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力竭运动常出现于虾类养殖过程和野生环境中,斑节对虾(Penaeus monodon)是中国沿海重要养殖和增殖放流品种,但尚无关于斑节对虾力竭运动后生理恢复过程报道。该研究以斑节对虾幼虾为实验对象,在室内水槽使用抄网追逐斑节对虾幼虾,模拟迫使其进行力竭运动实验,探究其力竭运动后抗氧化能力恢复过程。结果显示,力竭运动后0 h,幼虾体内的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和谷胱甘肽过氧化物酶(GSH-Px)的活性,总抗氧化能力(T-AOC)和丙二醛(MDA)含量,均与对照组无显著差异;1~12 h,SOD、CAT、POD活性、MDA含量和T-AOC持续下降,GSH-Px活性无显著变化;24 h,SOD、CAT和POD活性显著降低,GSH-Px活性、MDA含量和T-AOC显著升高;72 h,SOD和CAT活性仍显著低于对照组,GSH-Px、POD活性和MDA含量恢复至对照组,T-AOC显著高于对照组。在力竭运动过程中,幼虾的酶促抗氧化系统未被激活;幼虾的抗氧化能力在力竭运动后的24 h内较低,不宜再次受刺激;幼虾的抗氧化能力在力竭后24 h后显著上升,并保持较长时间。 相似文献
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温度对雨生红球藻生长、虾青素累积和抗氧化能力的影响 总被引：1，自引：0，他引：1
本文研究了不同培养温度对雨生红球藻细胞密度、生长速率、虾青素含量、超氧化物歧化酶（SOD）活性、谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)的影响。结果表明藻细胞密度、生长速率和虾青素含量随温度的增加先升高后下降,SOD活性 和GSH-Px活性随着温度的增加而逐渐上升,而T-AOC则随温度的增加先升高后下降,然后再升高;藻细胞密度、生长速率、虾青素含量和T-AOC均在培养温度为25℃时达到最大值,而SOD活性和GSH-Px活性在培养温度为35℃时最高;藻细胞内虾青素和抗氧化酶的抗氧化活性互为补充。本研究结果为雨生红球藻的大规模培养和虾青素的规模化生产和应用提供了理论基础。 相似文献
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高pH胁迫对克氏原螯虾的急性毒性和鳃、肝胰腺中酶活性及组织结构的影响 总被引：4，自引：3，他引：1
研究了高pH胁迫对克氏原螯虾鳃、肝胰腺中酶活性的变化,以及对鳃、肝胰腺组织结构的影响。在得出96 h L C_(50)的基础上,设置对照(pH7.6)和实验(pH10.2)2个pH处理组,进行96 h高pH胁迫,于胁迫后0、2、8、24和96 h测定鳃Na~+-K~+-ATP酶、乳酸脱氢酶(lactate dehydrogenase,LDH)、延胡索酸还原酶(fumarate reductase,FRD)、肝胰腺超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)的活性以及丙二醛(malondialdehyde,MDA)的含量,并采集完整的鳃、肝胰腺做组织切片观察。结果发现,96 h LC50 pH值为10.194。高pH应激后,实验组鳃Na+-K+-ATP酶、LDH和FRD的活性呈上升趋势,pH胁迫8 h后与对照组差异显著(P0.05);随胁迫时间的延长,实验组肝胰腺MDA含量的变化趋势与LDH和FRD相似,CAT活性呈先上升后下降趋势,SOD活性起初变化不大,pH胁迫24 h后出现明显下降(P0.05)。鳃和肝胰腺的组织观察表明,随着pH胁迫时间的延长,鳃呼吸上皮细胞逐渐脱落,角质层受损、破裂,鳃叶受损程度逐渐加剧;肝胰腺小管基膜破损,小管内空泡增多、体积增大,肝细胞细胞数量减少。研究表明,高pH胁迫对克氏原螯虾代谢会产生影响,同时导致氧化应激,并会对鳃和肝胰腺的组织结构造成损伤,影响其生物学功能。 相似文献
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为探究福建牡蛎(Crassostrea angulata)在急性低氧胁迫下鳃组织的氧化应激反应和闭壳肌的能量代谢, 本研
究设置6 个溶解氧浓度梯度(0.5 mg/L、1.0 mg/L、1.5 mg/L、2.0 mg/L、3.0 mg/L、4.0 mg/L), 对福建牡蛎实施持续
96 h 低氧胁迫处理。采用酶联免疫分析技术分析低氧胁迫第6、12、24、48、72、96 小时福建牡蛎鳃组织的总抗
氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性和丙二醛(MDA)含量以及闭壳肌组织的碱
