黄颡鱼的两性异形和雌性繁殖特征

测定了黄颡鱼成体的体长、头长、头宽、头高、吻长、眼径、眼间距、眼后头长、体高、尾柄高、背鳍基前距、背鳍基长、尾柄长、腹鳍基前距、背鳍脂鳍间距、腹鳍臀鳍间距、尾鳍长、体重、去内脏体重等形态指标以及雌体的怀卵数量。雌性成体的体长显著小于雄性成体。其它局部特征皆与体长呈正相关,回归剩余值的t—检验表明,雌性成体的眼径、头高、体高、腹鳍基前距、体重显著大于雄性成体,其它局部形态特征不存在显著的两性差异。黄颡鱼雌体通过个体大小的增加和腹部形态的改变增加腹腔容量,增加繁殖输出。     

东海南部竹筴鱼形态特征参数及其相关性比较分析

2012年4月采集东海南部水域100尾竹筴鱼样本,测量其体长、全长、头长、头高、体高、体厚、吻长、眼径、眼后头长、尾柄长、尾柄高、体重等共12个形态特征指标.采用方差分析、偏相关分析、通径分析及回归分析,研究竹筴鱼东海南部种群各形态特征参数间的相关关系,确定与竹筴鱼体重显著相关的主要形态特征参数.结果表明:东海南部竹筴鱼的头长、头高、体厚、吻长、眼径、眼后头长、尾柄高、体重与体长呈指数相关(P＜0.01);而全长、体高、尾柄长则与体长呈线性相关(P＜0.01).竹筴鱼体长和体重的拟合方程为:y=0.0185x28736 (R2=0.9714);竹筴鱼的b值为2.8736,小于3,为负异速增长,即体长的增长速度要高于体重.头长、头高、体高、眼后头长、尾柄高对竹筴鱼体质量的影响存在显著关系;对竹筴鱼体质量的直接作用影响大小依次为:头长(0.242**)＞尾柄高(0.223**)＞头高(0.197**)＞眼后头长(0.161**)＞体高(0.155**),建立了竹筴鱼体质量的最优回归数学模型:y=-46.845 +3.892x1+9.623 x2+ 12.354x3+7.128x4+ 8.361x5.     

中华绒螯蟹微卫星标记与生长性状相关性的初步分析

研究采用30个微卫星标记分析同池养殖的长江水系中华绒螯蟹群体,以筛选生长性状(体重、体长和体宽)相关的分子标记。结果表明,位点ESIN33、ESC29和ESC57与体重、体宽和体高呈极显著相关(P<0.01);位点ESC65与体高、体宽呈极显著相关(P<0.01),与体重呈显著相关(P<0.05)。不同基因型间的多重比较表明,ESIN33位点的AC基因型、ESC29位点的DD基因型、ESC65位点的BB基因型的平均体重、体宽和体高均高于其他基因型,且差异显著,是生长性状的优势基因型。研究结果可为中华绒螯蟹的分子标记辅助选育提供参考。     

大菱鲆幼鱼表型形态性状与体重之间的关系

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].     

五指山猪GH、IGFBP3基因SNPs检测及与生长性状的关联分析

以五指山猪为试验材料,采用PCR-SSCP和测序相结合技术,对GH基因和IGFBP3基因进行多态性检测,并分析其与生长性状(体质量,体高,体长和胸围)的相关性。结果表明,GH基因第2外显子存在一处G→A转换,属沉默突变,该位点与生长性状关联分析显示,BB基因型的体重显著高于AA基因型和AB基因型;IGFBP3基因第2外显子存在一处G→C颠换,属沉默突变,该位点与生长性状关联分析显示,AA基因型的体高显著高于BB基因型;IGFBP3基因第4内含子存在一处碱基C缺失,该位点与生长性状关联分析显示,AA基因型体重显著高于AB基因型和BB基因型。研究将为五指山猪生长发育规律、系统选育及矮小机制等方面研究提供了遗传学依据。     

建鲤GHR基因多态性及与增重相关的SNP位点的筛选

生长激素是调控动物生长的关键因子,它通过与膜蛋白生长激素受体结合后发挥作用,因此生长激素受体基因的变异对动物生长有着重要的影响。实验根据已分离的4个建鲤jlGHRs基因,通过测定来自6尾建鲤的序列,共找到38个SNP位点。使用PCR-RFLP方法检测了353尾建鲤在其中5个SNP位点(1a内含子3 A43G、1a外显子8 A361G、1b外显子8 C12T、2a外显子8 A555G和2b外显子8 A315G)的基因型,分析了不同基因型与生长性状的相关性。结果表明5个位点均与增重显性相关;1a内含子3 A43G还与体高/体长和体厚/体长显性相关;1b外显子8 C12T与体高/体长和尾柄高/尾柄长显性相关;1a外显子8 A361G和2a外显子8 A555G也与尾柄高/尾柄长显性相关。数据分析还显示增重标记个数富集4个以上的个体明显比标记少的个体生长快,在选育群中增重标记数有2个的个体最多占30%,而增重标记数4个以上的只占14%,说明存在着较大的选育空间。实验筛选的5个位点可以作为建鲤分子育种的有效标记。       

