共查询到18条相似文献，搜索用时 171 毫秒
1.
利用8个微卫星标记测定半番鸭亲本间的遗传距离,并分析了亲本遗传距离与半番鸭主要经济性状的相关关系.结果表明：亲本间微卫星标记遗传距离与杂交后代日增重相关程度较高,相关系数0.9285～0.9978;与饲料转化率呈负相关关系,相关系数-0.7838～-0.8965;与10周龄的半净膛率和全净膛率呈正相关,相关系数0.9094和0.8838;与胸肌率、皮脂率和腹脂率也呈强正相关,相关系数0.9027、0.9378和0.7983,与腿肌率则呈强负相关,相关系数-0.8898. 相似文献
2.
3.
黄羽肉鸡群体遗传变异的微卫星分析及其与体重杂种优势的关系 总被引：3，自引：0，他引：3
选用10对微卫星引物分析了黄羽肉鸡A、B、C3个品系的遗传结构和差异,并对微卫星标记所计算的个体间遗传距离与C×B、C×A杂交后代的初生至8周龄体重的杂种优势和杂种优势率进行了相关分析。结果表明,10个微卫星标记中有9个表现出多态性,多态信息含量(PIC)和群体杂合度(Heterozigosity)分别为0·4400和0·6811,各品系、各微卫星基因座上都表现出一定差异。利用9个多态微卫星标记计算得出的亲本个体间的遗传距离与后代杂种优势率间多数没有显著的相关(P>0·05),仅C×B组合中亲本个体间平均遗传距离与第8周龄体重杂种优势和杂种优势率间相关显著(P<0·05)。 相似文献
4.
5.
肉牛杂交亲本遗传距离与杂种优势的相关性研究 总被引：2，自引：0，他引：2
利用11个微卫星标记研究川南山地黄牛、海福特牛、黑安格斯牛、红安格斯牛、利木赞牛、西门塔尔牛、德国黄牛的遗传多样性,分析肉牛亲本间微卫星标记遗传距离与体尺、体重杂种优势间的相关性。结果表明:11个微卫星基因座平均有效等位基因数为4.5422,7个牛种的多态信息含量在0.3434~0.4207,平均杂合度为0.6868~0.8413,7个牛种均具有丰富的多态性。亲本间遗传距离与体尺、体重杂种优势间相关系数偏小(-0.003~0.304),均未达到显著水平,用微卫星标记遗传距离预测肉牛体尺、体重杂种优势还有待进一步探讨。 相似文献
6.
通过6对微卫星DNA标记对湘西黄牛及其与安格斯、夏洛来、利木赞和西门塔尔牛的杂交牛进行了遗传多样性分析,以期了解湘西黄牛及其杂交牛的群体遗传结构和育成情况.通过计算多态信息含量(PIC)、平均杂合度(H),评估湘西黄牛遗传变异和各杂交品种间遗传相关.结果表明,6个微卫星座位共检测到52个等位基因,平均等位基因数为8.67个;6个微卫星座位的多态信息含量在0.6858～0.8576间.表现出较为丰富的信息含量;4个杂交品种与湘西黄牛之间的遗传距离为0.1620～0.2554;杂交牛与湘西黄牛间遗传距离与杂种优势率的相关系数为0.9142,平均基因杂合度与杂种优势率的相关系数为0.8517,呈高度正相关.结果表明,有效微卫星标记的利用能有效的测定湘西黄牛杂交牛的遗传多样性,提高其生产性能. 相似文献
7.
利用扩增片段长度多态性(AFLP)标记,测定6个亲本群体间的遗传距离,并对亲本群体间遗传距离与6个经济性状的杂种优势率相关关系进行分析。结果表明:亲本间遗传距离与日增重、饲料转化率、屠宰率和平均背膘厚的杂种优势率呈正相关,与瘦肉率、眼肌面积的杂种优势率呈负相关;亲本群间AFLP标记遗传距离与杂种优势的相关程度因性状不同而异。 相似文献
8.
