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1.
硬头鳟幼鱼部分形态性状和体重的关系   总被引:6,自引:0,他引:6       下载免费PDF全文
随机选取116尾硬头鳟(Oncorhynchus mykiss)幼鱼,测量其体长、体高、体厚、头长、眼径和眼间距、体重7个性状,计算各性状间的相关系数,采用通径分析方法计算以表型形态性状为自变量对体重作因变量的通径系数、决定系数及复相关指数,对各性状的影响大小进行剖析,明确影响硬头鳟幼鱼体重的主要外部形态性状,为硬头鳟...  相似文献   

2.
大菱鲆幼鱼表型形态性状与体重之间的关系   总被引:22,自引:0,他引:22  
随机选取1120尾3月龄大菱鲆幼鱼,测量其体长、全长、体高、头长、吻尖至鳃裂前缘长、尾柄长、尾柄高、体厚、体重等9个性状,计算各性状间的相关系数,采用通径分析方法计算以表型形态性状为自变量对体重作依变量的通径系数、决定系数及复相关指数, 对各性状的影响大小进行剖分,明确影响大菱鲆三月龄幼鱼体重的主要外部形态性状,为大菱鲆选育提供理论依据和理想的测度指标.结果表明:所测各表型性状与体重之间的相关系数均达到极其显著水平(P<0.01=;全长对体重的直接影响(R=0.702)最大, 对体重的决定程度(R2=51.84%)最高,是影响体重的主要因素;体高、体厚对体重的直接作用 (0.211 ,0.094)相对较小,主要通过体长的间接作用(0.5558,0.4342)影响体重.所选表型性状对体重的回归系数R2=0.911,表明所选性状是影响体重的主要性状.利用逐步回归分析方法建立以体长、体高、体厚为自变量估计体重的多元回归回归方程为:y=-6.216 1.294x1 0.518x2 1.293x3[动物学报 54(3):540-545,2008].  相似文献   

3.
通径分析在脊尾白虾育种形态性状选择中的应用   总被引:1,自引:0,他引:1  
选择胶州湾134只野生脊尾白虾(Exopalaemon carinicauda),对其体长、全长、头胸甲长及体重等24项性状进行测量,采用相关分析和通径分析的方法,分析了形态性状对体重的影响效果,并构建形态性状与体重的多元回归方程.结果表明,各形态性状与体重的相关系数均达到了极显著水平(P<0.01);全长、头胸甲宽、头胸甲高、第一腹长、第二腹高、第三腹宽对体重的通径系数达到显著水平(P<0.05);所选形态性状与体重的复相关指数R2=0.954;多元回归分析建立了全长、头胸甲宽、头胸甲高、第一腹长、第二腹高、第三腹宽对体重的回归方程Y=-2.783+0.014X1+0.130X4+0.095X13+0.126X5+0.045X6+0.149X11.试验结果为脊尾白虾良种选育研究提供了理想的测度指标.  相似文献   

4.
凡纳滨对虾各月龄性状的主成分与判别分析   总被引:8,自引:0,他引:8  
何铜  刘小林  杨长明  黄皓  相建海 《生态学报》2009,29(4):2134-2142
为了研究凡纳滨对虾各性状增长规律和判定最佳生长季节凡纳滨对虾的体格与月龄的关系,选择1~6月龄凡纳滨对虾各1000只,选择全长、体长、第一腹节背高、第三腹节背高、第一腹节背宽、头胸甲长和体重共7个性状,进行主成分与判别分析.结果表明:各月龄凡纳滨对虾性状之间均呈现显著的正相关(P<0.01), 其中以全长与体长的相关性最为明显,1月龄凡纳滨对虾体重与形态性状的相关系数较小.各月龄凡纳滨对虾的主成分有所不同,1~2月龄凡纳滨对虾的第一主成分为长度因子,第二主成分为宽度因子,第三主成分为高度因子;3月龄凡纳滨对虾的第一主成分与1~2月龄凡纳滨对虾一致,但第二主成分为高度因子,第三主成分为体重因子;4~6月龄凡纳滨对虾的第一主成分为体重因子,第二主成分为高度因子,第三主成分为宽度因子.1~3月龄凡纳滨对虾形态性状的增长优先于体重, 4~6月龄凡纳滨对虾体重优先于形态性状的增长.错过最佳生长季节的凡纳滨对虾的与体格大小相符的月龄可通过建立的判别式来判断,总的判别准确率为98.98%,其中2~4月龄凡纳滨对虾的判别准确率为100%.  相似文献   

