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21.
采用剪标记法,现场模拟测定了钻井噪声与振动对鲤鱼生长的影响,研究结果表明,钻井噪声与振动对鲁鱼生长有显著影响,其临界等效噪声级和振动级约为83.9dB和89.7dB,影响域径约为9m,污染持续时间,体重和群居行为等生态因素,能显著改变钻井噪声与振动对鲤鱼生长的污染效应,由在污染消失后鲤鱼生长率能迅速恢复,这说明钻井噪声与振动鲤鱼的生长的污染效应,由于在污染消失后鲤鱼生长率能迅速恢复,这说明钻井噪声与振动对鲤鱼的影响机制可能是合理的。  相似文献   
22.
喹乙醇诱导鲤肝细胞凋亡的研究   总被引:6,自引:0,他引:6  
汪开毓 《水产学报》2004,28(6):733-737
细胞凋亡(apoptosis)是受基因控制的细胞自主的有序死亡。凋亡细胞的形态特征主要表现为细胞核的染色质浓缩,边移,聚集在核膜下,进而核发生裂解,核碎片与细胞碎片有单层膜包裹形成凋亡小体(apoptosisbody)[1]。目前已发现某些物理因素(辐射、高温等)、细胞因子、病毒感染和  相似文献   
23.
The growth of two breeds of common carp, Cyprinus carpio L., was tested in ponds under the climatic conditions of South Bohemia. T?eboň scaly carp (TR) and Hungarian mirror carp (M2) were kept in both low and high stocking densities during the second growing season and then stocked together for communal testing during the third growing season. Before the communal testing, the mean initial weights of fish from low‐ and high‐density stocks differed significantly (374.1 vs. 227.7 g for the TR breed and 766.7 vs. 317.3 g for the M2 breed respectively, P<0.01). After communal testing, mean weights of fish from low‐ and high‐density stocks gained 761.8 vs. 543.8 g for the TR breed and 1339.7 vs. 706.7 g for the M2 breed respectively. These observed weights were also significantly different (P<0.01). However, the test of corrected weight gain, i.e. gain not related to the initial weight of fish, revealed insignificant differences (P>0.01) between the weight gains after correction, i.e. the effect of different initial weights was successfully eliminated. These results seem to confirm the applicability of this method for the assessment of growth of purebred common carp under the climatic conditions of Central European fish farms.  相似文献   
24.
Koi carp and goldfish value increases with intensity of skin colour, which is an important quality criterion. Fish cannot fully synthesize their own carotenoid colourings and these must therefore be included in their diet. Two trials were undertaken to investigate skin colour enhancement in ornamental species (i.e. three chromatic varieties of koi carp (Cyprinus carpio), namely Kawari (red), Showa (black and red) and Bekko (black and white) and goldfish (Carassius auratus)) by feeding a dietary carotenoid supplement of freshwater microalgal biomass [Chlorella vulgaris, Haematococcus pluvialis, and also the cyanobacterium Arthrospira maxima (Spirulina)], using a diet containing synthetic astaxanthin and a control diet with no colouring added for comparison. In the first trial, five homogeneous duplicate groups of 25 juvenile koi carp (C. carpio) (initial mean body weight 24.6 ± 0.7 g) were fed, for 10 weeks, one of the four diets containing 80 mg colouring/kg diet. In the second trial, this procedure was repeated for five homogeneous duplicate groups of 25 goldfish (C. auratus) (initial mean body weight of 0.9 ± 0.1 g). Initial and final samples of skin along the dorsal fin were withdrawn, from five fish per group, for subsequent analysis of total carotenoid content (spectrophotometric analysis), and red hue (colorimetric analysis, CIE (1976) L* a* b* colour system). Growth and feed efficiency were not significantly different between groups administered by the various dietary treatments. In both trials, dietary carotenoid supplementation increased total skin carotenoid content. The more efficient colouring for koi carps was found to be C. vulgaris biomass, providing both maximum total carotenoid deposition and red hue for the three chromatic koi carp varieties studied, and particularly for the kawari variety. For goldfish the best colouring obtained, as ascertained by total carotenoid content, was also achieved using C. vulgaris biomass, and red hue was maximum when using H. pluvialis biomass.  相似文献   
25.
采用聚丙烯酰胺凝胶电泳技术,分析了鲤鱼性成熟期雌雄个体的血清蛋白、血清脂蛋白和血红蛋白,结果是雌雄个体血清蛋白电泳图谱有差异,雌性(14条)比雄性(13条)多1条蛋白带;血清脂蛋白和血红蛋白无性别差异。同时,测定了鲤鱼血清、肝胰脏、心脏、背部肌肉和眼晶体的乳酸脱氢酶(LDH)同工酶和酯酶(EST)同工酶,LDH具有组织特异性,除在肝胰脏分离出9条酶带外,在血清中也分离出8条酶带,表明有LDH—c基因的作用,EST同工酶表现出明显的多态性,表明在鲤鱼各组织中有多个基因座位起作用。  相似文献   
26.