家蚕亲本遗传距离与杂种优势和特殊配合力的关系 总被引：2，自引：0，他引：2
采用Griffing交配设计,对56个家蚕杂交组合及其8个亲本进行比较试验,探索家蚕亲本遗传距离与F_1产量的杂种优势与组合特殊配合力的关系。结果表明:亲本遗传距离与杂种优势、遗传距离与特殊配合力均呈极显著的直线回归关系。杂种优势与特殊配合力之间高度一致。用双亲遗传距离在一定程度上能预测家蚕F_1产量的杂种优势和特殊配合力。用双亲平均值和遗传距离的二元回归法预测,效果比一元回归法更好。 相似文献
9.
对不同鸭品种,即绍兴鸭、西湖野鸭和慈溪绿头野鸭,以及绍兴鸭与西湖野鸭、慈溪绿头野鸭的2个杂交组合的F1代进行肉用性能测定比较分析,各个组合选10只成年鸭。结果表明,绍兴鸭与绿头野鸭的杂交F1代在全净膛率、瘦肉率、胸肌嫩度和腿肌pH值4个指标上表现不同程度的杂种优势,而绍兴鸭与西湖野鸭的杂交F1代则在半净膛重、全净膛重、胸肌重、瘦肉重、全净膛率、瘦肉率和腿肌嫩度这7个指标上表现不同程度的杂交优势;而且,绍兴鸭与西湖野鸭的杂交效果在屠宰性能上,尤其是胸肌重、瘦肉重、全净膛率和瘦肉率较好,这4个性状的杂交优势率分别达到60.300%,20.241%,12.743%,19.999%,可以作为野鸭生产的一个配套商品组合。 相似文献
10.
《养禽与禽病防治》2017,(4)
以欧洲肉鸽Ⅱ系、白卡奴鸽、欧洲肉鸽Ⅱ系♂×白卡奴♀杂交F1代为研究对象,随机选取28日龄乳鸽各40只进行体尺及屠宰测定,探讨F1代获得杂交优势情况。结果显示,F1代体斜长、龙骨长、胸宽均显著高于母本水平(P0.05),胫长显著低于两亲本水平(P0.05),胫围超过了两亲本水平,与母本之间达到显著性差异(P0.05);F1代的体斜长、龙骨长、胫围存在杂交优势率,分别为3.17、4.60和9.24;F1代活体重、屠体重、半净膛重、全净膛重、腹脂重、胸肌重、腿肌重、胸肌率和腿肌率均显著高于母本水平(P0.05),半净膛率和全净膛率显著高于父本水平(P0.05),F1代的半净膛重、全净膛重、全净膛率和半净膛率存在杂交优势率,分别为0.36、0.41、4.66和4.75。综上所述,F1代鸽体型较大,杂交后肉用性能得到提升,欧洲肉鸽Ⅱ系♂×白卡奴♀杂交效果良好。 相似文献
11.
By F. Minvielle J. -L. Monvoisin J. Costa A. Frenot Y. Maeda 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1999,116(5):363-377
In much animal production, commercial animals are crossbreds from closed lines or breeds under long-term directional selection. Therefore it is desirable to be able to predict heterosis gains over the generations as it is done for genetic progress under within-line selection. However, heterosis is the phenotypic expression of a complex phenomenon which may involve several types of genetic effects like dominance and epistasis. In animal breeding, basic quantitative genetics theory indicates that heterosis should be proportional to (squared) differences in gene frequency between populations (e.g. F alconer and M ac K ay 1996), and it has been found approximately correct, so it is commonly used for planning crosses. Under that type of heterosis, however, selection towards the same objective in two populations should bring gene frequencies closer, and therefore it should eventually decrease heterosis. On the other hand, reciprocal recurrent selection designed to increase genetic distance between lines should eventually achieve maximum heterosis (O llivier 1982). Some experiments reviewed by brun (1982) have already compared genetic progress under within-line and reciprocal recurrent selection, but they did not focus on comparing the trend of heterosis with generations between the two selection methods. Also, heterosis was monitored periodically in some selection experiments on poultry, and results were reviewed by F airfull (1990). They were somewhat contradictory, but they generally failed to relate genetic progress to loss of heterosis under within-line selection. Moreover, in commercial production, as purebreds and crossbreds are not contemporaries and are generally maintained under very different management systems, estimations of heterosis and of the evolution of crossbred advantage over the generations may be difficult to obtain. Using the Japanese quail as an experimental animal, the present work was initiated specifically to follow the changes in heterosis brought about by selection for a single heterotic trait, early egg production (M invielle et al. 1995). For that purpose, two selection methods expected to have opposite effects on heterosis, directional within-line (or individual) selection and reciprocal recurrent selection, were applied for 13 generations in four quail lines started from two different origins, and trends of heterosis in the selected character and in weight and egg traits were evaluated. 相似文献
12.
