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1.
Correlation, multiple regression, and path analyses were used to investigate the relationships between body weight and three other morphological traits in juvenile Japanese sea cucumbers Apostichopus japonicus . We measured live body weight (BW), body length (BL), numbers of papillae (NP), and numbers of tube feet (NF) at 60, 80, 100, and 130 days post-hatching (dph). We calculated path correlation coefficients, correlation indices ( R 2 ), and coefficients of determination with BW as the dependent variable and the other morphological traits as independent variables. The coefficient of variation for BW was high across all age groups, and all measured morphological traits were significantly correlated ( P < 0.01). BL had the greatest direct eff ect on BW across all age groups (60 dph, 0.526;80 dph, 0.404;100 dph, 0.620;and 130 dph, 0.681), while NF had the greatest indirect eff ect on BW across all age groups (60 dph, 0.528;80 dph, 0.452;100 dph, 0.666;and 130 dph, 0.603). Regression analyses between morphological traits and BW indicated that R 2 was greater than 0.85 only in the 100-dph specimens. The indirect eff ects of the other measured morphological traits on BW were age-dependent. The optimal regression equations, as determined with stepwise regression, were, for 60-dph specimens: BW 60 =10 (-3.04+0.092BL+0.014NP+0.014NF)( R 2 =0.632);for 80-dph specimens: BW 80 =10 (- 3.035+0.056BL+0.017NP+0.02NF)( R 2 =0.686);for 100-dph specimens: BW 100 =10 (- 3.742+0.069BL+0. 633 · lg (NP)+0. 464 · lg (NF))( R 2 =0.893);and for 130-dph specimens: BW 130 =10 (- 2.472+0.065BL+0.012NP)( R 2 =0.774). Our work clarified the correlation between various morphological traits and body weight of a commercially-important sea cucumber species ( A . japonicus ). Our predictive models for body weight might be useful for the aquaculture and selective breeding of A . japonicus . These models might also provide theoretical support for the indirect selection of traits that are difficult to select directly.  相似文献   

2.
Estradiol treatment during early life stages of tiger puffer Takifugu rubripes induces feminization in genetic males.However,the ovaries in genetic males may revert to testes once estradiol treatment is halted.Therefore studies should investigate molecular mechanisms underlying ovary-to-testis recovery in genetic males after treatment.In the present study,tiger puffer were exposed to 10,and 100μg/L 17β-estradiol(E 2)from 15 to 100 days post-hatching(dph),then gonad phenotypes and expression profi les of six sex-related genes(cyp19a,foxl2,dmrt1,amh,sox9a,and sox9b)were characterized after the exposure.Results showed that both 10 and 100μg/L E2 induced ovarian development in genetic males at 100 dph.However,all ovaries induced by 10μg/L E2 first developed into intersexual gonads and subsequently reverted to testes after the exposure.As for treatment of 100μg/L E2,while the rest of the ovaries maintained morphological stability,percentages of intersexual gonads reached 38%-57%,and none were reverted to testes.Increased mRNA levels of cyp19a,foxl2 and sox9b and decreased mRNA levels of dmrt1,amh,and sox9a were observed during the ovarian development in genetic males.While contrary gene expression profiles were detected during ovary-to-testis transformation.The mRNA levels of all the six genes were increased during the development of intersexual gonads.These results indicated that up-regulation of dmrt1,amh and sox9a is associated with initial ovary-to-intersexual transformation,and suppression of foxl2,cyp19a and sox9b is essential for complete ovary-to-testis recovery in genetic males.This research will help to trace the molecular processes underlying gonadal transformation in teleosts.  相似文献   

3.
在人工培育条件下,采用实验生态学方法,对绿鳍马面鲀(Thamnaconus modestus)仔、稚、幼鱼生长、发育与摄食特性的变化进行了研究.结果表明,绿鳍马面鲀仔、稚、幼鱼的各生长指标可拟合为具有1~2个生长转折点的2~3段直线,其中全长、体长、体质量、肛前长、头长、吻长和体高可拟合为3段直线,眼径可拟合为2段直线...  相似文献   

