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Four clonal lines of ayu, Plecoglossus altivelis Temminck & Schlegel, were produced through gynogenesis, mixed before hatching and reared communally. After 10 months, a randomly taken sample was subjected to a standardized shallow-water stressor. Haematocrit, haemoglobin, red blood cells count (RBC) and mean corpuscular volume (MCV) were obtained from stressed and non-stressed fish. DNA fingerprinting was used to confirm the clonal nature of the organisms and to identify the clonal line to which each fish belonged. We observed significant differences between clonal lines mostly in the haematocrit and MCV measured under no-stress conditions. Such differences are suggested to represent mainly genetic variance, on account of the common environment provided to all the experimental groups. The stress response ratio was lower than expected, mainly due to some unexpectedly high non-stress values. Heritability values (h2) were medium to high for the no-stress measurements (mean 0.238) and very low or zero for the stressed groups’traits (excepting one high value of 0.484). We conclude that the use of communally reared clonal lines represents a good tool for the characterization of the physiological traits, thus allowing for their utilization as genetic selection criteria. 相似文献
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Abstract. Based on a pooled sample of 367 specimens of juvenile Atlanlic salmon, Salmo salar L., from eight geographically distinct home rivers, stocks from Scotland and Newfoundland can be distinguished by meristic and morphometric character sets using discriminant analysis procedures. Reduced character sets require meristic counts of pectoral fin rays, dorsal fin rays, gill rakers and vertebrae, and morphometric measurements of standard length, pectoral and pelvic fin lengths, body depth and gape width. Regional differences based on these morphometric and meristic sets are substantiated by monomorphism at each MDH locus in Scottish fish in contrast to polymorphism at the MDH-1 and MDH-3 loci in Newfoundland fish. Only the morphometric discriminant function is highly accurate (>80%) in identifying home river origins of the fish examined with the discriminating power increasing with increased fish size. These findings for juvenile fish indicate that, while meristic, morphometric and electrophoretic criteria provide a likely means for distinguishing regional fish stocks, morphometric character sets would seem to offer the best possibility for identifying home river origins of adult Atlantic salmon in mixed fisheries. 相似文献
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Effect of triploidy on quality traits of shi drum (Umbrina cirrosa L.) until the second rearing year
Severino Segato Luca Fasolato Daniela Bertotto Angelo Libertini Stefania Balzan Adolfo Corato & Enrico Novelli 《Aquaculture Research》2007,38(1):59-65