中华鳖MyoD1基因SNP鉴定及其与生长性状的关联分析

为了研究生肌决定因子1(MyoD1)基因多态性与中华鳖生长性状的相关性,采用直接测序法在MyoD1基因上共检测到6个SNP位点(T-49G、A-38G、C91T、A187T、C880T和T1522A),其中C880T位于外显子上,属于错义突变。对从同批繁殖、同块稻田养殖的2冬龄中华鳖群体中随机选取的178只个体中各位点的基因型进行检测。结果显示,所有位点在中华鳖群体中的平均有效等位基因数、平均观测杂合度和平均期望杂合度分别为1.636 5、0.349 3和0.375 4,除A187T位点外,其余5个位点的基因型频率分布均符合Hardy-Weinberg定律。采用一般线性模型分析各位点与中华鳖生长性状之间的相关性,研究发现,T-49G位点GG基因型个体的背甲宽显著大于TT基因型,A-38G位点AG基因型个体的背甲宽显著大于AA基因型,A187T位点TT基因型个体的体高显著大于AA基因型,T1522A位点AA基因型个体的体质量显著大于TT、TA基因型,其余位点不同基因型个体间的生长性状均不存在显著差异。T-49G、A-38G、A187T和T1522A位点与生长性状显著相关,可作为中华鳖分子标记辅助育种的候选标记。     

尼罗罗非鱼ghrelin基因的多态性及其与生长性状相关SNP位点的筛选

为了研究尼罗罗非鱼(Oreochromis niloticus)生长激素促分泌素基因(ghrelin)的多态性及其与生长的相关性, 研究以两个尼罗罗非鱼群体(快长群体和基础群体)的DNA样本各40份为模板, 通过PCR扩增和测序获得ghrelin基因序列。通过Dnasp v5和MEGA 5.0分析序列多态性、筛选有效SNP 位点; 采用Snapshot法对两个群体子代ghrelin基因中SNP位点进行基因分型, 然后分析SNP位点基因型与生长性状的相关性。结果表明, 快长群体ghrelin基因中的单核苷酸变异位点数(S)比基础群体要少, 而核苷酸多态性(Pi)和平均核苷酸差异数(K)要略高于基础群体。共筛得3个有效SNP 位点(S1、S2和S3), 均分布于第1个内含子中。遗传结构分析表明, 3个SNP 位点在两个群体的子代中均为低度多态性位点(PIC0.25), 但处于Hardy-Weinberg平衡(P0.05);快长群体子代中3个SNP 位点的观测杂合度、期望杂合度和多态信息含量等遗传多样性参数均小于基础群体子代的相应值, 3个SNP 位点的遗传多样性参数、基因型和基因频率在同一群体中高度一致, SNP 位点之间完全连锁。两个群体子代中3个SNP 位点处的优势基因型相同, 但快长群体子代中优势基因型频率要明显大于基础群体子代中相应基因型频率。对两个群体子代的生长性状与SNP基因型进行关联性分析的结果表明,尼罗罗非鱼个体的多项生长指标(体重、体长、体高、头长和尾柄高等)在不同基因型中存在显著差异(S1:GG AG, S2:TT AT, S3:AA AT)(P0.05)。D1双倍型(S1:GG, S2:TT, S3:AA)所对应的尼罗罗非鱼个体的多项生长指标(体重、体长、体高、头长和尾柄高等)显著高于D2双倍型(S1:AG, S2:AT, S3:AT)。以上结果表明, 尼罗罗非鱼ghrelin基因3个SNP 位点完全连锁, D1双倍型与快长性状密切相关, 可作为尼罗罗非鱼分子标记辅助育种的候选标记。     

