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复合酶制剂对黄颡鱼生长性能、血清生化和免疫指标的影响 总被引：4，自引：0，他引：4
选取360尾初始体质量约为2.48 g的黄颡鱼(Pelteobagrus fulvidraco)幼鱼,随机分为4组,分别投喂添加0(对照)、100 mg·kg-1、200 mg·kg-1和400 mg·kg-1复合酶制剂的试验饲料,养殖8周。结果表明,黄颡鱼的增重率、特定生长率和摄食量随复合酶制剂添加量的增加而升高,其中400 mg·kg-1组的增重率、特定生长率和摄食量分别比对照组高出15.4%、7.5%和20.3%(P<0.05)。各组黄颡鱼的粗蛋白质、粗脂肪、水分和灰分质量分数差异不显著(P>0.05)。随着复合酶制剂水平的增加,血清尿素浓度逐渐降低,血清谷丙转氨酶、谷草转氨酶活力和总蛋白质量浓度升高,血清溶菌酶活力则先升高后降低,在100~200 mg·kg-1时有最高值(P<0.05);血清超氧化物歧化酶活力和丙二醛质量摩尔浓度均无显著性差异(P>0.05)。饲料中添加400 mg·kg-1复合酶制剂能显著提高黄颡鱼的生长性能和血清谷丙转氨酶活力,降低血清尿素水平;200 mg·kg-1能显著提高血清总蛋白质量浓度、谷草转氨酶和溶菌酶活力。 相似文献
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为了探讨三氯生(TCS)对雌性鱼类性激素的影响及其机制。通过半静态水质接触染毒法对雌性黄河鲤进行染毒,设置对照组和三个不同浓度组(0.04 mg/L、0.08 mg/L、0.16 mg/L)的TCS处理组,采用酶联免疫(ELISA)和实时荧光定量PCR(RT-PCR)法检测各组雌性黄河鲤血清睾酮(T)和雌二醇(E2)的分泌水平及其卵巢中促性腺激素释放激素(CGnRH-ii-2)和雌激素受体(Er)的mRNA表达水平。结果显示：各浓度组的T水平无显著性差异(P>0.01),而0.16 mg/L的TCS能使黄河鲤血清中的E2含量及E2/T显著性升高(P<0.05, P<0.01);TCS各浓度组卵巢中CGnRH-ii-2 mRNA水平显著下降(P<0.01),而0.08和0.16mg/L的TCS处理组Er mRNA水平显著升高(P<0.05,P<0.01)。结果表明：TCS具有潜在雌激素效应,其机制与雌激素受体和促性腺激素释放激素基因表达调控相关。 相似文献
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低浓度甲基汞对鲤鱼生长及生理生化指标的影响 总被引：1，自引：0，他引：1
水体甲基汞（浓度10μg／L）染毒鲤鱼（秋片）,一个月内汞处理鱼出现增重均6％,继续染毒2个月生长受到抑制。毒性实验结果表明：此剂量染毒一个月的鲤鱼血浆渗透压、血糖、和甲状腺激素T3含量与对照组鱼相比均未见显著差异。仅鳃丝线粒体Na+－K+－ATPasc活性在染毒2周时出现下降（P＜O．05）。染毒一个月时,汞染毒鱼的血浆某些离子浓度出现变化：血浆Na+明显降低（P＜0．01）,血浆K+和Mg2+升高,PO和CI-下降值分别出现在21天和7天的染毒鲤鱼（P＜0．05）。病理组织切片观察：肝组织边缘个别细胞体积增大,细胞变圆形。 相似文献
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在低盐度5~6和水温25~29℃条件下,分别投喂1种对照饲料和7种添加二甲基-β-丙酸噻亭(DMPT)(添加量分别为100、2003、00、400、5006、00和700mg.kg-1)的试验饲料,饲养初始体重约每尾0.77g的凡纳滨对虾56d,观察DMPT对凡纳滨对虾的生长、蜕壳和渗透压调节的影响。实验结果表明,添加DMPT的各组凡纳滨对虾增重率随着DMPT添加量的增加,呈现先升后降的趋势,在400mg.kg-1凡纳滨对虾增重率达到最高,显著高于对照组;与对照组相比,各试验组凡纳滨对虾的饲料系数均不同程度降低,500mg.kg-1DMPT组凡纳滨对虾的饲料系数降低达到显著水平。添加DMPT对凡纳滨对虾的蜕壳次数无显著影响。除100mg.kg-1DMPT组外,DMPT组凡纳滨对虾的渗透压均明显低于对照组,其中,添加300和500mg.kg-1组凡纳滨对虾的渗透压降低呈现显著性差异。凡纳滨对虾肌肉粗蛋白和粗脂肪含量随着DMPT水平增加呈现出先上升后下降的趋势。粗蛋白含量在DMPT添加量为400mg.kg-1时达到最高,粗脂肪含量在DMPT添加量为600mg.kg-1时达到最高,均显著高于对照组。以增重率为判定指标,DMPT在凡纳滨对虾饲料中的适宜添加量为383mg.kg-1。 相似文献