5.
选择中华草龟、中华花龟及其杂种F1代幼龟共270只,测定了体重、背甲长、背甲宽、壳高、腹甲长等17个形态性状,采用相关分析、通径分析和多元回归分析研究了形态性状对体重的影响效果。结果表明,3种龟的测量形态性状与体重的相关系数均达到极显著水平(P0.01);通径分析显示背甲长、背甲宽、壳高、腹甲长和甲桥长对体重的通径系数达到显著水平,它们是直接影响体重的重要性状,其中背甲长和壳高是影响体重的共同性状;决定系数分析结果与通径分析结果有一致的变化趋势;所选形态性状与体重的复相关指数分别为R2=0.945、0.920和0.958,表明影响体重的主要自变量指标已经找到;利用逐步回归分析方法建立了以背甲长、壳高和腹甲长,背甲长、壳高和甲桥长,背甲长、背甲宽和壳高等3种龟的多元回归方程,分别为:Y=-156.764+9.895X1+17.449X3+14.347X4,Y=-295.040+13.443X1+40.603X3+38.632X9,Y=-280.960+14.908X1+14.290X2+43.129X3。  相似文献   

6.
为了研究瑶山亚种树鼩的体型特征,及体重与体尺性状间的关系,该研究对84只广西金秀大瑶山地区野生瑶山亚种树鼩的体重、体尺指标进行了测定和分析。数据测量结果显示雌、雄个体间,体重、胸宽差异显著(p0.05),体高差异极显著(p0.01)。在体重与体尺以及体尺指标之间的相关性研究中,除体重与躯干长,躯干长与体高、体斜长、胸宽、胸深无显著性相关关系(p0.05)外,体长与胸宽、尾长与躯干长呈显著的相关关系(p0.05),其余各项体尺指标之间均存在极显著的相关关系(p0.01)。以体重为因变量,体高、体长、尾长、体斜长、胸宽、胸深、躯干长指标作为自变量作逐步回归分析,回归方程:体重=-138.63+5.73×体长+9.51×体斜长+22.78×胸宽。该研究确定了广西野生瑶山亚种树鼩的体尺正常范围,为中缅瑶山亚种树鼩的鉴定提供更完善的基础生物学数据。  相似文献   

7.
浙江沿海游泳虾类报告Ⅲ   总被引:12,自引:1,他引:12       下载免费PDF全文
继浙江沿海游泳虾类报告Ⅰ(1959.9)、Ⅱ(1980.2)之后,作者又整理了以往的及近几年所得的标本,共9种,隶属7科8属,国内尚未有详细的报道,现将这些种类主要形态特征作简要描述,并附外形图,以供参考。一、对虾科 Penaeidae 1.印度对虾(Penaeus indicus)(图1见封2,下同) 体长120毫米。额角超过第一触角柄,上缘具7齿,后3齿在头胸甲上,下缘具4齿,额角基部不隆起成三角形,中部微下曲;额角侧沟较浅,不达头胸甲中部,仅达胃上刺下方;具触  相似文献   

