First-calving age and first-lactation milk production on Dutch dairy farms
نویسندگان
چکیده
منابع مشابه
Analysis of milk production, age at first calving, calving interval and economic parameters in dairy cattle management
The objective of this study was to evaluate main indicators of milk production on total 60 commercial dairy herds from the Czech Republic during a 9-yr period (2006-2014). Breakeven points and sensitivity analysis were used and associations of age at first calving (AFC), milk yield (MY) and calving interval (CI) were analyzed. Lowest AFC≤749 d showed the highest fertility, the lowest death rate...
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متن کاملCorrelations among first and second lactation milk yield and calving interval.
Estimates of genetic correlations were .17 between first lactation milk yield and concurrent calving interval, .10 between second lactation milk yield and first calving interval, and .82 between first and second milk yields. Corresponding phenotypic correlations were .27, .16, and .58. Heritability estimates were .27 and .25 for first and second lactations and .15 for calving interval. Estimate...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 2013
ISSN: 0022-0302
DOI: 10.3168/jds.2012-5741