Contemporary Groups for Genetic Evaluations
نویسندگان
چکیده
منابع مشابه
Contemporary groups for genetic evaluations.
Contemporary groups are used to remove biases from genetic evaluations due to differential effects such as management associated with the grouping. Numerous groups, however, can result in small numbers of records per subclass with associated loss of effective number of daughters for sire evaluation and increased prediction error variance. Thus, in practice, mean square error, bias squared plus ...
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Accuracy and bias of EBV are important measures of the quality of genetic evaluations. A sampling method that accounts for the uncertainty in the estimation of genetic group effects was used to calculate accuracy and bias of estimated effects. The method works by repeatedly simulating phenotypes for multiple traits for a defined data and pedigree structure. These simulated values are analyzed u...
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Currently in Australia, there are two main ways to compare animals from different herds. The first is to buy animals or semen from other breeders and test their progeny on-farm against "home-bred" animals. The second is to enter animals in a central testing facility, such as WACOL, SABOR or TOCAL. Both of these methods can be subject to sampling problems or, in other words, chance, that can aff...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1987
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(87)80309-0