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1.
(Hemiculter leucisculus)和鱇白鱼(Anabarilius grahami)分别是抚仙湖的外来鱼类和土著鱼类。研究了不同营养状态(低、中、高)水体中二者肝脏酶活性的变化;其中,低营养状态水体组是中、高营养水体组的对照。养殖40d后,随着水体营养状态的提高,和鱇白鱼肝脏中的谷草转氨酶(AST)、谷丙转氨酶(ALT)和乳酸脱氢酶(LDH)活性均逐渐降低;中、高营养水体中歺鱼又的超氧化物岐化酶(SOD)活性显著低于对照组,而3个处理组鱇白鱼的超氧化物岐化酶活性没有显著差异。由此推测,富营养化有可能减弱歺鱼又和鱇白鱼肝脏的正常功能,而歺鱼又在高营养水体中可能更容易受到氧化胁迫的威胁。  相似文献   

2.
鱇浪白鱼是抚仙湖特有土著鱼类,它以独特的鱼性、鲜美的风味和古老的"车水捕鱼"极负盛名。经过多年的研究,抚仙湖鱇浪白鱼养殖技术日趋成熟,在海口镇河谷地带,已发展连片的鱇浪白鱼流水养殖鱼池150×667m2,年产商品鱇浪白鱼15 t,经济效益可观。介绍了鱇浪白鱼流水养殖技术。  相似文献   

3.
2012年10-11月三峡水库高水位期以及2013年5-6月三峡水库低水位期调查了汉丰湖的鱼类资源,研究三峡水库高、低水位下汉丰湖鱼类种类组成、优势种类、生物多样性以及群落相似性,并对不同水位下汉丰湖鱼类群落结构的扰动特征和增殖放流情况进行了辨识和探讨。共采集到鱼类17 553尾,42种,隶属于4目7科31属。其中三峡水库低水位时采集到鱼类33种,高水位时采集到鱼类34种。汉丰湖优势种类在三峡水库低水位时为银鮈Squalidus argentatus、似鳊Pseudobrama simoni、歺又鱼Hemiculter leucisculus、蒙古鲌Culter mongolicus mongolicus和鲤Cyprinus(Cyprinus)carpio;在三峡水库高水位时为似鳊、鲤、鲫Carassius auratus、张氏歺又鱼Hemiculter tchangi和鲇Silurus asotus。汉丰湖鱼类Shannon-wiener多样性指数(H’)、Simpson优势度指数(D)、Pielous均匀度指数(E)和Margalef种类丰富度指数(R)在三峡水库低水位时分别为1.63、0.67、0.46和3.52;在三峡水库高水位时分别为2.15、0.80、0.61和4.34。三峡水库低、高水位时汉丰湖鱼类群落结构的Bray-Curtis相似性仅为26.52%,喜缓、静水生境的银鮈、张氏歺又鱼、鲤、歺又鱼、鲫、鲇、似鳊和蒙古鲌是群落结构差异的主要种类,累积差异贡献率为90.67%。汉丰湖鱼类群落在高水位时受到中等程度的干扰,而在低水位时受到严重干扰。建议每年均放流鲢、鳙、草鱼并进一步加大放流规模。  相似文献   

4.
盐度对咸海卡拉白鱼生长及组织学特征的影响   总被引:3,自引:1,他引:3  
将咸海卡拉白鱼(Chalcalburnus chalcoides aralensis)在不同盐度(0.24、2.12、3.95、5.90、7.64、9.38、11.32、13.62、15.55)水体中饲养30d后,在盐度11.32以下的实验组鱼的成活率为100%;盐度13.62时,24h全部死亡;盐度15.55时,12h死亡率达100%.盐度为2.12和3.95组实验鱼的日均增重和特定生长率与对照组(盐度为0.24组)无明显差异(P>0.05);盐度为5.90和7.64组鱼的日均增重和特定生长率均低于对照组(P<0.05),生长受到抑制;盐度为3.95、5.90和7.64组鱼的血糖浓度均低于对照组(P<0.05);盐度为5.90和7.64组肝脏谷丙转氨酶(GPT)活性显著高于对照组(P<0.05).组织学观察发现,低盐度(2.12和3.95)组鱼与对照组相比无病理性变化.而中盐度(5.90和7.64)组鱼的鳃上皮细胞发生肥大、增厚;肝细胞发生肿大,细胞变形;肾小囊体积缩小,肾小球囊腔增大;各级肾小管出现萎缩,管腔缩小.高盐度(9.38和11.32)组鱼鳃上皮细胞增厚,水肿加重,鳃上皮隆起,上皮细胞坏死和脱落;肝细胞肿大加重,部分细胞核溶解出现肝组织空泡化;肾小囊严重萎缩、退化,肾小球囊腔继续增大;肾小管上皮细胞坏死,出现肾充血.生长、生化指标和组织学观测结果表明,咸海卡拉白鱼生长的最适盐度为5.90以下.  相似文献   

