两种微生态调节剂对网箱鲤鱼生产效果的影响

两种微生态调节剂（ＭｉｃｒｏｂｅＦＡ９１０２和一种芽胞杆菌制剂）添加到基础饵料中用于网箱鲤鱼的饲养试验。ＭｉｃｒｏｂｅＦＡ９１０２试验组和对照组鲤鱼在增重及饲料利用率方面无显著差异,但ＭｉｃｒｏｂｅＦＡ９１０２可取代部分蛋白饲料和降低生产成本,而芽胞杆菌制剂似乎不宜用于鲤鱼生产。因而进一步筛选适用于红鱼生长的理想的微生态制剂仍是必要的。     

Expression of titin isoforms in red and white muscle fibres of carp (Cyprinus carpio L.) exposed to different sarcomere strains during swimming

Titin (also known as connectin) is a striated-muscle-specific protein that spans the distance between the Z- and M-lines of the sarcomere. The elastic segment of the titin molecule in the I-band is thought to be responsible for developing passive tension and for maintaining the central position of thick filaments in contracting sarcomeres. Different muscle types express isoforms of titin that differ in their molecular mass. To help to elucidate the relation between the occurrence of titin isoforms and the functional properties of different fibre types, we investigated the presence of different titin isoforms in red and white fibres of the axial muscles of carp. Gel electrophoresis of single fibres revealed that the molecular mass of titin was larger in red than in white fibres. Fibres from anterior and posterior axial muscles were also compared. For both white and red fibres the molecular mass of titin in posterior muscle fibres was larger than in anterior muscle fibres. Thus, the same fibre type can express different titin isoforms depending on its location along the body axis. The contribution of titin to passive tension and stiffness of red anterior and posterior fibres was also determined. Single fibres were skinned and the sarcomere length dependencies of passive tension and passive stiffness were determined. Measurements were made before and after extracting thin and thick filaments using relaxing solutions with 0.6 mol · l⁻¹ KCl and 1 mol · l⁻¹ KI. Tension and stiffness measured before extraction were assumed to result from both titin and intermediate filaments, and tension after extraction from only intermediate filaments. Compared to mammalian skeletal muscle, intermediate filaments developed high levels of tension and stiffness in both posterior and anterior fibres. The passive tension-sarcomere length curve of titin increased more steeply in red anterior fibres than in red posterior fibres and the curve reached a plateau at a shorter sarcomere length. Thus, the smaller titin isoform of anterior fibres results in more passive tension and stiffness for a given sarcomere strain. During continuous swimming, red fibres are exposed to larger changes in sarcomere strain than white fibres, and posterior fibres to larger changes in strain than anterior fibres. We propose that sarcomere strain is one of the functional parameters that modulates the expression of different titin isoforms in axial muscle fibres of carp. Accepted: 7 May 1997     

Toxicity of Tributyltin in Juvenile Common Carp (Cyprinus Carpio): Physiological Responses,Hepatic Gene Expression,and Stress Protein Profiling

In this study, the effects of tributyltin (TBT) on biochemical parameters (antioxidant responses and Na⁺‐K⁺‐ATPase) in different tissues were investigated by using juvenile common carp (Cyprinus Carpio) as well as growth and ion regulation–related genes expression and stress‐related proteins profiling in fish liver. Oxidative stress indices and Na⁺‐K⁺‐ATPase showed tissues‐specific responses in fish exposed to different TBT concentrations. All tested genes related to GH/IGF‐I axis and ion‐regulation were significantly induced in the TBT group with lower concentrations (except for the igfbp3 in 10 μg/L) and were inhibited in 20 μg/L. In addition, the profiling of two proteins Hsp 70 and MT were increasing in a dose‐dependent manner under TBT stress. In short, TBT‐induced biochemical and molecular responses in different tissues were reflected in the measured parameters in the test. On the basis of TBT residue levels in the natural environment, more long‐term experiments at lower concentrations will be necessary in the future.     

Absorption of bioactive human growth hormone after oral administration in the common carp (Cyprinus carpio) and its enhancement by deoxycholate

Summary Recombinant human growth hormone was administered orally to carp and serum levels of absorbed bioactive hormone were investigated using a highly sensitive Nb2 rat lymphoma cell bioassay and radioimmumoassay. Serum levels of bioactive hGH reached maximum values 30 min after oral intubation and then gradually decreased. Co-administration of the hormone with deoxycholate to fasted carp resulted in up to a 1000-fold increase in absorption compared to aqueous solutions of the hormone, but had no effect on the kinetics of the absorption process. Absorption of the hormone in starved fish was significantly greater than in fed fish. A linear dose-response relationship was observed for hGH in starved fish and the level of absorption in fed fish was influenced by the time interval from the last meal. The ratio of bioactive to immunoactive hGH in fasted fish indicated little loss of bioactivity and also that deoxycholate may be protective against hGH degradation. The present study demonstrates for the first time that biologically active hGH is absorbed in the common carp after oral intubation. Furthermore, the use of a biological detergent dramatically increased the extent of hGH absorption. Additional studies are required to establish the approapriate conditions (diet composition, feeding level, and frequency, etc.) in which polypeptide hormones could be introduced orally to fish.Abbreviations hGH human growth hormone - HRP horseradish peroxidase - RIA radioimmunoassay     

