منابع مشابه
Genetic Parameters for Production Traits of Holsteins in California, New York, and Wisconsin
Heritabilities and genetic correlations were estimated for milk and fat yields and fat percentage from 305-d, matureequivalent records of registered and grade Holsteins in California, New York, and Wisconsin. Parameter estimates were olytained with daughter on dam regression within herd-year-season and sire of daughter. Data were pairs of first lactation records (38,115 in California, 171,555 i...
متن کاملModeling extended lactations of Holsteins.
Modeling extended lactations for the US Holsteins is useful because a majority (>55%) of the cows in the present population produce lactations longer than 305 d. In this study, 9 empirical and mechanistic models were compared for their suitability for modeling 305-d and 999-d lactations of US Holsteins. A pooled data set of 4,266,597 test-day yields from 427,657 (305-d complete) lactation recor...
متن کاملAnimal model evaluations for Mexican Holsteins.
Genetic evaluations for milk yield of Holsteins in Mexico were computed from lactation and pedigree information from Holstein de México. The US animal model system for national evaluations was adapted for Mexico. The primary change was in defining unknown-parent groups. Paths of unknown parents of bulls and sires of cows were combined and separate unknown-parent groups defined for parents of US...
متن کاملHolsteins are the genomic selection poster cows.
Genomic selection (GS) is the process by which the genetic improvement of plants or animals is accomplished using the genomic prediction (GP) of additive genetic merits [known as genomic estimated breeding values (GEBVs)] of selection candidates. Alternative statistical models for GP were first described in 2001 by Meuwissen et al. (1), who used simulation to evaluate the performance of linear ...
متن کاملDiet energy requirements of growing Holsteins.
The conceptual bases of recent NRC publications of nutrient requirements to meet dietary energy needs of growing Holsteins, emphasizing heifers gaining 0.75 kg/d, are described and compared with several world systems and with body composition data. Requirements of Holsteins for net energy for maintenance are generally thought to be higher (from 7 to 20%) than those of British beef breeds. Total...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Scientific American
سال: 1904
ISSN: 0036-8733
DOI: 10.1038/scientificamerican04301904-23689asupp