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镉对金鱼性激素的分泌及某些生理生化效应的研究 总被引：4，自引：0，他引：4
镉浓度40（mg/l）染毒金鱼10、20、35天的实验结果表明：镉引起了染毒鱼的雌二醇和睾酮增高。甲状腺激素（T3）含量仅在染毒10天时增高（P＜0．05），尔后变化不明显。此外，染毒鱼和血浆离子Mg^2 浓度和血糖均升高（20天），其他离子K^ 、Na^ 无明显变化。测试生长指标表明：此剂量镉对金鱼的生长在染毒20天时无抑制作用。染毒35天时，染毒鱼倾向于负生长。 相似文献
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试验以硫酸锌为锌源,评价不同锌水平对奥尼罗非鱼幼鱼(Oreochrvmis aureus ♂×Oreochromis niloticus♂)生长和抗氧化能力的影响.体质量为(4.13±0.32)g罗非鱼随机分配在18个水族箱中,每箱20尾,每3个箱为1个处理组,分别以添加锌为0、20、40、80、160和320 mg·kg-1的6种饲料投喂,日投喂率为鱼体重5%～9%.8周的试验结果表明:20 mg·kg-1锌饲料组的增重率和鱼体蛋白含量显著高于其它各组(P<0.05),蛋白质效率、饲料转化率也明显高于其它各组;全鱼脂肪含量随着饲料锌水平的升高而升高,但320 mg·kg-1锌饲料组降低;20 mg·kg-1锌饲料组,脊椎骨中锌离子浓度达到最大值且显著高于0 mg·kg-1锌饲料组(P<0.05);20 mg·kg-1与40 mg·kg-1锌饲料组的血液中红细胞数量显著高于其它各添加组(P<0.05),20 mg·kg-1锌饲料组的血液中血比容显著高于0 mg·kg-1组(P<0.05),与其它各组没有显著差异;肌肉中,硫代巴比妥酸反应产物(TBARS)(Thiobarbituricacid-reactivesubstances)的量,锌为0mg·kg-1饲料组显著高于其它各组(P<0.05).综上所述,饲料中锌添加量为20 mg·kg-1饲料促进了罗非鱼生长,使鱼体抗氧化功能增强. 相似文献
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《水产科学》2021,(1)
水温12～18℃,将体质量(435.63±21.32) g的哲罗鲑饲养在6.0 m×2.5 m×1.2 m的流水水泥池中,投喂含100 mg/kg人工合成虾青素(对照组)和10、20、40、60 mg/kg天然虾青素(雨生红球藻)饲料,每两周检测试验鱼肌肉中的虾青素含量和鳃、肝脏、前肠、后肠、幽门垂、肌肉、血清、血细胞的总抗氧化能力和碱性磷酸酶活性,研究人工合成虾青素和天然虾青素对肌肉中虾青素含量及其组织抗氧化力的影响。70 d的饲养结果显示:(1)与对照组相比,20 mg/kg和40 mg/kg组的试验鱼虾青素含量显著升高(P0.05),且40 mg/kg含量组试验鱼虾青素含量显著优于20 mg/kg组(P0.05);(2)各组试验鱼鳃、肝脏、前肠、后肠、幽门垂、血清、血细胞的总抗氧化能力显著高于对照组(P0.05);(3)各组试验鱼鳃、后肠、幽门垂、肌肉、血清、血细胞的碱性磷酸酶活性显著高于对照组(P0.05)。试验结果表明,与添加100 mg/kg人工合成虾青素相比,饲料中添加20～40 mg/kg天然虾青素,能显著提高哲罗鲑肌肉虾青素含量、总抗氧化能力以及碱性磷酸酶活性,建议哲罗鲑饲料中天然虾青素添加量为40 mg/kg。 相似文献