4.
The objectives of this present research were to assess the heritability of growth traits under low temperature conditions in turbot(Scophthalmus maximus L.), and to analyze the correlation between body weight(BW) and body length(BL). There were 536 individuals from 25 full- and half-sib families involved in this study. During the entire 90-day period, which was initiated at 233 dph(day old) and ended at 323 dph, the individuals' BW and BL were weighed consecutively six times every 18 days. The heritability of BW and BL and the correlation between these two traits were estimated based on an individual animal model with the derivative-free restricted maximum likelihood(DFREML) method. These results showed that the specific growth rates(SGR) of 25 families was from 0.75±0.11 to 1.05±0.14 under water temperature of 10.5–12°C. In addition, the heritability of BW and BL estimated under low-temperature were 0.32±0.04 and 0.47±0.06, respectively. The BW had a medium heritability(0.2–0.4), and the BL had a high heritability(0.45), which suggested that selection for increased weight and length was feasible. Moreover, there was potential for mass selection on growth. The genetic and phenotypic correlations between BW and BL were 0.95±0.01 and 0.91±0.01(P 0.01), respectively. A significant correlation between BW and BL showed that BL could be instead of BW for indirect selection, which could be effectively implemented in the breeding program.  相似文献   

5.
The aim of this study was to evaluate the genetic parameters of the growth performance of Takifugu rubripes. Heritabilities and genetic correlations were estimated for body weight (BW), body length (BL), total length (TL), chest measurement (CM) and trunk length (TKL) of T. rubripes from measurements of progeny at 6 months and 12 months. The results showed that the heritability was 0.37 for BW6, 0.19 for BL6, 0.35 for TL6, 0.29 for CM6, 0.26 for TKL6, 0.36 for BW12, 0.26 for BL12, 0.25 for TL12, 0.31 for CM12 and 0.15 for TKL12. The range of genetic correlations estimated at 6 months was 0.025–0.725 and ?0.002–0.706 at 12 months. The results indicated that genetic improvement for faster growth rate or increased body weight in cultured T. rubripes was effective. Based on selection theory, the selection strategy for traits with medium heritability is flexible. Considering that these growth traits do not reach the high level of heritability, family selection should be expected. Given positive genetic correlations among BW, BL, TL, CM, and TKL at 6 months, the five traits could be improved simultaneously through selective breeding. As there was high genetic correlation only between BW12, BL12 and TL12, and negative correlations between TKL12 and BL12 as well as between CM12 and TL12, and only BW, BL and TL at 12 months could be improved simultaneously.  相似文献   

6.
日本对虾仔虾呼吸和排泄的初步研究   总被引:3,自引:0,他引:3  
本文采用水瓶法和径流装置研究了不同温度下摄食和饥饿的日本对虾(Penaeus japonicus)仔虾(P)的呼吸与排泄。结果表明,日本对虾仔虾体长与干体重呈指数函数关系,DW=0.006e^0.515L(r^2=0.999,n=16);耗氧和氨排泄率随着温度的升高而提高、随着仔虾体重的增长反而变小;耗氧和氨排泄率与体重呈幂函数关系,30和26℃下耗氧率(R)与体重的关系方程式分别是R=2.669DW^-1.041(r^2=0.953,n=8)和R=2.370DW^-0.708,(r^2=0.533,n=8),30和26℃下氨排泄率(E)与体重的关系方程式分别是E=36.81DW^-0.615(r^2=0.654,n=8) 和E=15.28DW^-0.795(r^2=0.652,n=8);饱食仔虾的耗氧率明显高于饥饿的仔虾,因摄食使仔虾(P15)额外消耗的能量为4%-20%,仔虾的特殊动力作用(SDA)大约在摄食5-7h后发生,并可持续作用10h左右。  相似文献   