Carcass and flesh morphometric, reological and chemical traits of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated through 7 months. Three age groups, 17‐, 21‐ and 24‐month‐old fish, were investigated. The effects of ploidy were statistically evaluated and the weight of fish was included in the model as a covariate because triploids grew less than diploids. As expected, fish weight was found to be significantly correlated with all the investigated morphometric traits, but showed a negative correlation with some chemical (pH) and colour traits (lightness) of raw fillet. In comparison with controls, triploid shi drums were characterized by different morphological traits that involved a slender body shape. In triploids, a reduction in condition factor, backbone weight, dressing index and an increase in the agility index were also recorded. When the commercial size (i.e. over 300 g) was achieved, triploids exhibited larger coelomatic and fillet (dorsal white muscle) fat deposition than diploids. Among reological traits, colour and texture were affected by ploidy; raw fillet lightness and cooked flesh tenderness were higher among triploids in all the investigated age groups. As fish were fed with a restricted feeding regimen, fillet fat deposition was supposed to be limited. Thus, the effects of ploidy on reological traits may be only partially explained by lipid fillet amount and are supposed to be more related to different fibre muscle architecture. 相似文献
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鲂属鱼类形态差异分析 总被引：4，自引：0，他引：4
为探讨鲂属鱼类种内及种间形态差异,采用单因素方差分析及主成分分析对厚颌鲂(Megalobrama pellegrini)、广东鲂(M.hoffmanni)、鲂(M.skolkovii)和团头鲂(M.amblycephala)共382尾样本的23个可数性状和24个可量性状进行分析和比较。结果表明,4种鲂的可数性状(尾部脊椎数),可量比例性状(口宽/头长、眼径/头长、腹鳍棘长/头长、肠长/体长、尾柄高/体长、第一鳔室长/体长、第二鳔室长/第一鳔室长、尾柄长/尾柄高)存在显著性差异,可作为4种鲂的判别性状。通过主成分分析法对可数性状(可量比例性状)构建了3个主成分,其贡献率分别为:26.28%(26.01%)、19.92%(12.05%)和8.04%(10.18%),累计贡献率54.24%(48.24%)。主成分散点图显示,4种鲂聚为4簇,广东鲂、团头鲂区分明显。 相似文献
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为比较企鹅珍珠贝[（Röding,1798）]海南金唇选育系（GLHH）、海南白唇选育系（WLHH）、广西金唇选育系（GLGG）和广西白唇选育系（WLGG）的生长存活差异,及了解4个选育系的生长规律,自2018年1月底至2018年12月底连续监测养殖于海南陵水黎族自治县新村港的4个企鹅珍珠贝选育系F3的存活率及其壳长、壳高、壳宽、铰合线长和体重的生长情况。使用单因素方差分析和生长模型拟合等方法对数据进行分析。结果显示,4个企鹅珍珠贝选育系的生长及存活率存在显著差异（<0.05）,海南金唇选育系的生长及存活率最优,广西白唇选育系的生长及存活率最差,表明企鹅珍珠贝的生长存活可能与环境、贝龄、壳色和地理种群有关。SGompertz生长模型为企鹅珍珠贝5个生长性状的通用生长模型。研究表明,4个企鹅珍珠贝选育系的生长规律存在差异,且企鹅珍珠贝5个生长性状的生长规律存在差异,其中壳长和铰合线长的生长拐点出现得最早,分别出现在7.9（GLHH）~8.5（WLHH）月龄和7.9（GLHH）~9.1（WLGG）月龄;其次是壳高和壳宽,生长拐点分别出现在11.6（GLHH）~15.9（WLGG）月龄和11.8（GLHH）~14.3（WLGG）月龄时;体重的生长拐点出现得最晚,在15.8（GLHH）~18.7（WLGG）月龄。该研究结果表明海南金唇选育系早期生长阶段具有高存活率和优良的生长性能,广西白唇选育系可能具有最大的生长潜力（生长性状的生长极限最大）,本研究可为企鹅珍珠贝的良种选育、健康养殖及优质珍珠的生产提供借鉴。 相似文献
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圆斑星鲽(Verasper variegatus)作为中国鲽形目(Pleuronectiformes)养殖鱼类的重要代表种类,具有生长速度快,可食用部分多,肉质细嫩等特点。为了探究圆斑星鲽形态性状与体重的关系,本研究分别测定11月龄、14月龄和17月龄3个不同生长期圆斑星鲽的体重及全长(FL)、体长(BL)、体高(BH)、头长(HL)、头高(HH)、尾柄长(CL)、尾柄高(CH)、吻长(SL)共计8个形态性状,分别进行相关分析和通径分析,剖析形态性状对于体重的直接作用和间接作用;利用回归分析的方法,建立各个时期以形态指标为自变量,体重为因变量的最优线性回归方程。结果显示,1)不同生长阶段,影响体重的重点形态指标存在差异,影响11月龄圆斑星鲽体重的主要形态性状为体高和体长,14月龄阶段为全长、体高和头长,17月龄阶段为全长和体高;2)11月龄、14月龄和17月龄形态性状对体重(Y)的多元回归方程分别为:Y=-186.412+17.381XBH+10.517XBL,Y=-362.484+13.145XFL+20.172XBH+21.199XHL,Y=-816.147+24.121XFL+40.575XBH;3)除本研究所包括的形态指标外,体厚可能为另外一个影响圆斑星鲽体重的重要指标。本研究阐明了体重与形态指标间的相关关系,为圆斑星鲽的良种选育提供了生物学依据。 相似文献