8.
不同月龄哲罗鲑主要形态性状与体重的关系   总被引:1,自引:0,他引:1  
杨贵强 《动物学杂志》2016,51(5):876-886
为确定影响哲罗鲑(Hucho taimen)体重的主要形态性状,随机选取5个生长阶段共计710尾哲罗鲑为实验对象(3月龄240尾、6月龄180尾、12月龄110尾、18月龄90尾、36月龄90尾),测量其体重(y)、体长(x_1)、体宽(x_2)、体高(x_3)、头长(x_4)、眼径(x_5)、尾鳍长(x_6)、尾鳍高(x_7)、尾柄高(x_8)9个性状。通过相关分析、通径分析和回归分析,计算相关系数、通径系数和决定系数,获得相关回归方程,对不同月龄间的形态性状对体重的影响程度进行了比较分析。结果表明,3月龄、6月龄、18月龄和36月龄个体体长对体重的直接作用较大,12月龄个体则是体宽对体重的影响较大。利用逐步回归分析方法,以体重为依变量(y),形态性状为自变量(x_1~x_8),建立了哲罗鲑不同月龄最优多元线性回归方程分别为:y3=﹣14.911+1.561 x_1+3.448 x_2+5.232 x_3;y6=﹣70.321+5.192 x_1+0.962 x_2+0.473 x_3;y12=﹣217.446+7.129 x_1+23.147 x_2+44.055 x_3;y18=﹣891.041+20.234 x_1+65.786x_2+53.266 x_3;y36=﹣5748.099+88.187 x_1+301.984 x_2+66.702 x_7。该研究结果为哲罗鲑选择育种的具体应用提供了重要参考依据。  相似文献   

9.
采用相关性和通径分析研究不同规格黄鳍鲷 (Sparus latus) 的体质量与9个形态性状之间的关系, 确定各形态性状中影响不同规格黄鳍鲷体质量的主要外部形态指标。结果显示, 三种不同规格黄鳍鲷的主要形态性状(x1—x7)与体质量均呈极显著正相关 (P<0.01) , 而吻角、吻高与体质量未达到显著正相关(P>0.05)。三种不同规格黄鳍鲷主要性状间的相关性达到极显著水平 (P<0.01) 。与小规格黄鳍鲷体质量相关程度较大的形态性状依次为体高、全长、体长、尾长、吻长、头长等, 与中规格黄鳍鲷体质量相关程度较大的形态性状依次为全长、体长、尾长、体高、头长、眼距和吻长, 相关程度最低的是吻角和吻高, 与大规格黄鳍鲷体质量相关程度较大的形态性状依次为体长、全长、头长、体高和眼距。通径分析表明, 体高对小规格黄鳍鲷体质量的直接作用达到极显著水平, 直接决定作用系数为0.878。全长、体高对中等规格黄鳍鲷体质量的直接作用达到极显著水平, 从直接作用系数来看, 以上两个性状的直接和间接决定系数总和为0.880。体长、体高对大规格黄鳍鲷体质量的直接作用达到极显著水平, 这两个形态性状的直接和间接决定系数总和为0.969。研究表明, 在逐步多元回归方程中, 体长、全长和体高是影响黄鳍鲷体质量的主要形态参数。  相似文献   