7.
湄洲湾位于福建沿海中部,作者于2008年1月(冬季)、10月(秋季),依据《海洋监测规范》(GB17378-2007),在湄洲湾东吴港区附近设置3条潮间带断面,进行大型底栖动物调查采样.调查结果表明:共采获潮间带大型底栖动物283种,其中多毛类94种、软体动物91种、甲壳动物74种、棘皮动物9种、鱼类5种、其它类群动物10种.C断面种类最多179种.调查期间大型底栖动物平均生物量20.07g/m^2,平均栖息密度645.9ind/m^2,B断面生物量最高,A断面栖息密度最大.年平均去灰干重3.61g(AFDW)/m^2,依据Brey(1990)的公式计算,潮间带大型底栖动物次级生产力5.33g(AFDW)/(m^2·a),年平均P/B值为1.93.调查海域潮间带大型底栖动物种类数量、生物量、次级生产力、P/B值均高于海坛海峡潮间带.  相似文献   

8.
利用静水密闭式呼吸仪,测定了不同温度(10、12、……、30℃)条件下褐菖鼬(Sebastiscus marmoratus)幼鱼耗氧率和排氨率变化.结果表明,温度对幼鱼耗氧率和排氨率均有显著影响(P〈0.05).温度10~30℃,幼鱼耗氧率、排氨率变化范围分别为0.02~0.30mg/(g·h)和2.64~10.01ug/(g·h),温度26、16℃时耗氧率和排氨率分别上升至峰值,分别为最小值10℃组的15.00、3.79倍;温度(F)对幼鱼耗氧率R0[mg/(g·h)]和排氨率RN[ug/(g·h)]的影响可分别用多项式表示:R0=-2.00×10^-5 T4+1.50×10^-3 T3-3.69×10^-2 T2+0.3978T-1.5376,R2=0.988和RN=3.00×10^-5 T6 -4.00×10^-3 T5+0.1996 T4-5.1111T3+70.817T2-501.10T+1415.80,R2=0.964;幼鱼的氨熵变化范围为0.02~0.19,其蛋白质供能比变化范围为5.64%~56.65%,平均蛋白质供能比为22.56%;各温度跨度代谢率Q10值均值为4.02,18~28℃代谢率Q10值为2.81±0.09与鱼类平均Q10值较接近;各温度跨度组排泄率Q10均值为0.93,对比同一温度跨度组代谢率和排泄率Q10值,代谢率Q10值均大于排泄率Q10值两倍以上,最大组间相差达7倍.因此,幼鱼能量消耗的供能物质以脂肪和碳水化合物为主,蛋白质为辅.此外,温度变化对幼鱼代谢的影响程度明显大于对排泄的影响,且其适宜生长温度为18~28℃.  相似文献   

9.
应用X射线衍射(XRD)方法对南海北部西侧海域315个表层沉积物<2μm的粘土组分进行分析.结果表明,本研究区粘土矿物有伊利石、绿泥石、蒙脱石和高岭石,其组合特征在不同区域表现出明显的差异.根据粘土矿物的空间分布特征以及研究区的海底地形特征,研究区大致可以分为3个不同区块:A区是珠江口外的大陆架区域;B区是海南岛以东陆架陆坡区域;C区为西沙海槽至西沙群岛附近区域.根据研究区表层粘土矿物分布特征、周围河流供给的主要粘土成分以及洋流搬运作用,发现A区高岭石(平均含量为19%)主要来自珠江,伊利石与绿泥石(平均含量分别为53%和18%)主要由台湾的河流提供,有珠江物质的混合,蒙脱石含量较低(平均含量为10%).B区的高岭石(平均含量为13%)主要由海南岛的河流提供,蒙脱石(平均含量为16%)主要由吕宋岛的河流提供,B区东部的伊利石和绿泥石来自台湾的河流,B区西部伊利石和绿泥石主要来自红河、越南中部河流,海南岛物源亦有贡献.C区高岭石含量较低(平均含量为12%),越南中部河流和红河为C区蒙脱石(平均含量为14%)的主要物源区,C区东部伊利石和绿泥石来自台湾的河流,C区西部伊利石和绿泥石主要来自红河、越南中部河流.  相似文献   