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SUMMARY: Five clonal lines of silver crucian carp Carassius langsdorfii were produced from natural maternal fish to estimate the variance and heritability of total length, bodyweight and gonadosomatic index (GSI). The larvae on the 10th day after hatching were reared together in a common rearing system with five duplicate systems. Another system was prepared using a separate system with two replications in each family. Estimation of variance and heritability were done in the first, third, fifth and 10th month for total length and bodyweight. Microsatellite DNA markers were used to identify the clonal lines in each communal rearing tank. Average heritabilities in the first month were 0.105 for total length (ranging from 0.21 to 0.03) and 0.127 for bodyweight (ranging from 0.22 to 0.06) then decreased in the third, fifth and 10th month. In contrast, intermediate levels of heritability from separate systems were observed. Likewise, relative heritability of GSI in the 10th month presented a high level in both rearing systems. Those heritabilities indicated that growth, total length, bodyweight and reproductive performances of silver crucian carp were affected by genetic influence. The results suggest that clonal lines of silver crucian carp are suitable as experimental animals for evaluations of environmental change and various pollutants through quantitative traits such as growth, reproductive and other physiological traits. 相似文献
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卵形鲳鲹不同月龄选育群体主要形态性状与体质量的相关性分析 总被引：5，自引：1，他引：4
为探讨卵形鲳鲹不同月龄选育群体主要形态性状对体质量的影响,跟踪测量了1月龄,4月龄,7月龄,10月龄和13月龄个体的全长(x1),体长(x2),体高(x3)和体质量(y),共测量2 635尾。运用相关分析、多元回归分析和通径分析的方法,计算了以体质量为因变量,其他形态性状为自变量的相关系数、通径系数和决定系数,剖分各性状对体质量的影响,建立最优多元回归方程。结果显示,在不同生长阶段,4个性状间的相关系数在0.017～0.960之间,除4月龄个体体高与其他性状间相关性不显著外,其他月龄群体各性状两两之间的相关性均达到了极显著水平;1月龄和4月龄个体全长对体质量的直接作用最大,7月龄、10月龄和13月龄个体则是体高对体质量的影响最大;各性状对体质量决定程度分析与通径分析变化趋势一致,各月龄群体全长、体长、体高估算体质量的多元线性回归方程的拟合度良好(86.9%～90.6%)。研究表明,影响体质量的主要形态因素已找出,选育时期不同,所选择的形态性状也应有所差异,为卵形鲳鲹选择育种提供了必要的技术参数。 相似文献
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Abstract – The morphology of three lake-resident Arctic charr, Salvelinus alpinus , populations was studied at two life-history stages in a common-garden experiment. The fish of the same year class were reared under standard hatchery conditions, and 27 morphometric variables (a truss network) were measured from the sampled individuals. Most of the total variation was explained by the overall body robustness, dimensions of the head and caudal peduncle length. After controlling for a body size, significant heterogeneity in body shape was found among populations at both ages. Independent of age, the populations were morphologically highly distinct, although some integration of characters could be found as the fish reached sexual maturity. Sexual divergence accounted for a large part of the within-population shape variation, the mature males having more robust bodies, larger head dimensions and longer pectoral fins compared with the mature females/immature fish. Although the cultured fish may not be totally representative of their wild counterparts, it is reasonable to expect that the observed morphological differences have a genetic basis, presumably reflecting adaptation to local environmental conditions experienced by the charr in their original habitat. 相似文献