三个鸡品系的遗传差异与杂种优势关系的研究 总被引：1，自引：0，他引：1
采用RAPD标记分析了武定鸡快羽系、绿壳蛋系和合成系间的遗传差异,进行了三个鸡品系间的杂交试验,并应用简单的线性相关分析了遗传距离指数与杂种优势的关系。分析结果表明快羽系与绿壳蛋系间的遗传差异较小,而快羽系与合成系间的遗传差异较大。品系间遗传距离指数与F1代各性状观察值均为正相关,但相关不显著;与杂种优势率之间也均为正相关,但只与13周龄存活率、种蛋受精率有显著的相关关系。表明RAPD标记在预测杂种优势上具有一定参考价值。 相似文献
13.
Published information on relative performance of beef breed crosses was used to derive combined estimates of purebred breed values for predominant temperate beef breeds. The sources of information were largely from the United States, Canada, and New Zealand, although some European estimates were also included. Emphasis was on maternal traits of potential economic importance to the suckler beef production system, but some postweaning traits were also considered. The estimates were taken from comparison studies undertaken in the 1970s, 1980s and 1990s, each with representative samples of beef breeds used in temperate agriculture. Weighting factors for breed-cross estimates were derived using the number of sires and offspring that contributed to that estimate. These weights were then used in a weighted multiple regression analysis to obtain single purebred breed effects. Both direct additive and maternal additive genetic effects were estimated for preweaning traits. Important genetic differences between the breeds were shown for many of the traits. Significant regression coefficients were estimated for the effect of mature weight on calving ease, both maternal and direct additive genetic, survival to weaning direct, and birth weight direct. The breeds with greater mature weight were found to have greater maternal genetic effects for calving ease but negative direct genetic effects on calving ease. A negative effect of mature weight on the direct genetic effect of survival to weaning was observed. A cluster analysis was done using 17 breeds for which information existed on nine maternal traits. Regression was used to predict breed-cross-specific heterosis using genetic distance. Only five traits, birth weight, survival to weaning, cow fertility, and preweaning and postweaning growth rate had enough breed-cross-specific heterosis estimates to develop a prediction model. The breed biological values estimated provide a basis to predict the biological value of crossbred suckler cows and their offspring. 相似文献
14.
15.