MC4R、POU1F1基因对京海黄鸡生长性能的遗传效应

以MC4R和POU1F1基因为候选基因, 采用PCR-SSCP和DNA测序技术检测两个候选基因在京海黄鸡群体中的单核苷酸多态性(SNPs), 同时对候选基因与京海黄鸡生长性能的相关性进行了研究。结果表明, MC4R基因编码区第662 bp位置有G→C碱基的点突变, 在京海黄鸡中检测到AA、AB、BB 3种基因型, A等位基因频率为0.929, B等位基因频率为0.071; 在POU1F1基因exon3在序列的第5 231 bp位置有一个A→T碱基的点突变, 检测到CC、CD、DD 3种基因型, C等位基因频率为0.500, D等位基因频率为0.500。采用GLM模型分析基因型对生长性能的遗传效应, 结果表明, MC4R基因AA基因型个体的4、8、12周龄体重显著地高于BB型个体(P<0.05), 16周龄体重差异极显著(P<0.01); POU1F1基因CD基因型个体体重极显著高于CC型和DD型(P<0.01)。因此推测MC4R和POU1F1基因可能是影响鸡生长性状的主效基因或与主效基因紧密连锁的标记基因, 能够在分子标记辅助选择中用于对鸡生长性状的遗传改良。     

转大麻哈鱼生长激素基因鲤表型性状与体质量的相关性及通径分析

随机选取二龄转大麻哈鱼生长激素基因鲤和对照鲤各30尾,运用相关分析和通径分析的方法研究全长、体长、体高、尾柄高、尾柄长、头长、吻长、眼径、眼间距、体厚10个表型性状对体质量的影响程度,以此确定影响二龄转基因鲤和对照鲤体质量的主要表型参数.相关分析结果表明:转基因鲤和对照鲤的大部分表型性状与体质量间的相关系数均达到极显著水平(P<0.01).通径分析结果显示:体长和体高可以作为预测转基因鲤体质量的主要表型参数,转基因鲤体长对体质量的通径系数为0.572,体高对体质量的通径系数为0.415,体长和体高直接决定体质量;而体厚和头长可以作为预测对照鲤体质量的主要表型参数,对照鲤体厚对体质量的通径系数为0.610,头长对体质量的通径系数为0.377,体厚和头长对体质量具有决定作用.     

Polymorphism of somatostatin gene and its association with growth traits in Chinese cattle

Somatostatins play a crucial role in the regulation of growth and development in vertebrates, especially muscle growth. We assessed the association of somatostatin gene polymorphisms with growth traits by PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) and DNA sequencing methods in 694 individuals from six Chinese cattle breeds. A novel single nucleotide polymorphism, G126A, was detected, and significant associations were found with body length, body height, hip width, heart girth, and hucklebone width index. Polymorphism of the somatostatin gene was found to be highly associated with growth traits in the Qinchuan breed at various ages. Gene frequency analysis showed significant differences among the breeds. Individuals with genotype AA had significantly lower body height, body length, hip width, and hucklebone width values compared to AG at 1.5 years old, and had significantly lower hip width, body length and hucklebone width compared to AG at 2 years old. At 2.5 years old, populations with genotype AA had significantly lower body length, hip width and hucklebone width than AG individuals, with the exception of the Luxi breed, in which two genotypes were found. The Luxi and Ximentaer crossbreed had the lowest frequency of the G allele, while the highest G allele frequencies were found in the Luxi breed.     

SNPs in the myostatin gene of the mollusk Chlamys farreri: Association with growth traits

Myostatin (MSTN) is a member of the transforming growth factor-β superfamily which negatively regulates growth of muscle tissue. In this study, 103 cultivated Chlamys farreri individuals were screened for polymorphisms in the MSTN gene using PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods. Two mutations were found: A/G at position 327 in exon 2, which caused an amino acid change from Thr to Ala (Thr305Ala), and C/T at position 289 in exon 3, which caused an amino acid change from Cys to Arg (Cys422Arg). One way ANOVA of the SNPs and growth traits showed that genotype GG of primer M5 had significantly higher body mass, soft-tissue mass, adductor muscle mass, shell length, shell height, absolute growth rate of shell height and body mass than those of genotype AG and AA (P < 0.05). Genotype frequencies of genotype AA, AG and GG were 68.94%, 27.18% and 3.88%, respectively. The results present evidence that the C. farreri MSTN gene may be selected as a candidate gene for these growth traits.     

