Effect of Metal Ions on Protease Activities in the Intestines and Hepatopancreas of Red-white Ornamental Carp (Cyprinus carpio L)

[Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp（Cyprinus carpio L）.[Method] Effects of four kinds of metal ions （K＋,Na＋,Mg2＋ and Ca2＋） on protease activities in hepatopancreas,foregut,midgut,hindgut of red-white ornamental carp were studied by enzyme analysis method.[Result] Effects of four kinds of metal ions on protease activities of red-white ornamental carp were different in the range of experimental concentration from 25 mmol/L to 150 mmol/L.K＋ could promote protease activities in hepatopancreas and hindgut at different levels.Especially,K＋ had the promoting effect at low-concentration level,but the inhibitory effect at high-concentration level in midgut and the inhibitory effect in foregut.Na＋ had the promoting effect on protease activities in hepatopancreas,foregut and hindgut at different levels,but the inhibitory effect in midgut.Mg2＋ and Ca2＋ had the inhibitory effect on protease activities in intestinal and hepatopancreas at different levels.[Conclusion] This study provides basic data and theoretical foundation for researches on the digestive physiology of red-white ornamental carp or the development and optimization of compound feed.

恩诺沙星对湘云鲫(Triploid crucian carp)组织转氨酶(GPT、GOT)活性的影响

采用胸腔注射法,研究了恩诺沙星对湘云鲫(Triploid crucian carp)组织谷草转氨酶(GOT)和谷丙转氨酶(GPT)活性的影响。结果显示,给药后5 d,各试验组GPT、GOT酶活性均升高,与对照组之间呈显著差异水平(P<0.05);给药后10 d,各浓度组GPT酶活性有所降低,而GOT酶活性则继续升高,鳃的GOT酶活性达到了最大值;给药后15、20 d,各浓度组GPT酶活性继续下降,而肝脏、肾脏GOT酶活性在给药后15 d时达到最大值,之后开始下降;给药后25 d,鳃的GPT酶活性除200 mg/kg组外都恢复至正常水平,而肝脏、肾脏各浓度组的GPT酶活性显著低于对照组(P<0.05),肝脏的GOT酶活性恢复到了正常水平,而鳃和肾脏的GOT酶活性略高于对照组水平。

cGH Gene Transfer and PCR Detection in Crucian Carp

By inserting the CMV with HSV TK promoter into the plasmid pBlue-cGH which contained cGH gene, a chimeric expression vector was constructed for transgenic fish. After the vector was transferred into fertilized eggs of crucian carp by means of microinjection, the transgenic crucian carp was obtained. The result of PCR detection showed that the growth hormone gene of the exogenous carp was integrated into the genome of crucian carp, and the transgenic crucian carp displayed enhancement of its growth.

Screen for stage-specific expression genes between tail bud stage and heartbeat beginning stage in embryogenesis of gynogenetic silver crucian carp

A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169 TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS dot blot positive clones. Of the 79 known genes, 20 were enzymes or kinases involved in important metabolism of embryonic development. Moreover, specific expressions of partial genes were further confirmed by virtual northern blots. This study is the first step for making a large attempt to study temporal and spatial control of gene expression in the gynogenetic fish embryogenesis.

Comparative investigation on spindle behavior and MPF activity changes during oocyte maturation between gynogenetic and amphimictic crucian carp

The spindle behavior and MPF activity changes in the progression of oocyte maturation were investigated and compared with cytological observation and kinase assay between gynogenetic silver crucian carp and amphimictic colored crucian carp. MPF activity was measured by using histone H1 as phosphorylation substrate. There were two similar oscillatory MPF kinase activity changes during oocyte maturation in two kinds of fishes with different reproductive modes, but there existed some subtle difference between them. The subtle difference was that the first peak of MPF kinase activity was kept to a longerlasting time in the gynogenetic silver crucian carp than in the amphimictic colored crucian carp. It was suggested that the difference may be related to the spindle behavior changes, such as tripolar spindle formation and spindle rearrangement in the gynogenetic crucian carp.

