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研究鱼类的游泳运动对于指导实际生产具有重要的参考价值。本试验通过自制游泳装置来研究在不同体质量(10、15、20和25 g)和不同温度(12、16、20、24和28℃)下幼鱼的游泳能力及行为,并探讨在0.12、0.24、0.36和0.48 m/s流速下的幼鱼随时长的代谢情况。结果显示:4个规格幼鱼的临界游泳速度(UC)分别为0.42±0.03、0.47±0.01、0.53±0.03和0.62±0.01m/s,爆发游泳速度(UB)分别为0.53±0.06、0.56±0.02、0.60±0.02和0.72±0.01 m/s。幼鱼UC和UB随体质量增加游泳能力显著提高。5个温度组下25 g幼鱼的UC和UB随温度的升高呈上升后下降趋势,24℃时UC和UB达到最大值且与其他组差异显著(P<0.05)。随着流速的增加尾鳍、背鳍和臀鳍的摆动频率不断加快,摆尾频率的4个流速组之间差异显著(P<0.05),背鳍和臀鳍的... 相似文献
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探讨了温度、盐度对褐牙鲆(♀)×犬齿牙鲆(♂)杂交子一代(杂交F1)胚胎和初孵仔鱼发育的影响。结果表明,杂交F1受精卵孵化适宜温度范围和最适温度分别为15~21℃和18℃,在适宜温度范围内胚胎发育时间随温度的升高而缩短,二者符合乘幂函数关系式N=115.99T^-0.768.8(R^2=0.9769)。胚胎发育的生物学零度和有效积温分别是7.54℃和540.1℃·h,积算温度(A)与试验水温间呈乘幂函数相关,表达式:A=1328.1T^-0.3149。(R^2=0.9624)。胚胎发育的最低盐度界限为10,孵化的适宜盐度范围和最适盐度范围分别为10~45、25~35;初孵仔鱼生存发育的适宜盐度范围、最适盐唐范围分别为10~40和10~20。 相似文献
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为研究低氧胁迫对鲻幼鱼生长、能量代谢和氧化应激的影响,实验将其放在溶解氧(DO,mean±SE)含量分别控制在(1.66±0.41)、(4.35±0.53)、(7.03±0.36)mg/L的条件下养殖10 d,然后恢复至接近饱和溶解氧含量7.0 mg/L的条件下养殖30 d,研究其特定生长率、排氨率、耗氧率、氧氮比和血浆、肌肉、肝脏及鳃组织的总抗氧化能力(T-AOC)、过氧化物歧化酶(SOD)活力、抗超氧阴离子活力(ASOR)、丙二醛(MDA)含量、乳酸(LD)含量、总谷胱甘肽(T-GSH)、还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)含量。结果表明:低氧胁迫对鲻幼鱼的生长、能量代谢影响显著,较严重缺氧组鲻的体质量、特定生长率(SGR)、耗氧率和排氨率显著低于其他处理,不具有补偿生长的能力;而轻微缺氧组获得完全补偿生长。低氧胁迫对鲻氧化应激指标影响显著,胁迫结束时鲻通过提高某些抗氧化酶的活力来增强抗氧化能力,以提高其应对恢复正常溶解氧环境可能带来的氧化应激的能力,同时在恢复溶氧后鲻氧化应激反应也较强烈。在恢复溶解氧阶段,肝脏中GSH显著增加,说明鲻体内的保护机制被激活。肝脏和鳃中MDA的含量在低氧胁迫后与溶解氧含量呈明显的负相关性,在复氧30 d后仍然高于对照组,表明低氧胁迫加强鲻肝脏和鳃组织脂质过氧化反应。 相似文献
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本文报导了细鳟鱼(Braochymystax enok P.)体长与体重的关系、最大日摄入能与生长能的关系、生态生长效率等方面生长与能量代谢的研究结果。并确定养殖中最低投饵水平,对生产有一定的指导作用。 相似文献
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Dahai Zheng Kangsen Mai Shuqing Liu Limin Cao Zhiguo Liufu Wei Xu Beiping Tan & Wenbing Zhang 《Aquaculture Research》2004,35(5):494-500
Experiments were designed to determine the effects of temperature and salinity on the virulence of Edwardsiella tarda to Japanese flounder, Paralichthys olivaceus. In the temperature experiment, a two‐factor design was conducted to evaluate the effects of both pathogen incubation temperature and fish cultivation temperature on pathogen virulence. E. tarda was incubated at 15, 20, 25 and 30±1°C, and the fish (mean weight: 10 g) were reared at 15, 20 and 25±1°C respectively. The fish reared at different temperatures were infected with the E. tarda incubated at different temperatures. The results of a 4‐day LD50 test showed that temperature significantly affected the virulence of E. tarda (P<0.01) and the interaction between the two factors was also significant (P<0.01). For fish reared at 15°C the virulence of E. tarda was the highest at 25°C of pathogen incubation, followed by 20, 15 and 30°C. When the fish rearing temperature was raised to 20 and 25°C, the virulence of E. tarda incubated at all temperatures increased. Isolation testing demonstrated results similar to those of LD50. The higher rearing temperature increased the proliferation rate of the pathogen in fish. In the salinity experiment, the incubation salinity of E. tarda was at 0, 10, 20 and 30 g L?1, respectively, and the fish with mean weight of 50 g were cultured in natural seawater of 30 g L?1. The results of one‐way anova in 4‐day LD50 test showed that incubation salinity significantly affected virulence. Virulence was lower when the salinity of the incubation medium was at 0 and 30 g L?1, higher at 10 and 20 g L?1. The results of isolation test were in accordance with those of LD50. At 20 g L?1E. tarda had a faster proliferation rate than that at 10 g L?1. 相似文献