旨在利用覆盖全基因组和性状的特异性SNPs标记预测和牛、西门塔尔牛与荷斯坦牛杂种优势,为牛杂种优势利用和选种选配提供参考依据。本研究分别利用牛Illumina Bovine HD 770 K和GGP Bovine 100 K芯片对464头和牛、1 222头西门塔尔牛和43头荷斯坦牛3个亲本群体进行基因型分型,并通过牛QTLs数据库筛选与目的性状对应的QTLs,对比牛参考基因组映射得到与初生重、周岁重、胴体重性状相关的特异性SNPs;然后构建覆盖全基因组和性状特异性SNPs两种标记状态同源矩阵,通过计算杂交组合亲本间的遗传距离来预测品种间杂种优势,并利用配合力分析验证较优组合的实际杂交效果。结果表明,基于全基因组和性状特异性SNPs计算的各杂交组合遗传距离差异不显著。在全基因组水平上,西门塔尔牛♂×荷斯坦牛♀（S×H）与和牛♂×荷斯坦牛♀（W×H）亲本间杂交组合遗传距离分别为0.346 1和0.338 9;在初生重、周岁重和胴体重性状上,S×H亲本间遗传距离分别为0.343 1、0.348 7和0.336 7,而W×H遗传距离分别为0.337 6、0.340 7和0.329 2;两种SNPs标记计算的遗传距离均为S×H较大,W×H次之。因此,在初生重、周岁重、胴体重性状上,S×H为较优杂交组合。通过分析德系西门塔尔牛♂×荷斯坦牛♀实际杂交群体的配合力,发现10个父系在初生重性状上一般配合力和特殊配合力均为正效应,最高效应值分别达到3.760 9和8.931 2。西门塔尔牛与荷斯坦牛杂交可在初生重、周岁重和胴体重获得较高的杂种优势。 相似文献
16.
旨在利用覆盖全基因组和与性状相关的SNPs标记分析西门塔尔牛和地方黄牛两个亲本群体的遗传结构,通过亲本种群之间的遗传距离预测不同杂交组合在生长、胴体和肉质性状上的杂种优势。本研究选择来自内蒙古锡林郭勒盟乌拉盖管理区牧场的1 222头西门塔尔牛和8个地方黄牛品种190头共组成8个杂交组合,对亲本群体进行遗传结构分析。利用牛770K SNP芯片对两个亲本群体进行基因型分型,通过牛QTL数据库筛选与目的性状对应的QTLs,对全基因组SNP位点进行映射分析得到与性状相关的SNP标记。利用两种SNP标记构建状态同源矩阵,计算各杂交组合亲本间的遗传距离。结果,所有亲本群体聚成3类,西门塔尔牛聚成一类,北方黄牛（蒙古牛、西藏牛和柴达木牛）聚成一类,南方黄牛（昭通牛、平武牛、南丹牛、文山牛和凉山牛）聚成一类。西门塔尔牛与北方黄牛在PCA图上的距离较近,说明两者之间亲缘关系相对较近,遗传背景差异较小。在各性状中,遗传距离最大的亲本组合都是西门塔尔牛与南丹牛杂交组合。除了大理石花纹评分性状是西门塔尔牛与昭通牛之间的遗传距离最小,其余性状遗传距离最小的亲本组合都是西门塔尔牛与平武牛杂交组合。据此推测,各性状杂种优势较优的可能组合是西门塔尔牛与南丹牛杂交组合。 相似文献
17.
M. Penasa N. López‐Villalobos R.D. Evans A.R. Cromie R. Dal Zotto M. Cassandro 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2010,127(4):300-307
The aim of the study was to assess crossbreeding effects for 305‐day milk, fat, and protein yield and calving interval (CI) in Irish dairy cows (parities 1 to 5) calving in the spring from 2002 to 2006. Data included 188 927 records for production traits and 157 117 records for CI. The proportion of genes from North American Holstein Friesian (HO), Friesian (FR), Jersey (JE) and Montbéliarde (MO) breeds, and coefficients of expected heterosis for HO×FR, HO×JE and HO×MO crosses were calculated from the breed composition of cows’ parents. The model used to assess crossbreeding effects accounted for contemporary group, age at calving within parity, linear regression on gene proportions for FR, JE and MO, and linear regression on coefficients of expected heterosis for HO×FR, HO×JE and HO×MO, as fixed effects, and additive genetic, permanent environmental and residual as random. Breed effects for production traits were in favour of HO, while for CI were in favour of breeds other than HO. The highest heterosis estimates for production were for HO×JE, with first‐generation crosses yielding 477 kg more milk, 25.3 kg more fat, and 17.4 kg more protein than the average of the parental breeds. The highest estimate for CI was for HO×MO, with first‐generation crosses showing 10.2 days less CI than the average of the parental breeds. Results from this study indicate breed differences and specific heterosis effects for milk yield traits and fertility exist in Irish dairy population. 相似文献