10.
测记耳石生长轮纹数量,依据耳石日轮对采自珠江口的棘头梅童鱼(Collichthys lucidus)的日龄进行了鉴定、并据此研究了其产卵期和生长特性.棘头梅童鱼的产卵期为12月至次年的7月,主要集中在2、4、5月,产卵高峰出现在5月,占样本总数的27.27%;其次为2月,占18.18%.用直线、幂函数和指数函数关系对棘头梅童鱼的生长特性进行回归分析,体长范围为29.8~104.0 mm的棘头梅童鱼的体长与体重关系为幂函数关系,体重生长为匀速生长;体长随日龄的生长关系以幂函数模型符合程度较好,体重与日龄的生长关系则符合指数关系和幂函数关系.研究结果表明,利用耳石日龄来推算棘头梅童鱼的产卵期是可行的,并可用于研究一定体长范围内鱼的生长.  相似文献   

11.
利用PCR-SSCP技术对379尾凡纳滨对虾组织蛋白酶Cathepsin L(CTSL)基因多态性进行检测,采用最小二乘法对多态性与生长性状的相关性进行分析;利用Real-time quantitative PCR检测CTSL基因mRNA的差异表达情况。结果表明:引物C6 (F/R)扩增片段具有多态性,其扩增产物具有CC、CT和TT 3种基因型,TT基因型与CC基因型相比在第6外显子92 bp处发生了C→T的突变,为沉默突变。最小二乘法分析结果表明,在体重、体长、第一腹节长和尾节长这4个指标上CC和CT基因型显著高于突变型TT(p<0.05),而在头胸甲长和头胸甲宽2个指标上,CC基因型显著高于CT和TT基因型(p<0.05)。CTSL基因mRNA在凡纳滨对虾各组织、不同性别个体肌肉组织、极端体重个体肌肉组织中相对表达量大小顺序分别为:肝胰脏>胃>眼柄>心脏>消化腺;雌虾>雄虾;极大个体>极小个体。结论:CTSL基因多态性对凡纳滨对虾生长性状有显著影响,可以作为影响该虾生长性状的候选基因,为该虾的选育提供分子遗传标记;CTSL基因mRNA的分布情况表明此基因可能正向调控对虾生长。  相似文献   

12.
In a controlled laboratory experiment, fish in two treatment groups were exposed to B(a)P or B(a)P+PCB77 repeatedly over 1 year. Fish were held in a flow-through system and sampled on day 0, week 3, and on months 3, 6, 9, and 12. Each sampling (except week 3) was followed by exposure in water under static conditions. Exposure was terminated by restoring the flow-through within a maximum period of 24 h. Hepatic CYP1A remained significantly induced in juveniles even 3 months after the first exposure. The induction response in liver was more persistent in comparison to the gill response in juveniles. Sex influenced CYP1A expression in both organs of control fish and in both exposure groups. Suppression of CYP1A occurred in females even under repeated exposure. Liver GST activity showed sex differences, control females having higher activities than control males on the same sampling day. GST activity showed increases and decreases under both exposures possibly indicating the overriding influence of some other factors. Increased levels of fluorescent aromatic compounds (FACs) were detected in bile only in females exposed to B(a)P and PCB77 for 9 months. Liver UDPGT activity, length, weight, and condition showed no differences related to exposure or gender. The study was supported by Norwegian Research Council and the Ministry of Oil and Energy in Norway.  相似文献   

