Department of Animal Science, University of Minnesota, St. Paul 55108, USA.
J Dairy Sci. 2012 Feb;95(2):1011-21. doi: 10.3168/jds.2011-4525.
Pure Holstein (HO) cows (n=416) were compared with Normande (NO) × HO (n=251), Montbéliarde (MO) × HO (n=503), and Scandinavian Red (SR) × HO (n=321) crossbred cows for survival, lifetime production, and profitability in 6 commercial herds in California. The SR crossbred cows were sired by both Swedish Red and Norwegian Red bulls. Cows calved from June 2002 to January 2009. For analysis of survival to subsequent calvings, lifetime production, and profitability, data were restricted to 3 of 6 herds because they had at least 20 cows in each of the breed groups. All cows had the opportunity to calve at least 4 times. Best prediction, which is used by USDA for national genetic evaluations in the United States, was used to determine lifetime production to 4 yr (1,461 d) in the herd after first calving from test-day observations. Production and survival were estimated after 4 yr to calculate lifetime profit. A profit function was defined to include revenues and expenses for milk, fat, protein, and other solids production; somatic cell count; reproduction; feed intake; calf value; salvage value; dead cow disposal; and fixed cost. The NO × HO (1.2%), MO × HO (2.0%), and SR × HO cows (1.6%) had significantly fewer deaths than did pure HO cows (5.3%) during the first 305 d of first lactation. All crossbred groups had significantly more cows that calved a second, third, and fourth time, and had mean survival that was 300 to 400 d longer than did pure HO cows. The NO × HO, MO × HO, and SR × HO cows had significantly higher lifetime fat plus protein production than did pure HO cows up to 1,461 d after first calving. For profitability (ignoring possible differences in health costs), NO × HO cows had 26% greater projected lifetime profit per cow, but 6.7% less profit per cow-day, than did pure HO cows. On the other hand, MO × HO and SR × HO cows had 50 to 44%, respectively, more projected lifetime profit per cow and 5.3 to 3.6%, respectively, more projected profit per cow-day than did pure HO cows.
在加利福尼亚的 6 个商业牛群中，比较了纯种荷斯坦牛（HO）（n=416）与诺曼底牛（NO）×HO（n=251）、蒙贝利亚尔牛（MO）×HO（n=503）和斯堪的纳维亚红牛（SR）×HO（n=321）杂交牛的存活、终生生产和盈利能力。SR 杂交牛由瑞典红牛和挪威红牛公牛配种。牛从 2002 年 6 月至 2009 年 1 月分娩。为了分析后续产犊的存活、终生生产和盈利能力，数据仅限于 6 个牛群中的 3 个，因为每个牛群的品种组都有至少 20 头奶牛。所有奶牛都有机会至少产 4 胎。美国农业部（USDA）在美国全国遗传评估中使用最佳预测来确定首次产犊后的第 4 年（1461 天）的终生生产。在第 4 年之后，根据产奶、脂肪、蛋白质和其他固体生产、体细胞计数、繁殖、饲料摄入、犊牛价值、残值、死牛处理和固定成本的测试日观察结果来估计生产和存活，以计算终生利润。定义了一个利润函数，以包括牛奶、脂肪、蛋白质和其他固体生产、体细胞计数、繁殖、饲料摄入、犊牛价值、残值、死牛处理和固定成本的收入和支出。与纯种 HO 奶牛（5.3%）相比，NO×HO（1.2%）、MO×HO（2.0%）和 SR×HO 奶牛（1.6%）在首次泌乳的前 305 天内死亡的奶牛数量明显更少。所有杂交奶牛组都有更多的奶牛产第二胎、第三胎和第四胎，与纯种 HO 奶牛相比，它们的平均存活时间延长了 300 到 400 天。与纯种 HO 奶牛相比，NO×HO、MO×HO 和 SR×HO 奶牛在首次产犊后 1461 天内的终生脂肪加蛋白质生产显著更高。对于盈利能力（忽略可能存在的健康成本差异），NO×HO 奶牛每头奶牛的预期终生利润增加了 26%，但每头奶牛的利润减少了 6.7%。另一方面，MO×HO 和 SR×HO 奶牛的每头奶牛预期终生利润分别增加了 50%至 44%，每头奶牛的预期利润分别增加了 5.3%至 3.6%。
