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Use of progeny testing in beef cattle: prediction of genetic gain in a Nelore Cattle Breeding Program

Henrique Nunes de Oliveira^II; Raysildo Barbosa Lôbo^II

^IDepartamento de Melhoramento e Nutrição Animal, Faculdade de Medicina Veterinária e Zootecnia, UNESP, 18610-000 Botucatu, SP, Brasil. Send correspondence to H.N.O.
^IIDepartamento de Genética, Faculdade de Medicina de Ribeirão Preto, USP, 14049-900 Ribeirão Preto, SP, Brasil

ABSTRACT

Genetic gains predicted for selection, based on both individual performance and progeny testing, were compared to provide information to be used in implementation of progeny testing for a Nelore cattle breeding program. The prediction of genetic gain based on progeny testing was obtained from a formula, derived from methodology of Young and Weiler (J. Genetics 57: 329-338, 1960) for two-stage selection, which allows prediction of genetic gain per generation when the individuals under test have been pre-selected on the basis of their own performance. The application of this formula also allowed determination of the number of progeny per tested bull needed to maximize genetic gain, when the total number of tested progeny is limited.

Keywords: progeny testing; beef cattle; genetic gain; Nelore.

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