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为分析牙鲆(Paralichthys olivaceus)体质量与形态性状之间异速生长的遗传规律,通过人工受精的方法建立牙鲆19个全同胞家系,测量了牙鲆不同日龄的体质量和形态性状。采用逐步回归方法建立最优联合异速生长模型,将此模型镶嵌到体质量动物模型的每个遗传和环境效应中,进一步分析对多个形态性状异速生长遗传规律。静态异速生长分析表明:体质量与全长之间存在最大异速生长指数(1.415 5),表现为正异速生长,剩余形态性状与体质量之间的异速生长指数为0.061 5~0.718 0,皆表现为负异速生长。全长与尾柄高之间异速生长指数的正遗传相关最大(0.907 8);全长与尾柄长之间的负遗传相关最大(0.946 8)。不同模型通过统计标准比较,确定模型Ⅰ为进行牙鲆动态异速生长分析的最优随机回归模型。 相似文献
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在水温为20.0±0.5℃条件下,研究了不同盐度(0、3.0、6.0、9.0、12.0)和不同体重(平均体重为7~8 g、19~20 g两种规格)对克氏原螯虾的耗氧率、CO2排出率以及NH3-N排泄率的影响。结果表明,低盐度条件下(0~6.0),两种规格克氏原螯虾的耗氧率、CO2排出率和NH3-N排泄率均随着盐度的升高而显著上升(P<0.05),盐度为6的条件下代谢水平达最高值,此后随着盐度的升高耗氧率、CO2排出率和NH3-N排泄率显著下降(P<0.05);相同盐度下,小规格(平均体重为7~8 g)克氏原螯虾的耗氧率、CO2和NH3-N排泄率显著高于大规格虾(平均体重为19~20 g)。相同规格的克氏原螯虾在不同盐度条件下呼吸商、氧氮比均无显著差异(P>0.05),但是大规格的克氏原螯虾呼吸商和氧氮比显著大于小规格的虾(P<0.05),前者的代谢率极显著低于后者(P<0.01)。 相似文献
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An energetic method was used to investigate the effects of stocking density and dissolved oxygen (DO) concentration on the growth of juvenile Paralichthys olivaceus. Fish, with initial weights of 14±2.1 g, were exposed to a normal and a high DO of 5.5±0.5 and 14±2 mg L?1, as well as four stocking densities per DO concentration (100, 200, 300 and 400 ind m?2 for the normal DO and 200, 400, 600 and 800 ind m?2 for the high DO). The feed efficiency (FEW) decreased significantly with increasing stocking density and increased significantly with increasing DO concentration. The maximum weight was achieved at 400 ind m?2 under a high DO depending on our rearing conditions. The stocking density and DO concentration change energy ingestion and its allocation for respiration, growth and excretion lost in nitrogen excretion, but do not affect the energy loss through faeces. The results of the body composition of fish indicated that the stocking density and DO concentration had no significant effects on the moisture, lipid content and gross energy, but are affected by the same. Energetic analysis demonstrated that high DO concentrations could alleviate the growth depression caused by high stocking densities, decrease energy loss in respiration and nitrogen excretion and increase the energy proportion allocated to growth. 相似文献
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牙鲆家系4 个选育性状的测定与分析 总被引:2,自引:1,他引:1
为了研究牙鲆(Paralichthys olivaceus)不同选育性状之间的相关性,2009年建立了38个牙鲆实验家系和1个养殖场对照组。选取其中33个家系和对照组进行鳗弧菌感染实验并对存活个体进行荧光标记后混合养殖在2个水泥池中,其中一个混养池在平均400日龄时暴发了淋巴囊肿病(Lymphocystis Disease,LD),LD发病率为62.4%,包括16个家系和对照组。从这些家系中筛选出4个发病率低于40.0%的抗病家系(F0939,F09104,F0915,F0908)。另外,在4~5月龄时,从每个家系中平均选取100尾鱼进行荧光标记后混合养殖,580日龄时测定这些家系的养殖存活率和体重,平均养殖存活率为32.0%,将7个养殖存活率高于55.0%的家系定义为高养殖存活率家系(F0908,F0975,F0990,F09125,F0927,F09119,F0905)。对牙鲆LD的抗病个体和易感个体的体重和全长进行卡方检验,发现抗病个体的体重和全长均显著高于易感个体(P0.01),同时分析牙鲆各个家系的LD发病率与发病时的体重和全长的相关性,结果显示牙鲆各个家系LD发病率与发病时体重和全长均呈强负相关(r–0.6)。对牙鲆家系鳗弧菌感染存活率、LD发病率、580日龄的养殖存活率和体重这4个性状两两之间进行相关性分析,发现LD发病率与580日龄的体重呈强负相关(r=–0.790);鳗弧菌感染存活率与养殖存活率之间为弱正相关(r=0.371);其他性状两两之间不存在显著相关性(–0.092≤r≤0.185)。本研究共筛选到了4个牙鲆LD抗病家系和7个高养殖存活率家系,并揭示了4个牙鲆选育性状之间的相关性,为培育速生多抗的牙鲆新品种提供了遗传材料和理论依据。 相似文献