Hydrodynamic Analysis of C-start in Crucian Carp

The kinematics of turning maneuvers of startled Crucian Carp (Carassius auratus) are presented. All escape responses observed are C-type fast-starts. The position of the center of mass and the moment of inertia of the fish are calculated. The results show that the position of the center of mass is always at 35% of the length of the fish from the head and the position of the center of mass and moment of inertia can be considered unchanged during C-start of Crucian Carp. Hydrodynamic analysis of the C-start is given based on the kinematics data from our experiments. The C-start consists of three stages. In stage 1, the tail fin of fish rapidly flaps in one direction, and a large moment acts on the fish′s body, which rotates around the center of mass with an angular acceleration. In stage 2, the tail fin flaps more slowly in the opposite direction at slower speed, the fish′s body rotates around the center of mass with angular deceleration and the center of mass of the fish moves along an arc. In stage 3, the moment approximately equals zero, the fish′s body stops rotating and the center of mass the moves along a straight line.

Effects of fishing handling stress on juvenile red crucian carp(Carassius auratus red variety)

The essay studies the influence of the different intensities of fishing stress on body weight （7.30 ± 1.48） g of red crucian carp juvenile body length, weight, fatness, feeding rate, specific growth rate, food conversion rate, intestinal protease, amylase and immunoglobulin. The result showed that body length, weight, fatness, feeding rate, specific growth rate of red crucian carp juvenile were significantly inhibited from fishing stress compared with the control group, and the magnitude of the inhibitory effect increased with the time going and increased. Fishing stress could increase the food conversion rate of red crucian carp juvenile, and the different intensity stress had no significant different influence. The intestinal protease activity decreased in the beginning, then increased, and was consistent with the level of the control group ultimately. High-stress group accelerated the decline of intestinal amylase activity of the juvenile. The stress increased the number of immunoglobulin of juvenile red crucian carp significantly, but the increase disappeard with the stress time extended.

miR-199-5p regulates spermiogenesis at the posttranscriptional level via targeting Tekt1 in allotriploid crucian carp

Background:Sperm abnormalities are one of the primary factors leading to male sterility,but their pathogenesis is still unclear.Although miRNAs are suggested to exert important roles in the regulation of spermatogenesis at both transcriptional and posttranscriptional levels,little is currently known regarding the regulation of sperm flagella assembly by microRNAs(miRNAs).The role of miRNAs in the development of sperm abnormalities in sterile triploid fish has not been studied.Results:In this study,we found that miR-199-5p was widely expressed in all detected tissues of different-ploidy crucian carp.As one of the testis-specific candidate markers,Tekt1 was predominantly expressed in the testis.Quantitative real-time PCR(qRT-PCR)analyses showed that the expression trend of miR-199-5p was exactly opposite to that of Tekt1.Through bioinformatics analysis,we identified a putative miR-199-5p binding site in the Tekt1 mRNA.We further identified Tekt1 as a target of miR-199-5p using luciferase reporter assay.Finally,we confirmed that miR-199-5p was necessary for sperm flagellar assembly and spermatogenesis in vivo via intraperitoneal injection of miR-199-5p antagomir or agomir in diploid red crucian carp.Moreover,miR-199-5p gainof-function could lead to spermatids apoptosis and abnormal spermatozoa structure,which is similar to that of allotriploid crucian carp.Conclusions:Our studies suggested that abnormally elevated miR-199-5p inhibited the sperm flagella formation in spermiogenesis by negatively regulating the expression of Tekt1,thereby causing sperm abnormalities of male allotriploid crucian carp.

Application Effects of Amino Acid Powder,Fermented Rapeseed Meal and Fermented Cottonseed Meal in Feeds for Allogynogenetic Crucian Carp

[Objective] To investigate the effects of amino acid powder, fermented rapeseed meal and fermented cottonseed meal on the growth performance, amino acid absorption, body composition and liver function of allogynogentic crucian carp. [ Method] The allogynogentic crucian carps with the average initial weight of 17.3 g were divided into control group and six experimental groups randomly. The allogynogentic crucian carps in the control group and experimental groups were fed a basal diet and the basal diets supplemented by amino acid powder, fermented rapeseed meal and fermented cottonseed meal, respectively. The growth rate and specific growth rate of allogynogentic crucian carps, the content of amino acids in serum and feeds, the composition indicators of body, muscle and liver, as well as the activities of glutamic-pyruvic transaminase （GPT） and glutamic-oxaloacetic transaminase （GOT） in liver and serum were determined, respectively. [ Result] The growth rate and specific growth rate （SGR） of allogynogentic crucian carps in the 3% amino acid powder group and the 6% fermented cottonseed meal group were increased greatly （ P 〈 0.05）, and no significant difference was found between experimental group and control group. The serum lysine content of the 3% amino acid powder group and the 6% fermented cottonseed meal group was higher than that of the control group. In the experimental groups, the absorption of four essential amino acids was up to a peak at 4 h after feeding, which was consistent with the control group. The body composition and liver function of allogynogentic crucian carps had no significant difference between the experimental groups and the control group. [ Conclusion] The 3% amino acid powder, 6% fermented cottonseed meal and 6% fermented rapeseed meal can substitute fish meal, cottonseed meal and rapeseed meal to improve the clrowth performance, amino acid absorption of the allogynogentic crucian carps.

