌饲料提供参考。  相似文献   

11.
    
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.
14.
    
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   

15.
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   

16.
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   

17.
Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.  相似文献   

18.
    
This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO2 and ions should be more often evaluated. Plasma Na+ and Cl are very useful markers of acidosis, due to their respective exchange for H+ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.  相似文献   

19.
The toxic effects of Cd2+ on Ca2+ influx kinetics in developing tilapia (Oreochromis mossambicus) larvae were evaluated. Addition of 20 µg l-1 of Cd2+ to the environment of 0 and 3 day-old larvae competitively inhibited the Ca2+ uptake within 4h resulting in a great increase in Km values for Ca2+ influx (19.3 and 17.4 fold, respectively) as compared with their respective controls. Consequently, the actual Ca2+ influx of larvae in solutions of 0.2 mM Ca2+ are suppressed by 32–45%. Also, 3 day-old larvae were more sensitive to internally accumulated Cd2+ than 0 day-old larvae. Although the Ca2+ influx in 0 and 3 day-old larvae may be restored to the levels of their respective controls with 24h of being transferred to a 20 µg l-1 Cd2+ solution, total body Ca2+ content was significantly reduced in 3 day-old larvae. Increased Ca2+ uptake efficiency ensures sufficient Ca2+ for normal growth. However, rapid increase in Ca2+ influx after hatching also leads to higher Cd2+ uptake. Exposure to Cd2+ will lead to a drop in body Ca2+ content resulting in retardation of larval growth. Therefore, we conclude that if Ca2+ uptake is interfered with at this critical stage of development, larvae will not be able to maintain normal levels of body Ca2+ and will show signs of Cd2+ poisoning.  相似文献   

20.
Abstract– Literature evidence suggests that lake-dwelling longnose gar (Lepisosteus osseus) enter tributary streams to spawn, Until the present study, the dynamics of this breeding migration had never been investigated quantitatively. During the summers of 1991 and 1992, longnose gar were captured as they entered Weaubleau Creek, Missouri, a tributary of Harry S. Truman Reservoir. The in-stream spawning migration began in early April and ended in late May, and was positively correlated with stream flow and water level, and negatively correlated with water temperature. In-stream residence times ranged from 15 to 94 days, with males exhibiting longer residence times than females. Once in-stream, longnose gar travelled as far as 10 km upstream and occupied certain pools at greater relative frequencies. Although the reason for this preferential utilization is not completely understood, it may relate to pool depth and riffle proximity. Longnose gar disperse from the spawning stream great distances, with gar captured in Weaubleau Creek being recaptured up to 48 km away. This information should provide fisheries biologists the means to consider the reproductive ecology of this species in their conservation and management decisions.  相似文献   

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