13.
吴翠琴 《台湾海峡》2009,28(1):60-64
采用半静态暴露的方式研究己烯雌酚(DES)和辛基酚(OP)对真鲷幼鱼血浆性激素含量的影响.将真鲷幼鱼暴露于一定浓度的DES和OP时间为6周,用放射免疫法测定对照组和染毒组血浆中的17β-雌二醇(E2)和睾酮(T)浓度.结果表明,DES和OP严重干扰了真鲷幼鱼的内分泌系统,特别是对17β-雌二醇含量的影响非常显著.  相似文献   

14.
南海北部陆坡区是中国最具潜力的天然气水合物聚集区。通过对研究区似海底反射层(BSR)、水深及热流值分布进行交会,得到了水深、热流双因素对天然气水合物形成的共同控制机理。研究认为,热流值中等(70~83mW/m^2)的地区最有利于天然气水合物的形成和聚集,热流值升高,天然气水合物形成的水深有总体增大的趋势。另外,天然气水合物的形成也需要良好的盖层条件。模拟了当上覆泥质沉积物盖层厚度不同时,天然气水合物形成所需的最低水深,并对不同泥质沉积物盖层厚度对天然气水合物稳定带底界面和厚度的影响做了研究和探讨。当泥质沉积物盖层的厚度越大时,天然气水合物形成的水深可以更浅;当泥质沉积物盖层厚度较小时,天然气水合物的形成则需要更大的水深。另外,当水深越大时,天然气水合物稳定带的底界面(BGHSZ)越深,天然气水合物稳定带的厚度越大。  相似文献   

15.
研究了地衣芽孢杆菌(Bacillus licheniformis)对尖吻鲈(Lates calcarifer)的生长及消化酶活性的影响.地衣芽孢杆菌制剂(含量为10×108cfu/g)分别以0.0%(对照组)、0.1%、0.2%、0.3%、0.4%、0.5%和0.6%的比例添加到饲料中,投喂初始体重为17.47±0.19 g的尖吻鲈,养殖时间8周.随着地衣芽孢杆菌添加量的增加,尖吻鲈的增重率和特定生长率逐渐增高,在0.5%组达到最大,增重率提高9.77%,特定生长率提高4.56%;同时该组的肥满度也显著高于对照组(p〈0.05).尖吻鲈的增重率、特定生长率、饲料系数、存活率、脏体比和肝体比在各组间都没有显著差异(p〉0.05).尖吻鲈的前肠蛋白酶在0.2%组达到最大,并显著高于对照组(p〈0.05),其他组别及部位的消化酶则低于对照组或差异不显著.结果表明,地衣芽孢杆菌对尖吻鲈的生长有一定促进作用,但此作用与消化酶变化相关不明显.  相似文献   

16.
采用以BSA为基础的微卫星标记技术对红鳍东方鲀(Takifugu rubripes)雌、雄群体进行性别差异标记筛选的研究。用雌、雄各30个个体构建雌、雄基因池,利用66对微卫星引物扫描雌、雄基因池。在雌、雄基因池中扩增出差异条带的引物有8对。用两个各包括30个雌、雄个体的群体对这8对引物进行两轮个体验证。结果表明,引物f383在两个雌、雄群体中扩增出的差异条带与性别都呈极显著相关性(r分别为0.710和0.673)(P0.01),f383是与红鳍东方鲀雄性呈正相关的微卫星标记。红鳍东方鲀性别差异微卫星标记的获得,为其性别相关基因的克隆和性别决定机制的研究提供理论基础。  相似文献   

