终身效益指数(LPI)及近五年加拿大荷斯坦牛群性状遗传增量

终身效益指数是加拿大选择公母牛的主要依据,对提高产奶量和奶品质及牛的强壮度具有重要意义。通过指数选择2010年加拿大的荷斯坦泌乳牛单产已超过9 700kg,乳脂率3.8%,乳蛋白率3.2%,体细胞数低于20万个/mL、细菌数3万以下,真正做到了优质高产。

Lifetime Profit Index（LPI） Bring Inherit Gains to Canadian Holstein in the Last Five Years

Lifetime Profit Index （LPI） is a primary selection tools for bull and cow in Canada, it have important significance to increase mike production, quality and dairy strength. By means of the Index selection, the milking cow yield （305d） in Canada had achieved over 9 700kg, fat rate 3.8%, protein rate 3.2% in 2010. Somatic cell counts was 200 000/mL below, bacterial counts 30 000 below. The dairy herd had realized high quality and high yield. Now, some concerned information would be introduced as follow.