5.
为了探讨急性氨氮胁迫对黄颡鱼组织中抗氧化酶活性及HSP70和HSP90基因mRNA表达水平的影响,实验随机挑选了360尾黄颡鱼[初体质量(17.25±0.05)g],分别暴露于含有0(对照)、5.70(低浓度组)、28.50(中浓度组)和57.00(高浓度组)mg/L总氨氮浓度的水体中,进行96 h的急性胁迫实验。实验开始后,分别于0、12、24、48和96 h取样。结果显示,氨氮胁迫发生后,低、中浓度组实验鱼肝脏中超氧化物歧化酶(SOD)活性呈先升高后降低趋势,而高浓度组则持续降低;低、中、高浓度组实验鱼肝脏中丙二醛(MDA)含量在胁迫开始后显著升高;3 h时,高浓度组实验鱼肝脏中SOD活性达到最低,而MDA含量最高;24 h后,高浓度组实验鱼肝脏中过氧化氢酶(CAT)活性显著升高;低、中、高浓度组实验鱼肝脏中HSP70基因的mRNA表达量呈先降低后升高趋势,而鳃中HSP70基因表达量持续升高,但脑中HSP70基因在0 h后显著降低;氨氮胁迫3 h时,低、中、高浓度组实验鱼肝脏和脑中HSP70基因表达量显著低于对照组,而在鳃中正好相反;相比HSP70基因,高氨氮浓度组实验鱼肝脏和鳃中HSP90基因的mRNA表达量在24 h时达到最高。研究表明,不同浓度的氨氮胁迫会对黄颡鱼抗氧化酶活性造成不同程度的抑制,原因与丙二醛的积累量有关;相比HSP90基因,黄颡鱼HSP70基因的表达量在氨氮胁迫发生后迅速上调,这种生理调控机制提示HSP70在应对急性氨氮胁迫时发挥着更重要的作用。  相似文献   

6.
为探究桂江鱼类群落结构现状,维持水生生物多样性,于2015年1月(冬)、4月(春)、7月(夏)和10月(秋),对桂江平乐(S1)、昭平(S2)、五将(S3)、马江(S4)、木格(S5)、大郎(S6)、京南(S7)、倒水(S8)、梧州(S9)共计9个采样点,进行4次鱼类资源调查。结果表明,本次调查共采集鱼类93种,隶属于6目、17科、 66属,其中以鲤形目为主(63种),占总种数的67.74%。鱼类相对多度(Relative density)显示,全年优势种为歺又鱼(Hemiculter leucisculus),占总个体数的12.75%。不同季节的优势种有差异,冬季优势种为伍氏半歺又鱼(Hemiculterella wui)、歺又鱼和宽鳍鱲(Zacco platypus);春季优势种不明显,个体数较多的有南方拟歺又鱼(Pseudohemiculter dispar)和泥鳅(Misgurnus anguillicaudatus);夏季优势种为歺又鱼、大眼华鳊(Sinibrama macrops)和南方拟歺又鱼;秋季优势种为歺又鱼、莫桑比克罗非鱼(Tilapia mossambicus)和尼罗罗非鱼(T.niloticus)。无度量多维排序图(NMDS)和单因素相似性分析(ANOSIM)结果显示,除夏季与秋季外(P=0.1780.05),其余季节之间鱼类群落结构存在显著性差异(P0.05),这可能是珠江水系鱼类繁殖期(4-6月)及降水的季节性变化所致。采样点S1与S7、S8、S9,S6与S7、S8、S9,S2与S6、S9之间存在显著性差异,河流库区化、过度开发以及外来入侵种是导致鱼类群落结构空间变化显著的原因。  相似文献   

7.
为评价光合细菌在罗非鱼养殖过程中使用效果的生物学指标,本试验设计在养殖罗非鱼的水体里添加不同浓度的光合细菌,通过测定罗非鱼酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、谷草转氨酶(AST)、谷丙转氨酶(ALT)、溶菌酶(LZM)五种免疫酶活性指标,探讨在养殖水体里添加光合细菌对罗非鱼的免疫酶活性及生长性能的影响。结果表明:添加光合细菌的浓度为104cfu/mL的鱼血清的ACP活性显著高于其他组,光合细菌的浓度为105cfu/mL的鱼血清的AKP活性显著高于其他组,光合细菌的浓度为103cfu/mL的鱼血清AST活性显著高于其他组,光合细菌的浓度为104cfu/mL和105cfu/mL添加组的鱼血清ALT活性显著高于其他组,光合细菌的浓度为104cfu/mL的鱼血清的LZM活性显著高于其他组,且实验组显著高于对照组。为推广光合细菌在罗非鱼养殖过程中提高免疫功能提供了理论依据。  相似文献   