性磷酸酶(AKP)活性、乳酸脱氢酶(LDH)活性和糖原含量。结果显示: (1) 6~24 h 的低氧胁迫下, T-AOC、SOD 活性
和MDA 含量呈现先升高后降低的现象, CAT 活性则表现为先降低后升高。胁迫24 h 时全部处理组的MDA 含量和
部分处理组的T-AOC 和SOD 活性恢复至对照组水平。24~96 h 的低氧胁迫下, T-AOC、SOD 活性和MDA 含量呈
现先升高后降低再升高, 部分处理组CAT 活性持续降低。低氧胁迫96 h, 全部处理组的T-AOC 活性和部分处理组
的MDA 含量及CAT 活性恢复至对照组水平; 除1.0 mg/L 浓度组与对照组无显著差异(P>0.05), 其余处理组SOD
活性显著低于对照组(P<0.05)。(2) 在96 h 低氧胁迫过程中, 部分处理组LDH 活性在6~12 h 和24~48 h 期间显著
升高(P<0.05); 各低氧处理组的AKP 活性随胁迫时间增加先降低后升高; 糖原含量随低氧胁迫时间增加发生不同
程度的下降, 当胁迫至96 h 时, 除0.5 mg/L 浓度组的糖原含量显著降低(P<0.05)之外, 其他组糖原含量恢复到与对
照组无显著差异(P>0.05)。上述结果表明, 急性低氧胁迫下, 福建牡蛎通过调整体内不同酶活性变化, 改善机体氧
化应激反应和能量代谢的收支平衡, 但极端的低氧环境胁迫仍会对福建牡蛎造成不可修复的损伤。 相似文献
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《淡水渔业》2021,(4)
为探讨高pH急性和慢性胁迫对克氏原螯虾(Procambarus clarkii)非特异性免疫和抗氧化能力的影响,分别设置对照(pH 7.6)和试验(pH 10.2)2个pH处理组,对克氏原螯虾进行急性(0 h、3 h、6 h、12 h、24 h、5 d)和慢性(10 d、15 d)pH胁迫试验。结果显示:高pH应激后,试验组血浆总蛋白(TP)含量和酸性磷酸酶(ACP)活性呈上升趋势。高pH急性胁迫下,24 h内试验组血浆碱性磷酸酶(AKP)呈先上升后下降趋势,5 d AKP活性显著上升;试验组血浆血糖(GLU)及皮质醇(CORTISOL)含量于pH胁迫5 d后达到峰值,且显著高于对照组;试验组肝胰腺超氧化物歧化酶(SOD)活性呈下降趋势,并于24 h开始显著低于对照组;试验组肝胰腺谷胱甘肽过氧化物酶(GSH-Px)活性在3～24 h显著低于对照组;试验组鳃乳酸脱氢酶(LDH)活性先下降后上升。高pH慢性胁迫下,试验组血浆AKP、ACP活性显著高于对照组;试验组血浆GLU及CORTISOL含量、鳃LDH活性呈下降趋势,肝胰腺SOD则呈上升趋势;肝胰腺GSH-Px、MDA水平于胁迫10 d时达到峰值。结果表明,高pH急性胁迫会对克氏原螯虾的免疫防御机制产生影响,导致氧化应激,随着胁迫时间的延长(慢性胁迫),机体部分非特异免疫和抗氧化指标逐步恢复。 相似文献
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为探讨盐胁迫对雨生红球藻(Haematococcus pluvialis)虾青素合成的影响与机理,以及雨生红球藻各抗氧化机制之间的关系,本研究采用生化和分子生物学方法研究了不同浓度(0.04 mol/L、0.08 mol/L、0.12 mol/L和0.16 mol/L)和不同时间(3 d、6 d和9 d)的盐(Na Cl)胁迫对雨生红球藻生长、虾青素积累、番茄红素β-环化酶(Lcy)、β-胡萝卜素羟化酶(Crt R-B)和β-胡萝卜素酮化酶(Bkt)基因表达、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)的活性以及丙二醛(MDA)含量的影响。结果表明,各胁迫时间的雨生红球藻的密度均随着盐胁迫浓度的增加而不断下降,在盐胁迫的第9天,雨生红球藻的死亡率和孢子比例均随着盐胁迫浓度的增加而不断升高;雨生红球藻虾青素含量、Lcy、Crt R-B和Bkt基因表达量均随着盐胁迫浓度和时间的增加而不断提高;雨生红球藻SOD、CAT和GSH-Px活性以及MDA含量在不同浓度和不同时间的盐胁迫下与对照组(0.00 mol/L Na Cl)相比均升高,且在不同时间的0.12 mol/L Na Cl胁迫下与对照组相比均显著升高(P0.05);雨生红球藻虾青素含量、Lcy、Crt R-B和Bkt基因表达量在盐胁迫的早期(第3天)和中期(第6天)阶段较低,在盐胁迫的后期(第9天)阶段较高,而SOD、CAT和GSH-Px活性以及MDA含量在盐胁迫的早期和中期阶段较高,在盐胁迫的后期阶段较低。实验结果说明了适当浓度和时间的盐胁迫能促进雨生红球藻累积虾青素,雨生红球藻在盐胁迫下主要是通过提高虾青素合成相关酶基因的转录水平来促进虾青素的合成,其虾青素和抗氧化酶的抗氧化活性可能互为补充,共同保护雨生红球藻免受盐胁迫的氧化损伤。 相似文献