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Two feeding trials were carried out to determine the optimum feeding rates in juvenile olive flounder, Paralichthys olivaceus, at the optimum rearing temperature. Fish averaging 5.0 ± 0.11 g (mean ± SD) in experiment 1 and 20.2 ± 0.54 g (mean ± SD) in experiment 2 were fed a commercial diet at the feeding rates of 0%, 3.0%, 4.0%, 4.25%, 4.5% and 4.75% body weight (BW) day?1 and satiation (5.52% BW day?1) in experiment 1 and 0%, 1.0%, 2.0%, 3.0% and 3.5% BW day?1 and satiation (4.12% BW day?1) in experiment 2 at 20 ± 1 °C. Both feeding trials lasted for 2 weeks. Results from experiment 1 indicated that weight gain (WG) and specific growth rate (SGR) of fish fed to satiation were significantly higher than those of fish fed at other feeding rates while feed efficiency (FE) and protein efficiency ratio (PER) of fish fed at 4.25% BW day?1 were significantly higher than those of fish fed to satiation and fish fed at 3.0% BW day?1 (P < 0.05). In experiment 2 WG, SGR and PER leveled out after the feeding rate of 3.5% BW day?1 whereas FE reached a plateau at 3.0% BW day?1. anova of FE indicated that the optimum feeding rates in 5.0 and 20 g juvenile olive flounder could be 4.25% and 3.0% BW day?1, respectively. Broken line analysis of WG suggested the optimum feeding rates of 5.17% and 3.47% BW day?1 in 5.0 and 20 g fish, respectively. Therefore, these results indicated that the optimum feeding rates could be >4.25 but <5.17% BW day?1 for 5.0 g, and it could be >3.0 but <3.47% BW day?1 for 20 g size of juvenile olive flounder at the optimum rearing temperature. 相似文献
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鱼类的能源物质以蛋白质和脂肪为主,但在鱼体内蛋白质代谢的最终产物以氮排泄物形式通过鳃排出体外,少量随尿排出,氮排泄的主要成分为氨和尿素,仅有少量用于生长.本实验采用鱼类生物能量学的方法,在保持最大摄食率水平的条件下,通过四个不同梯度蛋白质对牙鲆个体的能量转换进行了研究,从而探讨牙鲆的最适蛋白水平,结果表明:当牙鲆投喂蛋... 相似文献
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The cytological process of induced gynogenetic development and subsequent chromosome duplication by a cold shock treatment was observed in Japanese flounder Paralichthys olivaceus (Temminck et Schlegel). Mature eggs were at the metaphase of the second meiosis when inseminated with ultraviolet (UV)-irradiated sperm of red sea bream Pagrus major . After the beginning of cold shock treatment, the previously visible spindle became invisible, probably due to the side effect caused by cold shock treatment. The chromosomes at the centre of the metaphase plate were condensed. This condition continued during the duration of the cold shock treatment and several minutes after it. The release of the second polar body was blocked and it developed into a female-like pronucleus. Then, it fused with the female pronucleus to generate a diploid zygotic nucleus, and the egg exhibited the first mitosis. Consequently, the haploid female chromosome set of the egg was doubled by the inhibition of the second polar body release. There was a significant delay in developmental time in the gynogenetic eggs when compared with that in the normal eggs. From the time of insemination to early cleavage, the UV-irradiated heterospecific sperm nucleus remained condensed. 相似文献