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Fluctuating asymmetry is the random deviation from perfect bilateral symmetry owing to developmental perturbation, proposed as an indicator of sublethal environmental effects. This was measured in perch (Perca fluviatilis L.) from an acidic aluminium-rich lake. Eleven paired meristic and morphometric characters were scored for fluctuating asymmetry. Level of fluctuating asymmetry differed significantly between year classes for two of the meristic characters, lower extra gill rakers and upper extra gill rakers, and also for an index summarizing number of asymmetric meristic characters per individual. This year class variation in fluctuating asymmetry is probably due to large variation in water quality during early development of perch embryos in spring. For future work on fluctuating asymmetry on fish we recommend the use of as many year classes as possible in the analyses. 相似文献
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以1~6月龄三疣梭子蟹"中宁1号"为材料,采用Logistic、Gompertz和von Bertalanffy3种模型分别拟合了体质量、体长、全甲宽、甲宽、体高、大螯长节长、大螯不动指长及第一步足长节长共8个形态性状的生长特征,旨在寻找各性状的最佳生长模型,并对其增长规律进行研究。结果表明:三疣梭子蟹体质量性状生长过程以Logistic生长模型(R2=0.999)的拟合效果最佳;除体质量外的其它7个性状则均以von Bertalanffy生长模型(R2为0.990~0.994)拟合效果最好;各性状模型经ANOVA检验后均具有统计学意义(P0.01)。根据各性状的最佳生长模型得出各性状的极限值分别为体质量231.44 g、体长84.45 mm、全甲宽164.44 mm、甲宽128.47 mm、体高43.69 mm、大螯长节长59.96 mm、大螯不动指长90.89 mm、第一步足长节长37.20 mm。体质量的快速生长区间及拐点分别为2.14~3.91月龄及3.02月龄;其它7个性状快速生长区间的始速点为0月龄,终速点为2.05~2.35月龄,拐点在1月龄左右。各性状间的生长速率、生长加速率、相对增长率与绝对增长率存在一定差异。总之,体质量性状生长过程符合"慢-快-慢"的特征,其它性状则表现为"快-慢"的特征。以上结果可为三疣梭子蟹"中宁1号"选择育种及养殖生产提供参考依据。 相似文献
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为查明我国沿海不同地理群体龙头鱼（Harpadon nehereus）外部形态差异,采用传统形态学测定和几何框架度量法对8个龙头鱼群体共计199尾个体的29个可量性状进行了多元统计分析。主成分分析提取了排序前7位的主成分,获得累计贡献率达71.481%。主成分散点图显示舟山和潮州群体与其他群体差异较大,其中第1主成分反映了臀鳍大小及腹鳍至臀鳍间的躯体斜向大小差异;主成分2受到双眼间距离和口裂大小的影响。单因素方差分析显示仅特征值口裂/头长（MCL/HL）、腹鳍起点至脂鳍起点/体长（D3-D8/BL）、臀鳍起点至背鳍起点/体长（D5-D6/BL）和臀鳍基部末端至脂鳍基部末端/体长（D7-D10/BL）在各群体间未检测到显著性差异（P<0.05）。聚类树显示舟山群体聚在最外层,与其余群体差异较大,其次为海口和青岛群体。用逐步回归分析法选取9个作用最大的特征值建立判别公式,样本被判入青岛群体的判别准确率为100%,综合辨别率为66.9%。研究结果表明,不同群体龙头鱼在形态上存在一定差异,躯体长度、臀鳍位置和头部形态是区分它们的主要特征,但这些差异与地理分布没有形成对应关系。推测不同群体间频繁的交流使得形态差异受地理距离的影响较小,环境因子可能是导致特征差异的主要原因。 相似文献
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为研究罗氏沼虾(Macrobrachium rosenbergii)养殖群体表型性状间的相互关系及不同类群间的性状差异,本研究对人工养殖的罗氏沼虾雌、雄及“老头虾”3个类群共490个个体的体重、体长、全长等12个表型性状进行了相关分析、形态性状对体重影响的通径分析等。结果表明, 3个类群除上、下额刺数2个可数性状外,其他9个可量形态性状与体重都呈极显著的正相关(P<0.01);影响体重的关键形态性状在3个类群中各不相同,但体长、头胸甲长、第二步足长在3个类群中均是影响体重的关键指标;分别建立了各类群体重与关键形态性状的多元回归方程。聚类分析和主成分分析结果表明,雌、雄2个类群表型上更为相似,“老头虾”与雌性个体的差异最大。腹部轮廓特征(包括腹长、腹宽、腹高)、全长、体长及第二步足长对3个类群的差异贡献较大。雌性个体腹部发达,“老头虾”则第二步足尤为发达。本研究结果可为罗氏沼虾的选择育种、基础生物学及行业标准的制定提供数据资料。 相似文献
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盐度胁迫对遮目鱼幼鱼存活、生长及性状相关性的影响 总被引：1，自引：0，他引：1