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氨氮胁迫与恢复对罗氏沼虾幼虾非特异性免疫的影响 总被引：1，自引：0，他引：1
在温度为(25±1)℃、p H为8. 0±0. 5条件下采用生物毒性实验方法研究了氨氮对罗氏沼虾(Macrobrachium rosenbergii)幼虾半致死浓度,并设置0、0. 43、0. 64、0. 85、1. 06 mg·L~(-1)5个浓度研究氨氮胁迫48 h及恢复48 h对罗氏沼虾非特异性免疫的影响。结果显示:非离子氨对罗氏沼虾幼虾24、48、72、96 h半致死浓度分别为4. 25、2. 35、1. 86、1. 54 mg·L~(-1),安全浓度为0. 154 mg·L~(-1)。氨氮胁迫48 h,罗氏沼虾SOD活性显著升高(P 0. 05),而CAT和GSH-Px活性变化不显著(P 0. 05); 0. 43、0. 64、1. 06 mg·L~(-1)氨氮胁迫组罗氏沼虾MDA含量显著高于对照组(P 0. 05)。氨氮胁迫后恢复48 h,各组SOD活性均较胁迫时显著下降(P 0. 05),但除0. 85 mg·L~(-1)组外的其它试验组仍显著高于对照组(P 0. 05); 0. 85、1. 06 mg·L~(-1)组CAT活性较胁迫状态显著下降(P 0. 05);试验组与对照组MDA含量无显著差异(P 0. 05)。结果表明,低浓度氨氮短期胁迫对罗氏沼虾造成的氧化损伤在解除胁迫后可修复,但肌肉仍处于应激状态。 相似文献
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【目的】为研究饲料中添加不同水草粉对克氏原螯虾生长、消化酶、抗氧化酶活性及色泽的影响,【方法】本研究 通过在饲料中分别添加15%的伊乐藻、轮叶黑藻、苦草、金鱼藻和喜旱莲子草5种水草粉(分别标记为Diet 2~6组),对照组饲料无水草粉添加（标记为Diet 1组）,对克氏原螯虾幼虾进行为期60 d的养殖实验。【结果】结果显示：水草组(Diet 2~6组)成活率(SR)与Diet 1组无显著差异,Diet 3~5组增重率(WGR)及特定生长率(SGR)均与Diet 1组无显著差异,而Diet 3组肝胰腺指数(HSI)显著高于Diet 1组。在肝胰腺中,Diet 2~6组脂肪酶(LPS)活性显著高于Diet 1组,且Diet 5组LPS和α-淀粉酶(α-AL)活性最高,而胃蛋白酶活性为Diet 2组最高,Diet 2~3及5组纤维素酶(CL)活性显著高于Diet 1组;在肠道中,Diet 2~6组4种消化酶活性均低于Diet 1组。Diet 3~6组头胸甲和肌肉总类胡萝卜素、头胸甲虾青素含量及卵巢中总类胡萝卜素、虾青素、叶黄素和β-胡萝卜素含量均显著高于Diet 1组。Diet 2~6组头胸甲及卵巢的红度(a*值)和黄度(b*值)均显著高于Diet 1组,而亮度(L*值)却低于Diet 1组。在肝胰腺中,Diet 2~6组总超氧化物歧化酶(T-SOD)活性均显著高于Diet 1组且在Diet 5组最高,Diet 4组总抗氧化能力(T-AOC)活性最高,Diet 2组丙二醛(MDA)含量最高;血清中,Diet 6组T-AOC活性最高,但各组间T-SOD活性和MDA含量无显著差异。【结论】综上,添加15%轮叶黑藻、苦草和金鱼藻水草粉到饲料中,对克氏原螯虾生长无负面影响,有利于体内类胡萝卜素、虾青素的积累,改善克氏原螯虾头胸甲和卵巢色泽的同时提升抗氧化能力。 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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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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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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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
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.
An overview of stress physiology of fish transport: changes in water quality as a function of transport duration 下载免费PDF全文
下载免费PDF全文 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