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西夏本三元杂交牛生长发育研究 总被引：1，自引：0，他引：1
测定、分析了西夏本三元杂交牛（公４１头、母３５头）、西黄Ｆ１（公３４头、母３４头）和豫北黄牛（公３４头，母３８头）初生－２４月龄体尺、体重生长发育，结果表明，西夏本杂种牛生长发育快，各月龄体尺、体重显著大于豫北黄牛，比西黄Ｆ１也有明显提高，利用三元杂交进行肉牛生产是一条有效途径。 相似文献
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为了解不同三元杂交组合改良豫北黄牛的效果，对本西夏Ｆ２７６头，本海利６０头，初生，６月龄，１２月龄，２４月龄体重，体尺生长发育进行了测定，分析，结果表明，三元杂交肉牛生长发育迅速，各月龄体重，体尺较豫北黄牛有较大提高。两种三元杂交组合相比，本西夏Ｆ２生长发育较快。 相似文献
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测定、分析了两种三元杂交组合(本夏利F_2:公32头,母30头;本夏西F_2:公母各32头)与豫北黄牛初生——24月龄体重与体尺生长发育。结果表明,三元杂交肉牛生长发育快,体重与体尺在各个月龄下均较本地黄牛有较大幅度提高。利用三元杂交进行肉牛生产是一条有效的途径。两种三元杂交组合相比,本夏西F2较本夏利F_2生长发育迅速。 相似文献
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肉牛三元杂交试验效果研究 总被引：2，自引：0，他引：2
测定分析了四个三元杂交组合（皮西黄F1，♂9头，♀8头；利西黄F1，♂9头，♀8头；短西黄F1，♂7头，♀7头）与当地黄牛初生－18月龄体重和体尺及生长发育，结果表明：以三元杂交肉牛生长发育快，各月龄体重和体尺均较本地黄牛有较大幅度提高，其中以皮西黄牛表现最好，而短西黄牛发育较差。 相似文献
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浅谈牦牛的种间杂交改良问题 总被引：2，自引：0，他引：2
应用三元杂交的方法，将杂种藏黄公牛（黑白花冻精×藏黄牛）与牦牛自然交配，其繁殖成活率达４１．４１％，比用“冻配”技术生产犏牛的繁殖成活率提高２０．８９个百分点，Ｆ１母犏牛第一胎头平产奶量６０３．９ｋｇ，为同胎次母牦牛的２．４３倍。Ｆ１母犏牛２～３岁时可初配，比母牦牛提前１～２岁挤奶。Ｆ１公犏牛３．５岁可役用或屠宰，比阉牦牛提前１～２岁。建议在牦牛分布区，大力推广牦牛的三元杂交。 相似文献
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《中国畜牧兽医文摘》2012,(3)
测定4种三元杂交组合(皮西黄F1,♂8头,♀8头;德西黄F1,♂9头,♀8头;利西黄F1,♂9头,♀8头;短西黄F1,♂7头,♀7头)与当地黄牛初生～18月龄体重和体尺生长发育。结果表明,三元杂交肉牛生长发育快,体重和体尺在各月龄下,均较本地黄牛有较大幅度提高。利用三元杂交进行肉牛生产是一条有效的途径。 相似文献
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豫北黄牛及其杂交改良牛的生长发育研究 总被引：2，自引：2，他引：0
通过测定分析了西利本杂交牛、利本F1杂交牛和豫北黄牛的初生－24月龄体尺、体重指标，结果表明，西利本三元杂交牛生产发育快，各月龄体尺、体重显著大于豫北黄,比利本F1也有显著提高。 相似文献
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豫北黄牛适应性强,耐粗饲,繁殖力旺盛。但是,由于长期饲养管理粗放,牛群未进行系统的选育和合理利用,致使体格较小,生产性能不高,养牛经济效益低。为了充分开发豫北丰富的黄牛资源,提高黄牛利用价值,发展肉牛生产,我们利用肉牛冷冻颗粒精液与豫北黄牛进行了杂交改良试验,现将试验结果报告于后。 1 材料与方法 1.1 研究材料选取1985年出生的犊牛344头,其中西黄F_168头(公、母各34头),夏黄F_182头(公42头、母40头),利黄F_168头(公32头,母36头),海黄F_166 相似文献
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为了研究青海省肉牛杂交改良效果,筛选适应高寒地区肉牛最佳杂交组合,从而为今后开展肉牛杂交工作提供有力的依据,通过6年的试验研究,测定分析了蓝本、皮本、利本、夏本、德本F1牛和青海黄牛的初生,3月龄,6月龄,12月龄,18月龄体重及体尺指标及杂交后代对青海高原高寒气候的适应性观察。结果显示:五个杂交组合F1代不同年龄的生长速度和体尺指标均明显优于青海黄牛(P<0.01)说明良种肉牛改良效果显著,在不同杂交组合后代的比较中,蓝本F1牛生长发育最快,各阶段体重及体尺指标显著高于青海黄牛,比皮本、利本、夏本、德本F1牛也有明显提高。 相似文献
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Estimation of additive and nonadditive genetic variances in Hereford, Gelbvieh, and Charolais by Method R. 总被引：3，自引：0，他引：3
Parameters for direct and maternal dominance were estimated in models that included non-additive genetic effects. The analyses used weaning weight records adjusted for age of dam from populations of Canadian Hereford (n = 467,814), American Gelbvieh (n = 501,552), and American Charolais (n = 314,552). Method R estimates of direct additive genetic, maternal additive genetic, permanent maternal environment, direct dominance, and maternal dominance variances as a proportion of the total variance were 23, 12, 13, 19, and 14% in Hereford; 27, 7, 10, 18, and 2% in Gelbvieh; and 34, 15, 15, 23, and 2% in Charolais. The correlations between direct and maternal additive genetic effects were -0.30, -0.23, and -0.47 in Hereford, Gelbvieh, and Charolais, respectively. The correlations between direct and maternal dominance were -0.38, -0.02, and -0.04 in Hereford, Gelbvieh, and Charolais, respectively. Estimates of inbreeding depression were -0.20, -0.18, and -0.13 kg per 1% of inbreeding for Hereford, Gelbvieh, and Charolais, respectively. Estimates of the maternal inbreeding depression were -0.01, -0.02, and -0.02 kg, respectively. The high ratio of direct dominance to additive genetic variances provided some evidence that direct dominance effects should be considered in beef cattle evaluation. However, maternal dominance effects seemed to be important only for Hereford cattle. 相似文献
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本研究把夏南杂交的正回交后代、反回交后代及南阳牛的体重、体尺作了比较分析。结果表明，初生、6、12、18及24月龄，正、反回交后代公、母牛平均体重均高于同龄同性别南阳牛，差异均极显著，正回交公牛与反回交公牛相比，平均初生重差异不显著；6、12、18月龄反回交公牛平均体重明显高于正回交公牛，差异均极显著，24月平均体重差异不显著；正回交母牛与反回交母牛相比，反回交母牛平均初生体重高于正回交母,两者差异显著，但6、12、18及24月龄平均体重差异不显著。 相似文献
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Genetic relationships between calving and carcass traits for Charolais and Hereford cattle in Sweden 总被引：1，自引：0，他引：1
