奶牛选种选配的工作实践

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为提高奶牛的生产性能和遗传品质,海燕畜牧公司奶牛二场自1998年开始,在畜牧公司的统一领导下,借助天津市奶牛发展中心专家的力量,全面展开了牛群改良的选种选配工作。通过几年的不懈努力,到2003年牛群年单产由5483kg提高到7385kg,平均乳脂率3.5%,乳蛋白率从2.25%提高到3.02%。现将几年
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