Pérez-Cabal M A, Alenda R
Departamento de Producción Animal, E.T.S.I. Agrónomos-Universidad Politécnica, Ciudad Universitaria s/n 28040 Madrid, Spain.
J Dairy Sci. 2003 Dec;86(12):4115-22. doi: 10.3168/jds.S0022-0302(03)74025-9.
Genetic parameters for lifetime profit and some productive traits were estimated from records of 42,401 Holstein cows with first calving before May 1996 from Navarra and Basque Autonomous Regions of Spain. Profit from the first, first two, and first three lactations were tested as early measures of profitability. Profit prediction was tested for another population of 2127 cows using selection indexes (Type-Production and economic indexes) and multitrait analysis for directly predicting profit from first-lactation records. High genetic correlations of actual profit with estimated profit from the first two or first three lactation records, (0.97 and 0.99, respectively) suggest that lifetime profit can be accurately estimated from data in second lactation. Profit was positively correlated to production traits (0.79 to 0.83), functional herd life (0.38), mature body weight (0.25), and days in milk (0.35), but genetic correlation was found to be close to zero with calving interval. Complicated relationships among profit and economic traits (i.e., calving interval, days in milk, and functional herd life) were found. Although the correlation between calving interval and profit was near zero, calving interval was the most important trait after production in prediction of sire profit by a stepwise regression analysis. Profit breeding values from multitrait analysis obtained higher correlation (0.48) with actual profit than Spanish official Type-Production index ICO (0.44) and economic index MEG (0.46). A correlation of 0.49 between profit breeding values and the economic index MEG2002, where stature and calving interval were included as new traits, was obtained.
利用西班牙纳瓦拉和巴斯克自治区1996年5月前首次产犊的42401头荷斯坦奶牛的记录,估计了终身利润和一些生产性状的遗传参数。将第一次、前两次和前三次泌乳的利润作为盈利能力的早期衡量指标进行了测试。使用选择指数(体型-生产指数和经济指数)和多性状分析,对另一群体的2127头奶牛进行了利润预测,以直接根据第一次泌乳记录预测利润。实际利润与前两次或前三次泌乳记录估计利润的高遗传相关性(分别为0.97和0.99)表明,可以根据第二次泌乳的数据准确估计终身利润。利润与生产性状(0.79至0.83)、功能性牛群寿命(0.38)、成熟体重(0.25)和泌乳天数(0.35)呈正相关,但发现与产犊间隔的遗传相关性接近零。发现利润与经济性状(即产犊间隔、泌乳天数和功能性牛群寿命)之间存在复杂关系。尽管产犊间隔与利润之间的相关性接近零,但在逐步回归分析预测父系利润时,产犊间隔是仅次于生产性状的最重要性状。多性状分析得到的利润育种值与实际利润的相关性(0.48)高于西班牙官方体型-生产指数ICO(0.44)和经济指数MEG(0.46)。利润育种值与经济指数MEG2002之间的相关性为0.49,其中将体高和产犊间隔作为新性状纳入其中。