To compare the effect of polyculture against conventional monoculture on ornamental carp production, investigations on food selection and growth performance of koi carp (K), Cyprinus carpio L. and goldfish (G), Carassius auratus (L.) were conducted in a 11‐week rearing experiment in two monoculture (100% K and 100% G) and five polyculture (90% K–10% G, 70% K–30% G, 50% K–50% G, 30% K–70% G and 10% K–90% G) conditions in tropical ponds. There were three replicates for each treatment. Environmental conditions and food availability were similar in all the treatments. Ivlev's electivity index showed that both fish species avoided phytoplankton and preferred cladocerans to other zooplankton groups (copepods and rotifers) in monotypic conditions. However, in the polyculture treatments, the positive electivity of goldfish towards cladocerans reduced significantly (P<0.05), while the percentage of copepods, rotifers and phytoplankton in the gut content increased. No significant differences in weight gain, specific growth rate and deformities were recorded at harvest for koi carp between the different treatments (P>0.05). Even the survival rate of koi carp recorded above 90% in all the treatments. However, the goldfish recorded significantly better weight gain, specific growth rate and survival in monoculture (100% G), compared with the polyculture treatments (P<0.05). Goldfish deformities were lowest (P<0.05) in the monoculture treatment (2.42%). The number of marketable fish above a set size limit of 4 g total weight was significantly higher in the two monoculture treatments, compared with the five polyculture treatments (P<0.05). Keeping in view of the dietary similarities of koi carp and goldfish, and the aggressive nature of koi carp in polyculture, it is suggested to refrain from polyculture of goldfish and koi carp until further documentations relating to optimum stocking density and management of polyculture of ornamental carps are available.  相似文献   
27.
28.
殷国俊 《水产学报》2004,28(6):628-632
用密度梯度离心分离鲤头肾中的巨噬细胞和嗜中性粒细胞。用RPMI细胞培养液对分离的细胞进行原代培养,在细胞培养液中加入不同浓度的黄芪水提取液来研究黄芪对鲤头肾中免疫细胞非特异性免疫应答的影响。黄芪水提取液单独使用时能刺激鲤头肾中巨噬细胞的增殖,但不能刺激巨噬细胞的氮暴发活性。用黄芪和脂多糖(LPS)混合刺激巨噬细胞和中性粒细胞时,黄芪水提取液能显著提高脂多糖刺激所产生的一氧化氮的产量。研究结果表明,黄芪不仅能刺激巨噬细胞数量的增加,而且能协同脂多糖增强头肾中免疫细胞的功能,从而对机体的非特异性免疫起调节作用。  相似文献   
29.
ABSTRACT:   The thermal stability of carp G-actin was investigated by monitoring loss of actin polymerization ability. To determine the amount of native actin remaining after heat treatment, actin was labeled with a fluorescence reagent, N-(1-pyrene)iodoacetamide. The loss of polymerization ability of carp actin during heat treatment, at between 45 and 55°C, occurred faster than that of chicken actin. The inactivation rate was influenced by concentrations of ATP and Ca2+ in solution. With the increase of Ca2+ concentration, the inactivation of carp actin was markedly suppressed. Furthermore, the activation energy of the inactivation of carp actin obtained from an Arrhenius plot was similar to that of chicken actin. These results indicated that the thermal instability of carp G-actin was due to the low affinites of ATP and Ca2+ for carp actin described in a previous report.  相似文献   
30.
China and Hungary are major providers of the common carp (Cyprinus carpio L.) in East Asia and Europe respectively. However, the genetic variation and relationship of this species in the two countries have been poorly understood. In this study, mitochondrial COII‐tRNALys and D‐loop sequences were analysed to investigate the genetic structure and relationships of the representative wild and domesticated common carps distributed in China and Hungary. The results indicated that the genetic diversities of the Chinese common carps are higher than those of Hungarian common carps, and the diversities of the wild common carps are higher than those of domesticated common carps in both the countries. Analysis of molecular variance and pairwise FST demonstrated a significant genetic divergence between the Chinese and the Hungarian common carps, and between the wild and the domesticated common carps. Bayesian phylogenetic analysis and statistical parsimony network showed an obvious genetic differentiation between the Chinese and the Hungarian common carps, between the wild and the domesticated common carps. However, a few specimens and haplotypes from the Chinese wild common carps appeared in the Hungarian common carps, demonstrating that there was no absolutely isolated and possible genetic linker between the Chinese and the Hungarian common carps.  相似文献   
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