改良红鲫Dmc1基因编码阅读框的克隆及表达

Dmc1基因是一个在减数分裂前期Ⅰ表达的基因,其表达产物为减数分裂时同源染色体配对所必需。本实验根据普通红鲫Dmc1基因编码阅读框(ORF)序列设计引物,克隆了改良红鲫Dmc1基因(命名为IRCC-Dmc1)的ORF序列并将之插入到cDNA5-FRT/TO载体中,构建了改良红鲫Dmc1基因表达载体FRT/TO-IRCC-Dmc1-Myc。以FRT/TO-IRCC-Dmc1-Myc质粒转染HEK293T细胞,蛋白印迹杂交实验检测到改良红鲫Dmc1基因在HEK293T细胞中有着正确的表达。本文为将来进一步研究改良红鲫Dmc1基因的功能打下了基础。     

An in vitro study of long-term potentiation in the carp (Cyprinus carpio L.) olfactory bulb

Long-term potentiation (LTP) of synaptic transmission is considered a cellular mechanism for neural plasticity and memory formation. Previously, we showed that in the carp olfactory bulb, LTP occurs at the dendrodendritic mitral-to-granule cell synapse following tetanic electrical stimulation applied to the olfactory tract, and suggested that it is involved in the process of olfactory memory formation. As a first step towards understanding mechanisms underlying plasticity at this synapse, we examined the effects of various drugs (glutamate and GABA receptor agonists and antagonists, noradrenaline, and drugs affecting cAMP signaling) on dendrodendritic mitral-to-granule cell synaptic transmission in an in vitro preparation. Two forms of LTP are involved: a postsynaptic form (tetanus-evoked LTP) and a presynaptic form. The postsynaptic form is evoked at the granule cell dendrite following tetanic olfactory tract stimulation and is suppressed by the NMDA receptor antagonist, D-AP5, enhanced by noradrenaline, and occluded by the metabotropic glutamate receptor agonist, trans-ACPD. The presynaptic form occurs at the mitral cell dendrite following blockade of the GABA_A receptor by picrotoxin and bicuculline, or via activation of cAMP signaling by forskolin and 8-Br-cAMP.     

Diet spectrum of great cormorants (<Emphasis Type="Italic">Phalacrocorax carbo sinensis</Emphasis> L.) at the Donji Miholjac carp fishponds in eastern Croatia

This paper reports the results of a diet analysis from the digestive tracts of 203 great cormorants shot at the Donji Miholjac fishponds in eastern Croatia, in the period 2000–2002. Eight fish species were determined. The dominant species was common carp (Cyprinus carpio) with a relative frequency of 73.4%, followed by grass carp (Ctenopharingodon idella) (11.6%), bighead carp (Aristichthys nobilis) (7.2%), pikeperch (Sander lucioperca) (2.0%), wels catfish (Silurus glanis) (1.7%), pike (Esox lucius) (1.5%), topmouth gudgeon (Pseudorasbora parva) (1.5%) and Prussian carp (Carassius auratus gibelio) (1.1%). The diet spectrum of the great cormorants from the Donji Miholjac fishponds was in accordance with the structure of the fish population in the fishponds. The average stomach weight per bird was 244 g. When birds shot with an empty stomach were excluded, the average stomach weight increased to 286 g. The length of consumed fish ranged from 40–335 mm, with 47% of the fish belonging to the length category 100–149 mm. The study revealed no significant relationship between the weight of the consumed fish and the body weight of male and female cormorants.     

古生物在下古生界烃源岩有机质成熟度研究中的重要作用

对江苏下古生界动物化石有机碎屑（笔石、胞石和虫牙）反射率进行系统研究的结果表明,它们与镜质组反射率有着极为相似的光性特征和变化规律,即随埋深的增加而增高,因而它们均可和为有机质成熟度指标;并进而以牙形刺色变指标（ＣＡＩ）为纽带,分别建立它们与镜质组反射率之间的良好对应关系,提出它们的成熟度划分标准,为它们的实际应用奠定基础。     

应用SRAP标记分析福瑞鲤及其原始亲本的遗传结构

摘要：应用SRAP分子标记对建鲤（Cyprinus carpio var. jian）、黄河鲤（C.c.haematopterus）和福瑞鲤（FFRC Strain Common Carp,C.carpio）进行遗传结构分析。结果显示,筛选出的10个多态性较好的引物组合共扩增出110个位点,其中多态性位点92个,平均多...