Analysis of Phospholipids in Crucian Carp(Carassius auratus) Muscle by Offline HPLC-MALDI-TOF MS

The interest in the analysis of phospholipids(PLs), especially phosphatidylcholine(PC), has been increasing due to the importance of them in biochemistry as well as in industry. A method was reported based on the offline combination of MALDI-TOF MS and normal-phase HPLC for analyzing PLs extracted from crucian carp. Total PLs of crucian carp were extracted and then separated by HPLC before the collected subfractions were analyzed by MALDI-TOF MS. The mass spectra obtained show peaks of H+, Na+ and K+ adducts of PC molecules. It is shown that the prior separation of PLs by HPLC is highly necessary to remove the signal suppressing and to avoid the possible overlapping. With this method, 9 possible PC molecules in crucian carp and the corresponding fatty acid compositions were given from the well-resolved mass spectra.

Effect of lead on cytoskeletal protein stability in crucian carp Carassius auratus

Inorganic lead （Pb） is one of the most common environmental pollutants. Much evidence indicates that Pb exposure could directly affect fish growth and development. In this study, we investigated the cytotoxic effects of Pb on cytoskeletal protein stability at both protein and mRNA level in crucian carp Carassius auratus. Pb（NO3）2 treatment in concentration of 100 μmol/L resulted in decreased expression of both α- and β-tubulin but γ-tubulin as assayed with SDS-PAGE, Western Blot, and ELISA. In vivo and in vitro analyses on protein expression of tubulins are consistent. The effect of Pb on mRNA expression varied among different tissues. Our results suggest that cytotoxicity of Pb at protein translation level is stronger than at mRNA expression level.

Flash-boiled Clams with Crucian Carp

Marinate the clams in brine for 3 hours, until silt isdiffused, and keep them fresh. Draw the crucian carp,and make 3 or 4 diagonal cuts on the surface of bothsides.

转生长激素基因彩鲫(Colorful Curcaincarp)的获得及检测

The recombinant plasmid pFV2cfGH was constructed using Growth hormone gene which was cloned from the channel catfish cDNA library,the β-action promoter of carp and the polyadenylation signal from the salmon growth hormone gene, and recombinant plasmid pFV2cfGH was microinjected into the fertilized eggs of the colorful crucian carp. 60 transgenic Colorful Crucian carps total DNA were got ,and growth hormone gene were detected by PCR. The result shows that the channel catfish growth hormone gene had been transmitted into the genome of the Colorful Crucian carp and the integration rate is about 47%.

食醋对鲫鱼汤品质的影响

为探究食醋对鲫鱼汤品质的影响,以鲫鱼为原料,加食醋或不加食醋,将其熬制不同时间,对鲫鱼汤的色泽和营养物质进行分析。结果表明,食醋有利于鲫鱼中营养物质的溶出,如可溶性固形物;添加食醋后,随着熬制时间的增加,蛋白质含量先升高后降低,且可以使汤在短时间内获得丰富的矿物质;不加食醋,随着熬制时间的增加,鲫鱼汤的色差L*值明显升高,即汤色变白,且鲫鱼汤中脂肪、蛋白质、胆碱和Ca含量也明显增加;鲫鱼汤富含多种多不饱和脂肪酸,包括亚油酸、γ-亚麻酸、α-亚麻酸、花生四烯酸、二十碳五烯酸和二十二碳六烯酸,其占比达总脂肪酸的30%,且食醋对鲫鱼汤中的脂肪酸组成没有明显的影响。综上,食醋能加速鲫鱼营养物质的溶解,但熬制时间不宜过长,加食醋后熬制2 h时鲫鱼汤的营养最丰富。