17.
测定了相手蟹属(Sesarma)红螯相手蟹(S.haematocheir)和褶痕相手蟹(S.plicata)线粒体16SrRNA基因部分片段的序列,二者的序列长度相同,均为533bp,且A、T、G、C的含量相似,分别为198bp(37.1%),206bp(38.6%),84bp(15.8%),45bp(8.4%)和200bp(37.5%),205bp(38.5%),81bp(15.2%),47bp(8.8%);二者的序列有49处差异,其中21个位点为转换、22个位点为颠换和6个缺失/插入位点。进一步对20种相手蟹属蟹类的长度为361bp的16SrRNA基因同源序列进行分析,发现AT的含量为78.6%~82.9%,明显高于GC的含量,且存有91个变异位点。从NJ树和遗传距离来看,在分布于中国的3种相手蟹中,无齿相手型(S.dehaani)和红螯相手蟹的亲缘关系最近(d=0.0151),而它们与褶痕相手蟹的亲缘关系则较远(d=0.0924/0.09231。分布于中国的相手蟹和分布于北美的相手蟹之间存在着较大的遗传距离(差异),表明它们之间有着较远的亲缘关系,互为单系起源。  相似文献   

18.
肌肉生长抑制素抑制动物肌肉的生长发育.根据本实验室克隆的大黄鱼(Pseudosciaena cro-cea)肌肉生长抑制素(MSTN)基因编码序列设计引物,用RT-PCR扩增目的片段,构建MSTN-pET-28 a重组表达质粒,将其转化到大肠杆菌BL21上并用1.0 mmol/dm3IPTG诱导表达,SDS-PAGE电泳检测该目的蛋白大小约为44 kDa,与理论值大小符合.用0.25 mol/dm3KCl染色后从凝胶中切取该蛋白且回收.该回收蛋白与弗氏佐剂等量混合后注射ICR小鼠制备多克隆抗体,并用Westernblot检测该抗体.免疫印迹结果在44 kDa的位置上出现棕色条带,表明大黄鱼肌肉生长抑制素的多克隆抗体制备成功.这为今后对肌肉生长抑制素功能的研究奠定了基础.  相似文献   

19.
通过室内实验模拟了脊尾白虾(Exopalaemon carinicauda)对苯并[a]芘(benzo[a]pyrene,Ba P)的生物富集,通过非线性曲线拟合获得脊尾白虾对Ba P的富集动力学参数(吸收速率常数k1、释放速率常数k2、生物富集因子BCF、平衡状态下脊尾白虾体内Ba P含量CAmax、生物学半衰期B1/2).各动力学参数分别为:k1范围为12.34~24.96,平均值为18.80,k2范围为0.06~0.10,平均值为0.08,BCF范围为208.41~248.03,平均值为228.02、CAmax范围为12.40~93.79 ng/g,平均值为46.78 ng/g,B1/2范围为6.89~11.71 d,平均为8.95 d.脊尾白虾对Ba P的吸收速率常数k1、释放速率常数k2、BCF均随外部水体中Ba P浓度的增大而减少,CAmax、B1/2随外部水体中Ba P浓度的增大而增大.  相似文献   

20.
凡纳滨对虾CTSL基因与生长相关的SNP位点的特征   总被引:1,自引:0,他引:1  
对3个凡纳滨对虾品系的CTSL基因进行单核苷酸多态性(single nucleotide polymorphism,SNP)筛查,发现在生长指标差异的对虾中存在特征较为显著的7个SNP位点,其中3个属于外显子上的突变,4个属于内含子上的突变.B210对虾品系体重月平均生长量约为7.58g,体长月平均生长量约为2.31cm,B310对虾品系体重月平均生长量约为3.96g,体长月平均生长量约为1.48cm,HNIT对虾品系体重月平均生长量约为3.04g,体长月平均生长量约为2.18em.从市场价值来看,B210和B310品系比HNTr品系生长相对好些.进一步的PCR产物直接测序比较分析表明在生长指标较好的对虾品系,这7个SNP位点表现为纯合子;而在生长指标较差的对虾品系,在这7个SNP位点上31.6%表现为杂合子.虽然国内外有不少关于CTSL基因SNP位点的报道,但是与生长快慢的相关分析还鲜有报道,且这些SNP位点与前人发现的位点有所不同.本研究发现的CTSL基因的SNP位点与对虾生长快慢相关,将为凡纳滨对虾生长研究提供有用信息,从而有助于为对虾选育提供可靠的分子标记.  相似文献   

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