设置盐度梯度为0、10、20、27(自然海水)、35,共5个实验组,每组3个平行。遮目鱼(Chanos chanos)幼鱼不经过过渡直接放入各梯度盐度中,养殖30 d后统计存活率,测量每尾鱼的体质量及各表型形态性状,以体质量为因变量(y),各形态性状为自变量(x)进行通径分析和决定系数分析。结果表明,盐度0组的幼鱼存活率最低(73.33%),增重率(573.94±231.58)%和特定生长率(6.23±1.16)%最高,与其他组差异极显著(P0.01)。除盐度0组外,其他各组幼鱼的存活率均在90%以上,且幼鱼特定生长率和增重率在各组之间差异不显著(P0.05)。相关分析表明,幼鱼的各形态性状与其体重之间呈极显著的相关关系(P0.01)。通径分析表明,遮目鱼幼鱼的体长、全长和体高对体重的影响最大,且在不同盐度胁迫下对幼鱼体重的决定作用不同,其他性状对体重的影响较小。建立了盐度胁迫下形态性状对体重影响的最优回归方程。 相似文献
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随机选取3月龄牙鲆Paralichthys olivaceus100尾,分别测量全长(X1)、体长(X2)、头长(X3)、体厚(X4)和体高(X5)共5个形态学指标和体质量(Y)。通过SAS软件进行相关性分析和回归分析,分别计算以形态性状为自变量对体质量的通径系数和决定系数,进而对各性状对体质量的影响进行剖分。明确影响3月龄牙鲆体质量的主要形态性状,为牙鲆选育提供数据支持和理想的测度指标。结果表明,各形态性状间及与体质量的相关系数均达到极显著(P0.01)。体长、体厚和体高对体质量的通径系数均达到极显著的水平(P0.01);所选形态性状对体质量的决定系数R2=0.945,表明所选形态性状是影响3月龄牙鲆体质量的主要性状。通过对各形态性状偏回归系数的显著性检验,剔除不显著的性状自变量后,建立最优的多元回归方程:Y=-4.988+0.763X2+2.997X+1.089X,各偏回归系数均达到极显著水平(P0.01)。 相似文献
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Severino Segato Daniela Bertotto Luca Fasolato Antonia Francescon Alvise Barbaro & Adolfo Corato 《Aquaculture Research》2006,37(1):71-77
Productive performances of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated over an experimental period of 76 days. Fish, selected according to body weight (196 specimens from each ploidy), were reared in tanks (two for each thesis) under the same environmental and dietary conditions. A practical extruded diet (crude protein: 43.4%; ether extract: 19.3%) was offered to fish according to a feeding rate that varied from 1% to 1.5% of live weight. Both at the beginning and at the end of the trials, samples of fish were submitted to morphometrics and chemical analysis. The final body weight and the specific growth rate of triploid fish were significantly lower than those of fish diploid. The feed efficiency of triploids showed a reduction in crude protein retention. Juvenile triploids evidenced a larger amount of coelomatic fat, and their gonads were atrophic. The whole‐body proximate composition of 3n fish was characterized by a higher ether extract and a lower crude protein content than 2n fish. Triploids had higher liver lipid content; there were no significant differences in viscera proximate composition. Sum, the results showed that chromosome set manipulation in this species can reduce productive performances at a juvenile stage, influencing some morphometric traits. 相似文献
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日本沼虾五群体形态性状对体质量的通径分析 总被引：4，自引：0，他引：4
为筛选出影响日本沼虾体质量的主要形态性状,以便确定人工选育的理想测定指标,以太湖、鄱阳湖、白洋淀、微山湖及淀山湖的野生日本沼虾为研究对象,随机选取各群体90尾虾测定19个形态指标,采用简单相关分析和通径分析等多元回归分析方法分析各群体对体质量作用较为突出的形态性状,并进行聚类分析。通径分析结果显示,太湖群体体长、头胸甲宽、第二步足长、头胸甲高、尾扇长对体质量的通径系数达到极显著,逐步回归建立其对体质量的回归方程、回归截距及相应的回归系数分别为–9.878、0.075、0.314、0.011、0.320、0.222;鄱阳湖群体头胸甲长、尾扇长、尾节宽、头胸甲宽、头胸甲高、尾节高、体长性状对体质量的通径系数达到极显著,回归截距和相应的回归系数分别为–1.618、0.392、–0.280、0.703、0.524、–0.359、0.688、–0.061;白洋淀群体体长、头胸甲宽、第二步足长和尾扇长对体质量的通径系数达到极显著,其回归截距和相应的回归系数分别为–4.796、0.082、0.222、0.007、0.136;微山湖群体头胸甲长、腹节高、第二步足长、腹节宽对体质量的通径系数达到极显著,其回归截距和相应的回归系数分别为–7.644、0.248、0.329、0.025、0.301;淀山湖群体体长、第二步足长、头胸甲宽、尾节宽、腹节宽对体质量的通径系数达到极显著,其回归截距和相应的回归系数为–6.257、0.019、0.018、0.164、0.264、0.162。体长与头胸甲性状在不同群体中都对体质量的作用十分明显。聚类结果显示,地理位置越接近,形态上越相似。研究表明,各个地区被保留的性状与体质量的复相关系数为0.965、0.904、0.902、0.971、0.955,为影响各自群体体质量的主要自变量。 相似文献