Economic Weights for Genetic Changes in Milk Component Yields at the Herd Level
نویسندگان
چکیده
منابع مشابه
Genetic parameters for first lactation milk yields at three levels of herd production.
A multivariate linear model was used to estimate sire variance and covariance components and residual variance components for first lactation milk yield and logarithms of yield at three herd production levels using Restricted Maximum Likelihood with the Expectation-Maximization algorithm. Data for four separate analyses were 305-d, mature equivalent first lactation milk records from cows sired ...
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Chianina is the tallest and heaviest beef cattle breed in the world and 1 of the most appreciated breeds on the Italian meat market. A selection program focused on improving Chianina carcass quality could provide a further economic advantage to Chianina breeders. However, the current European carcass scoring system [i.e., the SEUROP (S=superior, E=excellent, U= very good, R=good, O=fair, and P=...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1990
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(90)78834-0