8.
中药复方Ⅱ对鲤鱼生长和免疫功能的影响   总被引:2,自引:0,他引:2  
研究中药复方Ⅱ对鲤鱼生长和免疫功能的影响.选用体格健康的鲤鱼80尾,平均分成4组,每组20尾.设4个处理组,即基础饲料组(对照组)和3个基础饲料加中药组(实验组).3个实验组设了3个中药添加量.用以上4种饲料对实验鱼进行了120 d的饲养后,测定鲤鱼的生长性能、白细胞吞噬功能、溶菌酶活性和超氧化物岐化酶活性.与对照组相比,实验组饲料系数(FCR)、饲料转化率(FUE)、相对增重率(RWG)、瞬时增重率(SGR)、白细胞吞噬百分比(PP)、吞噬指数(PI)、溶菌酶和超氧化物岐化酶(SOD)活力均明显增高.但低剂量组与对照组相比,差异不显著(P>0.05).说明在饲料中添加中药复方Ⅱ能明显增强鲤鱼的生长性能和免疫功能.  相似文献   

9.
为研究黄曲霉毒素B1(Aflatoxin B1, AFB1)对黄颡鱼幼鱼生长、肠道消化酶及肝脏功能的影响,用添加不同梯度黄曲霉毒素B1(AFB1)(0、50、100和200μg/kg)的4种等氮等脂配合饲料饲喂初始体质量为(6.00±0.10) g的黄颡鱼幼鱼8周。结果显示:(1)饲料中添加AFB1对黄颡鱼幼鱼的存活率、饲料系数和特定生长率等均无显著影响,但使胰蛋白酶活性显著提高,而高含量AFB1(100和200μg/kg)显著降低肠道淀粉酶和脂肪酶活性;(2)随着AFB1添加量的上升,血清中谷丙转氨酶、谷草转氨酶活性及葡萄糖、甘油三酯、总胆汁酸和总胆固醇含量显著升高,肝脏中谷丙转氨酶、谷草转氨酶活性显著下降;(3) AFB1添加组的肝脏过氧化氢酶活性和丙二醛含量显著高于对照组,100和200μg/kg AFB1组超氧化物歧化酶活性显著高于对照组,其余各组无显著差异;(4) AFB1添加组肝脏sod基因及炎性因子il-1β基因的相对表达量显著上调,200μg/kg AFB1组cat基因及炎性因子il-8、il-10相对表达量显著上调;(5)通过组织学观察,AFB1会引起部分肝细胞出现轻微萎缩、肝细胞核移位、细胞界限模糊和肝细胞内空泡化的现象。研究表明,在本实验条件下,饲料中AFB1含量低于200μg/kg不影响黄颡鱼幼鱼生长性能,但饲料中AFB1≥50μg/kg时会影响黄颡鱼幼鱼肠道的消化吸收功能,同时引起肝脏氧化应激及炎性反应,造成肝脏功能损伤。  相似文献   

10.
根据2010-2011年和2015-2016年对长江天鹅洲故道鱼类资源的调查,分析了长江天鹅洲故道鱼类种类组成、优势种和物种多样性的变化,着重了解长江江豚(Neophocaena asiaeorientalis asiaeorientalis)潜在饵料鱼资源-小型鱼类的情况。结果表明,2次调查共采集到鱼类51种,隶属于6目12科41属,其中2010-2011年采集鱼类50种,2015-2016年采集鱼类38种。小型鱼类共采集到32种,其中2010-2011年度为31种,2015-2016年度为22种,减少的种类主要为长江干流繁殖进入天鹅洲故道的种类。2015-2016年相比2010-2011年,小型鱼类优势种也发生了较大的改变,2010-2011年故道小型鱼类优势种5种,按优势度大小排序为:短颌鲚(Coilia brachygnathus)、贝氏歺又鱼(Hemiculter bleekeri)、鲫(Carassius auratus)、似鳊(Pseudobrama simoni)和银鮈(Squalidus argentatus);而2015-2016年优势种为4种,按优势度大小排序为:黄尾鲴(Xenocypris davidi)、歺又鱼(Hemiculter leucisculus)、短颌鲚和鲫,来自长江干流繁殖的小型鱼类资源有所减少。建议通过灌江纳苗引入似鳊、银鮈、贝氏歺又鱼等长江干流繁殖的小型鱼类,改善生境,为歺又鱼、鲫等湖泊定居鱼类提供良好的繁殖环境,以增加长江江豚饵料鱼类的资源量,满足其食物需求。  相似文献   

11.
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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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.
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   

16.
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   

17.
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   

18.
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   

19.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future.  相似文献   

20.
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos.  相似文献   

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