IGFBP-3基因多态性及其与中国美利奴羊部分羊毛性状的关联性分析

采用PCR-SSCP方法对中国美利奴羊和哈萨克羊中IGFBP-3基因的多态性进行了检测, 并对不同基因型与中国美利奴羊部分羊毛性状间的关联性进行了分析。结果在位于内含子1区的一段178 bp的扩增产物经SSCP分析后出现了3种基因型, 基因型AA、AB和BB及等位基因A、B在中国美利奴羊中的频率分别为0.70、0.24、0.06和0.82、0.18; 在哈萨克羊中的频率分别为0.87、0.13、0.00和0.93、0.07。序列分析发现: 在该序列的122位碱基表现多态性 (g.122 G>T)。所研究的两个群体在该位点上均处于Hardy-Weinberg不平衡状态(P<0.01)。不同基因型对部分羊毛性状有一定的影响: 不同基因型个体在剪毛后体重和净毛率上没有明显差异。AA、AB及BB基因型个体的羊毛伸直长度逐渐变短, 其中AA与AB基因型之间差异极显著(P<0.01)。AA型个体的剪毛量和羊毛密度要明显低于AB型(P<0.01)和BB型个体(P<0.05); 羊毛纤维直径则明显高于AB型(P<0.01)和BB型(P<0.05)个体。     

Leptin基因的PCR-SSCP与牛体重、体尺指标的相关性

利用PCR—SSCP技术研究了南阳牛、秦川牛、郏县红牛、西镇牛、鲁西牛和荷斯坦奶牛6个牛品种539个个体leptin基因的遗传多态性。结果表明,PCR扩增产物大小为330bp,PCR—SSCP分析表现出多态。南阳牛、秦川牛、郏县红牛、西镇牛、鲁西牛和荷斯坦奶牛的A等位基因频率分别为0．558,0．492,0．571,0．658,0．591,0．615;B等位基因频率分别为0．442,0．508,0．429,0．342,0．409,0．385。不同基因型与体重、体尺等生长性状指标相关性分析的结果表明：南阳牛群体内除12月龄的体高和日增重、18月龄的坐骨端宽和日增重外,BB型个体的六月龄、十二月龄、十八月龄、二十四月龄体斜长、胸围、体重、坐骨端宽、体高和日增重均显著的大于AB和AA型个体（P〈0．05）;秦川牛群体内BB基因型个体十字部高上显著高于群体AA、AB型个体（P〈0．05）,即BB〉AA、AB,可作为秦川牛体尺指标（十字部高）候选基因之一,但在体重、胸围、体长指标上均无显著差异（P〉0．05）,所以不宜作为体重、胸围、体长指标候选基因;郏县红牛群体内AB与BB基因型个体在十字部高和坐骨端宽上显著高于群体AA型个体（P〈0．05）,而群体内不同基因型在体重和体尺指标（体高、体斜长、胸围）上无显著差异（P〉0．05）。序列分析表明,leptin基因多态是第66位发生G→T、第67位发生A→C及299位发生新的单核苷酸突变C→T所造成。     

郏县红牛DGAT2基因多态性与生长性状的相关性分析

利用PCR-RFLP技术对随机抽取的92头郏县红牛的DGAT2基因进行多态性分析。结果表明, DGAT2基因第6内含子的PCR扩增产物被限制性酶TaqⅠ酶切消化后表现多态性。经电泳检测后, 显出AA、AB两种不同基因型。该基因座处于Hardy-Weinberg平衡状态, 通过对郏县红牛DGAT2基因多态性与体重及体尺指标的方差分析显示：郏县红牛DGAT2基因不同基因型对郏县红牛体重和体长有显著影响(P<0.05), 而对其他体尺指标在统计学上无显著影响(P>0.05), 且初步认为AB基因型对选择有正向效应。     

Expression profiles and association analysis with growth traits of the MyoG and Myf5 genes in the Jinghai yellow chicken

In order to analyze the association of single nucleotide polymorphisms (SNPs) in the MyoG and Myf5 genes with chicken growth traits, PCR-SSCP approach was used to detect the (SNPs). The general linear model was used to analyze gene interaction and genetic effects between different genotypes and growth traits of the Jinghai yellow chicken. For the MyoG gene, three genotypes (AA, AB and BB) were detected in the Jinghai yellow chicken population. Gene sequencing revealed one mutation (T36C) in the genotype BB in comparison to the genotype AA. For the Myf5 gene, three genotypes (CC, CD and DD) were detected in the Jinghai yellow chicken population. Gene sequencing revealed one mutation (A1313G) in the genotype DD in comparison to the genotype CC. Gene interaction effect has significant influence on 6, 8-week-weight and 300-day-weight. The least square analysis showed that individuals with BB genotype of the MyoG gene had higher bodyweight at 2, 4, 10, 12, 14 and 16 weeks compared to individuals with AA and AB genotypes. Individuals with CD genotype of the Myf5 gene had higher birth weight than individuals with CC genotype (P < 0.05). The interactive genotype AB*DD performs well at 6, 8 weeks and 300 days bodyweight. The results suggested that SNPs of the MyoG and Myf5 genes had certain effects on growth traits of the Jinghai yellow chicken.     

