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1.
似刺鳊鮈耗氧率和窒息点的初步研究 总被引：1，自引：0，他引：1
试验测定了似刺鳊鮈(Paracanthobrama guichenoti)的耗氧率和窒息点,并对耗氧率的昼夜变化规律以及体重对其窒息点的影响进行了研究。结果表明,似刺鳊鮈的耗氧率与温度和体重之间有极显著复相关关系。在试验温度(15～30℃)条件下,似刺鳊鮈的耗氧率随温度的升高而增大,随体重的增加而降低;耗氧率(R0)与温度(T)和体重(W)的二元线形回归方程是:R0=0.0160T+0.0002W-0.1600,复相关系数为0.9460;似刺鳊鮈的耗氧率具有昼夜节律性,耗氧高峰出现在7∶00,低谷在21∶00;似刺鳊鮈的窒息点与体重显著相关,窒息点A(mg/L)与体重W(g)的关系为:A=0.3463W0.2835,r=0.9050。研究结果可为似刺鳊鮈养殖生产中制定合理的放养密度和养殖工艺提供参考依据。 相似文献
2.
试验测定了似刺鳊鮈（Paracanthobrama guichenoti）的耗氧率和窒息点,并对耗氧率的昼夜变化规律以及体重对其窒息点的影响进行了研究。结果表明,似刺鳊鮈的耗氧率与温度和体重之间有极显著复相关关系。在试验温度（15～30℃）条件下,似刺鳊鮈的耗氧率随温度的升高而增大,随体重的增加而降低;耗氧率（R0）与温度（T）和体重（W）的二元线形回归方程是：R0=0.0160T＋0.0002W-0.1600,复相关系数为0.9460;似刺鳊鮈的耗氧率具有昼夜节律性,耗氧高峰出现在7∶00,低谷在21∶00;似刺鳊鮈的窒息点与体重显著相关,窒息点A（mg/L）与体重W（g）的关系为：A=0.3463W0.2835,r=0.9050。研究结果可为似刺鳊鮈养殖生产中制定合理的放养密度和养殖工艺提供参考依据。 相似文献
3.
山女鳟耗氧量与体重、水温的关系的研究 总被引：3，自引：0，他引：3
通过对体重0．53g和75．58g的山女鳟，在7℃、10℃、13℃、16℃、19℃，5个范围耗氧的测定，研究了山女鳟耗氧量与体重、水温的关系，结果表明：耗氧量随着体重和水温的增加而增加，耗氧率随着体重的增加而减少，在13℃-16℃水温范围内，水温增加但耗氧率增加不明显，水温在16℃时，耗氧量与体重的关系为：R=0．3621W^7848(R：耗氧量mg／h．尾，W：体重，g)，在体重0．53g时，耗氧量与水温的关系为：R=0．0173T-0．0393，75．58g时，耗氧量与水温的关系为：R=0．825T-1．725(R：耗氧量mg／h．尾，T：水温，℃)。山女鳟耗氧率具有昼夜变化，表现出明显的节律性，在13：00时耗氧率达到最高值，22：00时达到最低值。山女鳟的窒息点在1．2—1．98mg／L。 相似文献
4.
褐菖鲉耗氧率及窒息点的初步研究 总被引：5，自引：0，他引：5
应用测定流水中溶氧量的方法,对褐菖鲉耗氧率、窒息点及耗氧率昼夜变化进行研究。结果表明,在pH8.0、盐度24.5、水温17℃的水质条件下耗氧率昼夜变化不明显(P=0.422),平均值晚上略高于白天,凌晨05∶00耗氧率最高,为233.04±25.36mg/kg·h;耗氧率、耗氧量与体重的关系分别为QR=1433.9W-0.7077(R2=0.992,P<0.001)、QC=1.4298W0.2926(R2=0.956,P<0.001);水温对褐菖鲉的耗氧率有极显著影响(P<0.01);pH值在8.0时耗氧率最低。窒息点随着个体的增大而降低,相同体重的鱼窒息点随着水温的升高而升高。 相似文献
5.
利用简易密闭的流水装置,对普安鲫(Carassius auratus)鱼苗的耗氧率进行了初步研究;选择体重为1.40～2.50 g的小规格及21.20～33.31 g大规格普安鲫鱼苗,研究其昼夜耗氧率的变化规律以及水温、体重对其耗氧率的影响。结果表明,温度对普安鲫鱼苗耗氧率有显著影响,耗氧率随温度的增加而升高,随体重的增加而降低。2种规格普安鲫鱼苗的昼夜耗氧率变化曲线基本一致,日均(7∶00～17∶00)耗氧率0.1700 mg/(g.h)与夜均(19∶00～5∶00)耗氧率0.1721 mg/(g.h)相似;其中,小规格普安鲫在23∶00出现耗氧率低峰0.1253 mg/(g.h),5∶00出现耗氧率高峰0.2647 mg/(g.h);大规格普安鲫在21∶00出现耗氧率低峰0.0909 mg/(g.h),7∶00出现耗氧率高峰0.2375 mg/(g.h)。 相似文献
6.