一株鲫鱼致病性普通变形杆菌的鉴定及生物学特性研究

本研究对患病鲫鱼进行发病原因探究,致病菌特性分析,从而为鲫鱼病害的防控提供理论基础。通过从患病鲫鱼肝脏和肠道中分离纯化细菌,对分离菌进行16S rRNA序列分析、人工感染试验、生理生化鉴定、系统发育树构建,并通过纸片扩散法进行药敏试验,筛选敏感药物。从病鱼肝脏和肠道中均分离出菌株A,16S rRNA序列分析和理化特性均与普通变形杆菌Proteus vulgaris基本一致,人工感染试验证实菌株A为致病菌,LD50为9.77×10^(6)CFU/尾。菌株A对头孢唑啉、头孢拉定、氟苯尼考、卡那霉素、阿奇霉素及庆大霉素等6种抗生素高度敏感,对阿莫西林、红霉素、新霉素、克林霉素及多西环素等5种抗生素耐药。本次试验结果表明菌株A为普通变形杆菌,是此次鲫鱼病害的主要元凶,临床治疗可以根据药敏试验选用高度敏感抗生素进行治疗。

红鲫胚胎发育过程中Sox8基因对壬基酚胁迫的响应

【目的】明确红鲫SRY相关高迁移率族盒蛋白8基因(Sox8)表达模式及壬基酚(NP)暴露对红鲫胚胎发育过程中Sox8基因表达的影响,为揭示NP胁迫下红鲫胚胎发育畸形的分子机制提供科学依据。【方法】运用RACE克隆红鲫Sox8基因cDNA全长序列,通过ProtParam、ProtScale、InterPro、PredictProtein、DeepTMHMM等在线软件进行生物信息学分析,利用实时荧光定量PCR检测红鲫Sox8基因在各成体组织及不同胚胎发育阶段的表达情况,以及不同浓度NP暴露对红鲫胚胎期Sox8基因表达的影响。【结果】红鲫Sox8基因c DNA序列全长2163 bp,其开放阅读框(ORF)1176bp,共编码391个氨基酸残基;红鲫SOX8蛋白相对分子量为43798.30Da,理论等电点(pI)为6.90,脂溶指数为49.92,不稳定指数为66.04,总平均亲水性指数(GRAVY)为-1.026,其N端含有Sox_N二聚化结构域和HMG-box结构域;基于SOX8氨基酸序列相似性构建的系统发育进化树显示红鲫与鲫的亲缘关系最近。红鲫Sox8基因在各成体组织中广泛表达,以脑组织中的Sox8基因相对表达量最高,显著高于其他组织(P<0.05,下同);在红鲫胚胎发育过程中,Sox8基因的表达从受精后到14体节期呈逐渐下降趋势,但从21体节期开始Sox8基因相对表达量显著增高,直到孵化期始终维持在较高水平。在大多数情况下,NP暴露能显著影响红鲫胚胎发育过程中Sox8基因的表达,特别是14体节期后的发育阶段,NP暴露主要是不同程度地激活Sox8基因表达。【结论】Sox8基因表达在红鲫成体中具有组织特异性,且在胚胎发育过程中呈先降低后升高的变化趋势。NP暴露能显著影响红鲫胚胎发育过程中Sox8基因的表达,14体节期后Sox8基因表达水平升高可能是NP致畸红鲫胚胎的重要原因之一。

基于数值的鲫鱼游泳能力影响参数分析

鱼类游泳行为机理及游泳能力的影响因素是目前鱼类仿生学研究的热点问题。本文选取鲹科游动模式(carangiform)的典型—鲫鱼(crucian carp)作为研究对象,采用数值模拟的方法,利用动网格技术结合用户自定义函数(UDF),围绕运动参数、鱼体体型及游泳环境(壁面边界),以仿生鲫鱼到达动态稳定的巡游速度这一过程衡量鲫鱼游泳能力,对鲫鱼游泳能力的影响开展研究。结果表明:当摆动频率在0.07~5.50 Hz之间,摆幅系数在0.03~0.06之间,随着鱼体摆动频率和摆动幅度的增大,仿生鲫鱼获得动态稳定巡游速度的时间逐渐缩短,且巡航游速相应增加。将不同厚长比、体长的鲫鱼经过量化处理后进行数值计算,研究结果表明:以相同的摆幅和摆频向前游动,厚长比与游泳速度呈负相关,当厚长比小于0.166,仿生鲫鱼可获得更快的游泳速度;体长方面,将仿生鱼的体长设置为L,仿生稚鱼可更快速地到达巡游阶段,但到达动态稳定的巡航游速较低,约为0.6L s^(–1),仿生幼鱼在加速阶段速度较快,巡游阶段与仿生成鱼的动态稳定巡航游速基本一致,约为1L s^(–1);鱼体在壁面附近游动所产生的壁面效应会导致游泳速度降低,且双侧壁面对仿生鲫鱼游泳速度的影响较单侧壁面更为显著,当鱼体距单侧壁面0.5L,距双侧壁面0.8L时将不受壁面的影响。本文的研究结果可为鱼类仿生学研究提供有益参考。

