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正通过西藏高原特色、绿色、无污染等优势,形成强大的带动力,创造更大的市场发展空间。一、西藏黄牛改良总体情况1.西藏黄牛产地、环境及分布。西藏黄牛分布在以种植业为主的地区,即农区、林区和半农半牧区。海拔2300~3800米地区。主要分布在西藏自治区的拉萨、堆龙、曲水、尼木、墨竹工卡、林芝、波密、乃东、桑日、朗县、加查、洛扎、错那、昌都、察隅、日喀则的农区、半农半牧区等地。2.黄牛改良发展现状。西藏黄牛在西藏的发展具有悠久的历史, 相似文献
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西藏黄牛改良从1979年开始,科技工作者应用先进的"品种基因选择"、"不同品种的组合运用"、"牛冷冻精液人工授精"等生物技术,经改进、组装、配套,保留了"京×藏""西×藏""娟×藏"3个杂交组合方案,并结合西藏的实际现状,经过30多年的转化推广应用,改变了西藏黄牛季节性发情的遗传性,由原3年两胎转变为1年1胎。黄牛改良研究成果,成功地克服并首次解决了西藏高寒生态条件下家畜引种不适应的重大技术难题,取得了巨大的经济、社会、生态效益。西藏黑白花牛在高寒生态条件下的适应能力仅次于西藏黄牛,可以在海拔4200m地区生存生产,为培育"西藏乳用黑白花牛"开创了有实际应用价值的新模式。 相似文献
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针对西藏黄牛个体小、成熟晚、生产性能低的缺陷,研究人员于1979年开始采用新技术、新方法,引进先进的“冻配”人工授精技术,经配套、组装和改进,形成以“冻配”为主的综合配套技术,对西藏黄牛改良和杂交育种进行定性、定量、定位的研究。首次彻底解决了在西藏高寒生态条件下家畜引种不适应的重大难题;为“西藏乳用牛新品种”开创了有实际应用价值的新模式:在研究和生产应用中首次突破了国内外家畜改良的海拔高度-202m;研究成果改变了西藏黄牛季节性发情的遗传性,加快了黄牛改良和杂交育种进度,扩大了改良范围,丰富了遗传基因,取得了很大的经济、社会和生态效益。 相似文献
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随着科学技术的发展,我国的畜牧业对畜种进行改良的技术也得到了进一步的发展与应用.昭阳区采用冻精改良技术对昭通黄牛进行配种改良,并将这项技术向全区进行推广应用,取得了较好的经济效益和社会效益. 相似文献
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巴山黄牛品种形成已有千余年历史,主要分布于陕、川、渝、鄂四省市的巴山地区及秦岭山脉的部分地区,1982年已编入陕西省畜禽品种志,并被列入省级地方品 相似文献
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Antonio Reverter Brad C Hine Laercio Porto-Neto Yutao Li Christian J Duff Sonja Dominik Aaron B Ingham 《Journal of animal science》2021,99(3)
In animal breeding and genetics, the ability to cope with disease, here defined as immune competence (IC), with minimal detriment to growth and fertility is a desired objective which addresses both animal production and welfare considerations. However, defining and objectively measuring IC phenotypes using testing methods which are practical to apply on-farm has been challenging. Based on previously described protocols, we measured both cell-mediated immune response (Cell-IR) and antibody-mediated immune response (Ab-IR) and combined these measures to determine an animal’s IC. Using a population of 2,853 Australian Angus steers and heifers, we compared 2 alternative methods to combine both metrics into a single phenotype to be used as a tool for the genetic improvement of IC. The first method, named ZMEAN, is obtained by taking the average of the individual metrics after subjecting each to a Z-score standardization. The second, ImmuneDEX (IDEX), is a weighted average that considers the correlation between Cell-IR and Ab-IR, as well as the difference in ranking of individuals by each metric, and uses these as weights in the averaging. Both simulation and real data were used to understand the behavior of ZMEAN and IDEX. To further ascertain the relationship between IDEX and other traits of economic importance, we evaluated a range of traits related to growth, feedlot performance, and carcass characteristics. We report estimates of heritability of 0.31 ± 0.06 for Cell-IR, 0.42 ± 0.06 for Ab-IR, 0.42 ± 0.06 for ZMEAN and 0.370 ± 0.06 for IDEX, as well as a unity genetic correlation (rg) between ZMEAN and IDEX. While a moderately positive rg was estimated between Cell-IR and Ab-IR (rg = 0.33 ± 0.12), strongly positive estimates were obtained between IDEX and Cell-IR (rg = 0.80 ± 0.05) and between IDEX and Ab-IR (rg = 0.85 ± 0.04). We obtained a moderately negative rg between IC traits and growth including an rg = −0.38 ± 0.14 between IDEX and weaning weight, and negligible with carcass fat measurements, including an rg = −0.03 ± 0.12 between IDEX and marbling. Given that breeding with a sole focus on production might inadvertently increase susceptibility to disease and associated antibiotic use, our analyses suggest that ImmuneDEX will provide a basis to breed animals that are both highly productive and with an enhanced ability to resist disease. 相似文献
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