10.
为了解人工养殖的克氏原螯虾(Procambarus clarkii)亲虾的生长和形态性状,为人工放养亲本的选择提供参考依据,测定了342尾体重大于20 g的克氏原螯虾的体重(W)、全长(TL)、头胸甲长(CL)、头胸甲宽(CW)、螯足长(ChL)和螯足宽(ChW),比较了雌性和雄性生长和形态参数的差异性,模拟了各参数间的回归方程,并探讨了各参数间的相关性。结果显示,雌性个体体重、螯足长和螯足宽的均值显著低于雄性,而头胸甲长和头胸甲宽的均值则显著高于雄性,全长和丰满度在雌雄之间差异不显著。雌性和雄性个体的优势全长范围均为90~119. 99 mm,优势体重范围分别为20. 0~39. 9 g和30. 0~44. 9 g。克氏原螯虾全长-体重的关系为W_♀=0. 000 01×TL~(3. 381 3)、W_♂=0. 000 01×TL~(3. 230 9),雌性和雄性均为正异速生长;头胸甲长-体重的关系为W_♀=0. 000 1×CL~(3. 215 5)、W_♂=0. 000 2×CL~(3. 179 8);头胸甲长-全长的关系为TL_♀=2. 928 6+2. 027×CL、TL_♂=-5. 036 9+2. 370 1×CL;头胸甲宽-头胸甲长的关系为CL_♀=5. 479 2+1. 942 3×CW、CL_♂=9. 646 8+1. 765 6×CW;螯足宽-螯足长的关系为ChL_♀=-13. 721+6. 679×ChW、ChL_♂=-4. 828+6. 148 7×CW。相关性分析表明,总体上6个参数之间均有显著的正相关关系,其中与体重相关性较高的为全长和头胸甲长与宽。  相似文献   

11.
The shell length, height, and width, live body weight, and edible tissue weight of Manila clam of 1, 2, and 3 years of age were measured, and their correlation coefficients were calculated. The shell morphological traits were used as independent variables, and live body weight or edible tissue weigh used as a dependent variable for calculating the path coefficients, correlation index and determination coefficients. The results showed that the correlation coefficients between each shell morphological trait and the live body weight or edible tissue weight were all highly significant (P < 0. 01). The shell height at 1-year old clams was highly correlated with the live body weight and edible tissue weight. The shell width of 2- to 3-year-old clams was strongly associated with the live body weight, while the shell length was closely linked to the edible tissue weight. The results of coefficients of determination for the morphological traits against weight traits agreed well with the results of path analysis. The correlation indices for all morphological traits against weight traits were approximately the same as determination coefficients regardless of clam age. The correlation indices (R2) of morphological traits against the live body weight of clams of all ages and edible tissue weight of 1-year-old clams were larger than 0.85, but R2 of morphological traits against the edible tissue weight of 2- and 3-year-old clams was smaller than 0.85, indicating that some other factors might be associated with the edible tissue weight of 2- and 3-year-old clams. Multiple regression equations were obtained to estimate shell length X1 (cm), shell height X2 (cm), shell width X3 (cm) against live body weight Y (g), edible tissue weight Z (g): for 1-year-old clams: Y = ?4.317 + 0.18X1 + 0.147X2, (X1 < 0.01, X2 < 0.01), Z = ?1.011 + 0.095X2, (X2 < 0.01); for 2-year-old clams: Y = ?15.119 + 0.249X1 + 0.176X2 + 0.688X3, (X1 < 0.01, X3 < 0.01), Z = ?4.248 + 0.198X1, (X1 < 0.05, X3 < 0.01); and for 3-year-old clams: Y = ?25.013 + 0.415X1 + 1.184X3, (X1 < 0.01, X3 < 0.01), Z = ?7.082 + 0.119X1 + 0.332X3, (X1 < 0.05, X3 < 0.01).  相似文献   

12.
13.
长春花主要农艺性状与文多灵含量的相关及通径分析   总被引:3,自引:0,他引:3  
文多灵(vindoline)具有重要的药用价值。本文利用反相高效液相色谱法检测了23种国内外长春花主栽品种的文多灵含量, 对文多灵含量与品种的12个主要农艺性状(包括株高、节间距、茎直径、一级侧枝数、叶片长、叶片宽、叶片长宽比、百片叶重、全株叶片重、花瓣直径、种荚长度和种子数/荚)的相关性和通径进行了分析。相关性分析表明, 文多灵含量与一级侧枝数、茎直径、节间距、叶片宽、株高、全株叶片重、百片叶重、花瓣直径和叶片长呈正相关, 其中与一级侧枝数和茎直径的相关性达到显著水平(P<0.05), 与节间距的相关性接近显著水平; 与叶片长宽比、种荚长度和种子数/荚呈负相关。通径分析结果表明, 长春花的主要农艺性状中, 节间距、一级侧枝数和全株叶片重对文多灵含量的正影响达到了显著水平(P<0.05),通径系数分别为0.959、0.716和.431, 说明节间距、一级侧枝数和全株叶片重可以作为高含量文多灵长春花品种选育的重要参考指标。  相似文献   