Morphological variations in bluegill, Lepomis macrochirus, with particular emphasis on growth-related changes

Morphological variations in bluegill, Lepomis macrochirus, including growth-related changes, sexual dimorphism and morphological differences between populations in different habitats, were examined in samples from three reservoirs in Kagawa, Japan. Body measurements demonstrated frequent growth-related proportional changes, particularly in body depth, body width, caudal peduncle length and head length, which all showed relative increases, whereas first dorsal fin length, caudal fin length and orbital diameter became relatively shorter. Body weight increased relatively with growth, with relative growth coefficients of 3.339–3.454 for regressions between total length and body weight. Such body weight increases were likely due to the relative increases in body depth and width, and caudal peduncle depth. Although counts of fin spines, fin rays and gill rakers did not change with growth, those of scales tended to increase. Males were significantly larger than females in body depth, caudal peduncle length, head length and body weight. Sexual dimorphism was also apparent in body coloration during the breeding season. In addition, a number of morphological differences were observed between individuals from different habitats.     

Novel SNPs in the bovine Transmembrane protein 18 gene, their linkage and their associations with growth traits in Nanyang cattle

Transmembrane protein 18 (TMEM18) gene is expressed in the central nervous system that has recently been linked to human obesity and body mass index (BMI) in genome wide association studies (GWAS). In this study, two novel single nucleotide polymorphisms (SNPs), g.3835 G > A (aa. Gly > Ser) and g.3865 A > G were detected in cattle TMEM18 gene by DNA sequencing. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and forced PCR-RFLP methods were used to genotype the two SNPs in 1218 Chinese native cattle individuals. The association between novel SNPs and growth traits (especially on body weight and body height) in Nanyang cattle showed that individuals with GG genotype was higher than those with AA genotype at g.3835G>A locus (P < 0.05) in Nanyang cattle. Significant association also revealed that individuals of AA genotype at g. 3865 A>G locus were higher in terms of body weight, average daily gain, chest circunmference, body length (P < 0.05), body height and hucklebone width (P < 0.01) than GG genotypes in Nanyang cattle. Moreover, the effect of XspI-MluI combinations with growth traits in Nanyang cattle revealed that AAGG type had higher body weight, body length, chest circumference and average daily gain (P < 0.05) than GGAG in Nanyang cattle aged at 6 months.     

棒花鱼形态特征的两性异形和雌性个体生育力

测定了棒花鱼(Abbottina rivularis)繁殖期形态特征包括体长、头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、胸鳍腹鳍间距、尾柄长、尾鳍长和体重的两性异形和雌性个体生育力。结果表明,雄性个体的数量显著多于雌性个体,雄性个体的体长显著大于雌性个体。特定体长的雌性个体的胸鳍腹鳍间距显著大于雄性个体,头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、尾柄长和尾鳍长显著小于雄性个体,雌雄两性体重不存在显著差异。棒花鱼的怀卵数量与体长和体重回归关系显著。偏相关分析显示,当控制第三者恒定时,怀卵数量与体长和体重呈正相关但不显著。棒花鱼存在个体大小和其他局部特征显著的两性异形,雌性个体主要通过腹腔容积的增加提高个体生育力。棒花鱼形态特征的两性异形是性选择和生育力选择共同作用的结果。     

斑点叉尾GHRH基因3个SNPs位点及其单倍型组合与生长性状的关联分析

研究旨在探讨生长激素释放激素基因（Growth hormone-releasing hormone,GHRH）对斑点叉尾鲖（Ictalurus punctatus）生长性状的影响。采用DNA混池测序法筛选GHRH基因的单核苷酸多态性（Singlenucleotide polymorphisms,SNPs）位点,使用SNaPshot法将筛选到的SNPs多态性位点进行分型,并对这些位点进行连锁不平衡和单倍型分析。结果表明,在GHRH基因内含子区域共检测到4个SNPs位点,并成功地对3个位点进行了分型,3个位点间均不存在强连锁不平衡;3个SNPs位点在176尾斑点叉尾鲖中形成了6种有效单倍型。关联分析表明SNP位点g.6301 GA的AA基因型的体质量显著性地高于AG和GG型（P0.05）,比群体的平均体质量高14%。单倍型组合H1/H4和H1/H5个体的体质量和体长极显著性地高于其他单倍型组合（P0.01）,体质量比群体平均体质量分别高30%和15%,体长比群体平均体长分别高7%和6%。研究为斑点叉尾鲖生长性状分子标记辅助选育和QTL定位提供了参考依据。