2008年4～8月,采用Winkler法研究了70日龄（平均全长37.68mm,平均体重1.07g）和105日龄（平均全长65.71mm,平均体重5.58g）的条石鲷在不同温度（15、20和25℃）、不同盐度（20、25和30）下的耗氧率、窒息点及耗氧率昼夜变化。结果表明,105日龄组的相对耗氧率明显低于70日龄组,但个体耗氧量明显高于70日龄组;耗氧率随幼鱼体重的增加而相对减少。盐度一定时,温度升高,相对耗氧率和个体耗氧量都随之增大。盐度对70日龄幼鱼组的耗氧率影响显著（P〈0.05）,对105日龄幼鱼组影响不显著（P〉0.05）。盐度25左右、温度20～25℃时是条石鲷苗种培育和生长的最适盐度和最适温度。条石鲷在温度15～25℃、盐度20～30下的窒息点为1.6021～2.9538mgO2/L,窒息点随着个体的增大而降低;温度、盐度对条石鲷窒息点的影响均不显著（P〉0.05）。条石鲷耗氧率的昼夜变化明显,白天的耗氧率平均为0.9459mgO2/g.h,夜间平均为0.2727mgO2/g.h,白天的耗氧率是夜间的3～5倍,条石鲷白天代谢旺盛并持续到夜间22∶00左右。 相似文献
7.
在水温(15±0.5)℃下,采用流水和静水呼吸室法,测定(1.88±0.33)g、(4.24±0.61)g和(7.27±0.76)g 3种规格北方须鳅的耗氧节律,不同水温下(0、2、5、10、15、20、25、27℃和30℃)3种规格北方须鳅的耗氧率和窒息点。试验结果表明,北方须鳅在白天(8:00—16:00)耗氧率略高于夜间(18:00—6:00),但差异不显著(P0.05),昼夜变化对其耗氧率无影响;在12:00—20:00为耗氧率高峰,显著高于22:00—次日10:00(P0.05)。北方须鳅耗氧率随水温(2~27℃)的升高逐渐增加,呈正相关(P0.01),其24h耗氧率(y)随体质量(x)的增加而下降,符合y=0.1426x-0.2055(r2=0.9414)。(1.88±0.33)g北方须鳅24h耗氧率与(7.27±0.76)g和(4.24±0.61)g北方须鳅耗氧率呈极显著性差异(P0.01),(4.24±0.61)g北方须鳅24h耗氧率与(7.27±0.76)g北方须鳅耗氧率无显著性差异(P0.05)。在2~10℃,北方须鳅临界窒息点随水温的上升呈下降趋势,在10℃时临界窒息点最低,而后随水温的升高(15~27℃),临界窒息点逐渐升高。结果初步揭示,不同生长发育阶段的北方须鳅24h耗氧率变化规律以及水温和体质量对其耗氧率和窒息点的影响,为其健康增养殖、活体运输以及生态保护等提供了参考。 相似文献
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9.
匙吻鲟幼鱼耗氧率和窒息点的初步研究 总被引：1，自引：0，他引：1
在水温19.0～20.0℃,测定了匙吻鲟(体重156.42g±23.46g)的耗氧率和窒息点.结果表明:匙吻鲟幼鱼耗氧率具有昼夜节律性,耗氧率从1:00-17:00呈上升趋势,17:00至次日1:00呈下降趋势.匙吻鲟的昼夜平均耗氧率为0.23mg/g·h),耗氧率高峰值出现在15:00-19:00,低峰值出现在23:00-3:00.平均耗氧率7:00-19:00明显高于21:00-5:00(P<0.01).匙吻鲟幼鱼的窒患点为2.81 mg/L(以O2计). 相似文献
10.
采用实验生态学方法,在16、20、24、28和32℃下测定了当年(体质量0.57~3.82g)和1冬龄(17.39~54.40g)拉氏Phoxinus lagowskii的耗氧率及其昼夜变化和窒息点。结果表明:拉氏昼间耗氧率高于夜间,当年苗种耗氧率峰值在中午和傍晚,而成鱼的仅在傍晚;在16~32℃范围内,体质量为(1.72±0.60)g的拉氏耗氧率(OR)随温度(T)升高而增加,其关系式为OR=0.1734e0.2277T(R2=0.9911),窒息点在1.53~1.65mg·L-1之间,平均(1.59±0.04)mg·L-1;在20~24℃下,拉氏(0.77~52.4g)耗氧率(OR)随体质量(W)增加而呈下降趋势,其关系式为OR=0.3248W-0.2206(R2=0.8076),窒息点在1.10~1.55mg·L-1之间,均值为(1.29±0.19)mg·L-1。 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 
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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
12.
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
13.
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
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