Genetic parameters for test day milk yields of first lactation Holstein cows by random regression models
نویسندگان
چکیده
منابع مشابه
Genetic parameters for first lactation test-day milk flow in Holstein cows.
Genetic parameters for test-day milk flow (TDMF) of 2175 first lactations of Holstein cows were estimated using multiple-trait and repeatability models. The models included the direct additive genetic effect as a random effect and contemporary group (defined as the year and month of test) and age of cow at calving (linear and quadratic effect) as fixed effects. For the repeatability model, in a...
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ژورنال
عنوان ژورنال: Animal
سال: 2007
ISSN: 1751-7311
DOI: 10.1017/s1751731107685036