14.
The aim of this study is to characterize the population biology (sex ratio, size structure, relative growth of reproductive characters and realised fecundity) of the crab Microphrys bicornutusfrom Isla Margarita, Venezuela. Nearly 100 crabs were collected and fixed monthly during 1998. In the laboratory, crabs were sexed and measured: maximum carapace length, chelae length, chelae and abdomen width for females and first pleopod length for males. Additionally, 96 ovigerous females were collected to determine fecundity. The following measurements were taken for each female: body wet weight (BWW), body dry weight (BDW), egg wet weight (EWW), egg dry weight (EDW) and number of eggs (NE). The following determinations were made: relative fecundity (RF) = NE/BDW and reproductive output (RO) = (EDW/ BDW) × 100. Relative size at the onset of maturity (RSOM) was calculated as minimum ovigerous female/female's maximum size. The results indicate that the sex ratio is nearly 1:1 during the entire year. Ovigerous females and moulted males and females were observed throughout the year. Size frequency distribution and size at the onset of sexual maturity, estimated by relative growth of the sexual secondary characters and RSOM value, differed from those estimated in studies done in Jamaica and Buchuaco, Venezuela.  相似文献   

15.
A new strain of Manila clam with orange shell color was produced after selection within a full-sib family for two generations. In the present study, the shell length, height, and width, and the live body weight of the orange strain were measured, and their correlation coefficients were calculated. The shell morphological traits were used as independent variables, and the live body weight was used as the dependent variable for calculating the path coefficients, correlation index, and determination coefficients. The results showed that the correlation coefficients between each shell morphological trait and the live body weight were all highly significant (P < 0.01). The correlation indices (R2) of morphological traits against the live body weight of clams were larger than 0.85, indicating that the morphology traits were the main factors affecting the body weight. Multiple regression equations were obtained to estimate shell length X1 (cm), shell height X2 (cm), and shell width X3 (cm) against live body weight Y (g): Y = ? 2.62 + 0.34 X1 + 0.145 X2, (X1 < 0.05, X2 < 0.05). The results suggest that the shell length could be used as the main trait for selective breeding and could indirectly make a large improvement in the weight trait.  相似文献   

16.
A new chimaerid species closely related to Hydrolagus pallidus is described from 13 specimens captured on the Portuguese continental slope (north‐east Atlantic) by commercial longliners at depths of c . 1600 m. The new species is large‐bodied with a rose to light brown body colouration. Hydrolagus lusitanicus n.sp. presents a combination of external morphological characters that allow it to be clearly differentiated from its congeners, in particular, the ratios of pectoral fin length: pectoral fin width and pelvic fin length: pelvic fin width; in having a serrated posterior edge of the dorsal spine; a high number of ridges in the dental plates. Additionally in males, there are differences on the shape and number of hooks in the frontal tenacula, on the number of spines in the prepelvic tenacula and on the length of the pectoral fin margin.  相似文献   

17.
The relative growth of a number of morphological dimensions of the South American freshwater crab Trichodactylus borellianus (Trichodactylidae) were compared and related to sexual dimorphism. Crabs were collected from ponds in the Middle Paraná River in Argentina. A regression model with segmented relationship was used to test for relative growth between these measurements where breakpoints infer the body size at which crabs reach sexual maturity. In both sexes the carapace width and the length, height, and thickness of the right and left chelae were measured, as well as the male pleopod length and the female abdomen width. All of these measurements were found to show positive allometry with the exception of the male pleopod length and the left chelae, which did not show a breakpoint. In females the breakpoint for the abdomen width inferred a morphological sexual maturity at carapace width 6.9 mm. In males the break point for the pleopod length was at carapace width 6.6 mm, with that for the chelae measurements was between carapace widths 6.4 and 6.9 mm. The relative growth pattern in Trichodactylus borellianus was found to be similar to that recorded for other species of the family Trichodactylidae.  相似文献   