基于机器视觉和改进YOLOv5s的鲫病害轻量级无损检测模型

以鲫(Carassius auratus)常见病害为例,从实际生产角度出发,提出了一种基于机器视觉和改进YOLOv5s的鲫病害轻量级无损检测模型,可实现鲫鱼体多种病害的同步无损快速检测。首先,通过利用Shuf-fleNetV2替换YOLOv5s主干网络,对模型进行轻量化改进;在此基础上,耦合一种基于卷积块的注意力机制[Convolutional block attention module(CBAM)]提高模型精准度;最后,结合空洞空间卷积池化金字塔[Atrous spatial pyramid pooling(ASPP)]提升模型鲁棒性。通过在自制鲫病害数据集上测试可知,文章所提出模型病害检测精确率可达92.0%,模型体积仅为14400 kb,优于当前相关主流模型(最高精确率为83.6%,最小体积为15750 kb),为水产养殖鱼类病害无损快速检测提供了技术支撑。

绿色发展背景下无骨鲫鱼的商业推广模式研究

本文通过对无骨鲫鱼深加工产品的数字化推广进行研究,旨在满足消费者需求的同时提高产品的附加值,从而带动区域经济的发展,提高农业生产者的收入水平,拓宽产品市场,提升黑龙江省农产品在国内外市场的竞争力。

饲料中添加发酵豆粕对湘云鲫生长性能、肠道及肝脏健康的影响

为研究饲料中添加发酵豆粕对湘云鲫幼鱼生长性能、肠道及肝脏健康的影响,试验以豆粕含量26%、鱼粉含量20%的饲料作为基础鱼粉组(FM组)饲料,在FM组饲料的基础上添加12%发酵豆粕等蛋白替代10%豆粕和2%鱼粉制成发酵豆粕替代组(FSM组)饲料,对初始体重为(37.26±0.16)g的湘云鲫幼鱼进行为期56 d的养殖试验。结果显示:与FM组相比,FSM组增重率、特定生长率、尾均摄食量、饵料系数、肥满度、脏体比、肝体比、干物质沉积率、蛋白质沉积率及脂肪沉积率均无显著变化(P>0.05);肌肉粗蛋白质含量显著提高(P<0.05),粗灰分含量显著降低(P<0.05),全鱼粗蛋白质、粗脂肪、粗灰分以及肌肉粗脂肪含量没有显著变化(P>0.05)。在肠道健康方面,FSM组肠道绒毛数目和绒毛高度和FM组间无显著差异(P>0.05);与FM组相比,FSM组血浆D-乳酸含量显著降低了21.5%(P<0.05),血浆内毒素含量和二胺氧化酶活性在FSM组和FM组间无显著差异(P>0.05);FSM组肠道脂肪酶活性较FM组显著提高了10.2%(P<0.05),胰蛋白酶、淀粉酶和Na+-K+ATP酶活性在两组间差异不显著(P>0.05);与FM组相比,FSM组肠道总超氧化物歧化酶活性和丙二醛含量无显著差异(P>0.05)。在肝脏健康方面,发酵豆粕添加对湘云鲫肝脏结构无明显影响,两组均肝细胞索明显,排列较整齐,肝细胞结构完整;与FM组相比,FSM组血浆谷丙转氨酶活性和总胆固醇含量显著降低(P<0.05),其中谷丙转氨酶活性显著降低11.3%,总胆固醇含量降低23.1%,溶菌酶活性和免疫球蛋白M含量显著提高(P<0.05),两组间甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇含量以及谷草转氨酶活性均无显著差异(P>0.05)。