Selection response for milk production in conventional production systems in Mexico, using genetic evaluations of Holstein sires from Canada and the United States
Por:
Montaldo H.H., Nunez-Soto, SG, Ruiz-López F.J., Castillo-Juárez H.
Publicada:
1 oct 2009
Resumen:
Polynomial regression models of the first, second, and third order were used to fit milk production deviations of daughters in Mexico on Canadian and US predicted transmitting ability values for 305-d mature-equivalent milk production (kg). For the pairs Canada-Mexico and Mexico-United States, 40 and 73 bulls with a minimum reliability of 0.75 were analyzed, respectively. Genetic correlations between pairs of countries were also estimated. The parameters were evaluated for all data, and for sires grouped according to the mean of the average phenotypic milk production (high and low) of their daughters' herd mates. Quadratic and cubic effects were not significant in any analysis. From linear regression models, slopes of Mexican daughter deviations on US and Canadian predicted transmitting abilities were 1.01 and 0.93, respectively. Slopes were greater but intercepts were smaller for the high versus low level of production of the sires' herd mates in Mexico. A greater difference between t
Filiaciones:
Montaldo H.H.:
Univ Nacl Autonoma Mexico, Dept Genet & Bioestadist, Fac Med Vet & Zootecnia, Mexico City 04510, DF, Mexico
Ruiz-López F.J.:
Centro Nacional de Investigación en Fisiología y Mejoramiento Animal, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias
Castillo-Juárez H.:
Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana-Xochimilco, Calzada del Hueso 1100, 04960, Distrito Federal, Mexico
Bronze
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