18.
The size distribution, length–weight relationship and size at the onset of sexual maturity of the orange mud crab (Scylla olivacea) from four geographically distinct locations (Taiping, Setiu, Kota Marudu and Lundu) representing Malaysian waters were analysed and estimated. Scylla olivacea was found in the size range of 47–134?mm carapace width. Males were significantly smaller in size but heavier than females. Geographical variation in carapace width and body weight were significant, but no interaction was found between sexes and locations. As shown by the length–weight relationships of S. olivacea, the males exhibited positive growth allometry whereas the females exhibited negative growth allometry. Males mature physiologically prior to attaining morphometric sexual maturity. Females, however, achieve physiological and morphometric sexual maturity in synchrony. No significant variation was found in the estimates of size at the onset of sexual maturity of males and females among different locations. We recommend the use of the third right walking leg merus length and carapace width to estimate the size at the onset of sexual maturity (morphometric maturity) for S. olivacea. Data obtained in this study serve as important baseline data for future mud crab resource management in Malaysia and were used to recommend minimum landing sizes for S. olivacea in each respective location based on the largest size at the onset of sexual maturity estimates were suggested.  相似文献   

19.
The invasion of Cherax quadricarinatus, the Australian redclaw crayfish, in the Sanyati Basin of Lake Kariba, Zimbabwe, is reported. A total of 79 crayfish were caught at 10 out of 12 sampling sites in the Sanyati Basin in November–December 2012. The average catch per unit effort (CPUE) varied from 1.1 to 4 crayfish per trap per night, carapace length ranged from 29 to 93.5 mm, and weight ranged from 4 to 196.2 g. Most crayfish were between 50 and 59.9 mm carapace length. Males (average 82.6 g) were significantly heavier than females (37.2 g) and males were larger in carapace length, carapace width, chela length and chela width. A feral population of C. quadricarinatus is now established in the Sanyati Basin. Possible modes of dispersal within the basin are discussed.  相似文献   

20.
Abstract

From January 1975 to June 1976, samples of Heterozius rotundifrons A. Milne Edwards, 1867 were taken monthly from the intertidal zone at First Bay, Kaikoura Peninsula (42°25′S, 173°42′E). Small crabs (< 8 mm carapace width) were never common; they were either too cryptic to be collected in quantity, or have a different habitat from larger crabs. Ovigerous females were present in all months except February (in both 1975 and 1976), but generally formed less than 50% of the total sample of females each month. The number of newly deposited eggs (0.75×0.81 mm) carried by females increased with increase in carapace width according to the equation y = -1123.56+102.97x (r 2 = 0.8213). Egg development lasted 3–5 months, and egg mortality during this period was almost 10%. The overall sex ratio for the 18-month sampling period was 1846 ♀ : 993 ♂, which suggests that females were approximately twice as numerous as males. However, when crabs were sorted into size classes it was evident that the sex ratio was not significantly different from 1:1 in crabs of 6–12 mm carapace width, whereas females significantly (P<0.001) outnumbered males in the 13–21 mm size range. The right and left chela were approximately equal in length in females of all sizes, but the right chela of large males was greatly enlarged compared with the left, and with the chelae of females of comparable carapace width. Increase in the growth rate of the males’ right chela commenced at a carapace width of approximately 11.0 mm. Since the smallest ovigerous female collected also had a carapace width of 11.0 mm, it is concluded that both males and females attain sexual maturity at this size.  相似文献   

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