The objective of this study was to estimate genetic correlations between calving difficulty score and carcass traits in Charolais and Hereford cattle, treating first and later parity calvings as different traits. Genetic correlations between birth weight and carcass traits were also estimated. Field data on 59,182 Charolais and 27,051 Hereford calvings, and carcass traits of 5,260 Charolais and 1,232 Hereford bulls, were used in bivariate linear animal model analyses. Estimated heritabilities were moderate to high (0.22 to 0.50) for direct effects on birth weight, carcass weight, and (S)EUROP (European Community scale for carcass classification) grades for carcass fleshiness and fatness. Heritabilities of 0.07 to 0.18 were estimated for maternal effect on birth weight, and for direct and maternal effects on calving difficulty score at first parity. Lower heritabilities (0.01 to 0.05) were estimated for calving difficulty score at later parities. Carcass weight was positively genetically correlated (0.11 to 0.53) with both direct and maternal effects on birth weight and with direct effects on calving difficulty score. Carcass weight was, however, weakly or negatively (-0.70 to 0.07) correlated with maternal calving difficulty score. Higher carcass fatness grade was genetically associated with lower birth weight, and in most cases, also with less difficult calving. Genetic correlations with carcass fleshiness grade were highly variable. Moderately unfavorable correlations between carcass fleshiness grade and maternal calving difficulty score at first parity were estimated for both Charolais (0.42) and Hereford (0.54). This study found certain antagonistic genetic relationships between calving performance and carcass traits for both Charolais and Hereford cattle. Both direct and maternal calving performance, as well as carcass traits, should be included in the breeding goal and selected for in beef breeds. 相似文献
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Genetic parameters for calving difficulty, stillbirth, and birth weight for Hereford and Charolais at first and later parities 总被引：1，自引：0，他引：1
The aim of this study was to estimate direct and maternal genetic parameters for calving difficulty score, stillbirth, and birth weight at first and later parities for Charolais and Hereford cattle in Sweden. Calving traits have long been recorded for pure-bred beef cattle in Sweden, but only birth weight has been used in the selection in order to avoid calving difficulties. Linear animal model analyses included records on birth weight for 60,309 Charolais and 30,789 Hereford calves born from 1980 to 1999, and calving traits for 74,538 Charolais and 37,077 Hereford calves born from 1980 to 2001. The frequencies of difficult calvings and stillbirths were approximately 6% at first and 1 to 2% at later parities for both breeds. Fewer than half the stillborn calves were born from difficult calvings. Heritabilities estimated for birth weight in different univariate and bivariate analyses for Charolais and Hereford calves born at first and later parities ranged from 0.44 to 0.51 for direct effects and 0.06 to 0.15 for maternal effects. Heritabilities on the observable scale for calving difficulty score of Charolais and Hereford, scored in three classes, ranged from 0.11 to 0.16 for direct and 0.07 to 0.12 for maternal effects at first parity, and lower at later parities. All estimated heritabilities for stillbirth were very low (0.002 to 0.016 on the observable scale). Direct-maternal genetic correlations were negative, with few exceptions. Genetic correlations between the traits and between parities within traits were generally moderate to high and positive. Calving difficulty score should be included in the genetic evaluation of beef breeds in Sweden, whereas progeny groups in Swedish beef populations are too small for stillbirth to be considered directly. 相似文献
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为了筛选适合贵州生产的三元杂交肉牛,试验选用利木赞牛、安格斯牛和夏洛莱牛冻精对西本母牛进行杂交改良.试验结果表明：不同杂交组合后代犊牛均表现出明显的杂种优势,从初生到18月龄,夏西本牛的体重、体尺指标均最优,依次为利西本牛、安西本牛、西本杂牛;3组三元杂交牛不同月龄的体重、体尺指标均差异不显著（P＞0.05）,但均显著高于西本杂牛（P＜0.05）.结论：虽然夏西本牛的体尺指标和生产性能最好,但由于其产犊难产比例较高,且当地养殖户不喜欢其白色的被毛,因此建议在本省推广利西本牛、安西本牛. 相似文献