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为了解三氯生(TCS)对去染毒后恢复期红白鲫不同机体组织抗氧化系统的影响,设置了对照组和TCS染毒组(质量浓度为0.139 mg/L),对试验鱼先染毒14 d,然后去染毒7 d进行恢复,恢复后测定对照组和染毒组红白鲫鳃、肌肉和肝胰脏等组织中丙二醛(MDA)、还原型谷胱甘肽(GSH)的含量和总抗氧化能力(T-AOC)。结果显示:染毒组红白鲫鳃、肌肉和肝胰脏的MDA含量与对照组均无显著差异(P0.05);染毒组红白鲫肌肉和肝胰脏的GSH含量与对照组也无显著差异(P0.05),但鳃中GSH的含量显著低于对照组(P0.05),且鳃中T-AOC显著低于对照组(P0.05)。研究表明,相对于肌肉和肝胰脏,TCS对红白鲫鳃组织的抗氧化系统能产生显著且具有持续性的影响。 相似文献
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为研究蛋氨酸铬对鲤血清生化指标和非特异性免疫指标的影响,配制蛋氨酸铬添加水平分别为0、0.1、0.2、0.4、0.8、1.6、3.2 mg/kg的7种饲料,选取初始体质量为(40.95±4.80)g的鲤1 260尾,进行了为期8周的饲养试验。结果表明:(1)添加0.4 mg/kg蛋氨酸铬的试验组,其胆固醇(TC)、甘油三脂(TG)含量最低,与其它组差异显著(P0.05);添加1.6 mg/kg的组,其高密度脂蛋白(HDL)含量最高;添加0.8mg/kg的组,其低密度脂蛋白(LDL)显著高于对照组(P0.05)。添加0.4~3.2 mg/kg蛋氨酸铬的试验组,鲤血清中的谷草转氨酶(GOT)活性高于对照组(P0.05)。(2)添加蛋氨酸铬的试验组,鲤肝胰脏中超氧化物歧化酶(SOD)的活性均高于对照组;0.8 mg/kg添加组的总抗氧化能力(T-AOC)和过氧化氢酶(CAT)活性均显著高于对照组(P0.05);0.4 mg/kg添加组的丙二酮(MDA)含量低于其它各组。添加0.2~3.2 mg/kg蛋氨酸铬的试验组,其AKP活性显著低于对照组(P0.05);鲤肝胰脏中谷草转氨酶(GOT)的活性随着蛋氨酸铬添加量的增加呈现上升趋势,且均显著高于对照组(P0.05);除3.2 mg/kg添加组外,其它各组的谷丙转氨酶(GPT)活性均显著下降。综上所述,在饲料中添加0.4~0.8 mg/kg的蛋氨酸铬能够增强鲤肝胰脏的非特异性免疫力。 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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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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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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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
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
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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
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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
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Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献
20.
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