Escudo de la República de Colombia
Sistema Nacional de Biliotecas - Repositorio Institucional Universidad Nacional de Colombia Biblioteca Digital - Repositorio Institucional UN Sistema Nacional de Bibliotecas UN

Application of an autoregressive process to estimate genetic parameters and breeding values for daily milk yield in a tropical herd of lucerna cattle and in united states holstein herds

Carvalheira, J.G.V. and Blake, R. W. and Pollak, E. J. and Quaas, R. L. and Durán Castro, Carlos Vicente (1998) Application of an autoregressive process to estimate genetic parameters and breeding values for daily milk yield in a tropical herd of lucerna cattle and in united states holstein herds. Journal of Dairy Science, 81 (10). pp. 2739-2751. ISSN 0022-0302

Texto completo

[img]
Vista previa
PDF
Available under License Creative Commons Attribution Non-commercial No Derivatives.

127kB

URL oficial: http://www.programaharton.com

Url relacionadas:

Resumen

The objectives of this study were to estimate from test day records the genetic and environmental (co)variance components, correlations, and breeding values to increase genetic gain in milk yield of Lucerna and US Holstein cattle. The effects of repeated observations (within cow) were explained by firstorder autoregressive processes within and across lactations using an animal model. Estimates of variance components and correlation coefficients between test days were obtained using derivative-free REML methodology. The autoregressive structure significantly reduced the model error component by disentangling the short-term environmental effects. The additional information and the more heterogeneous environmental variances between lactations in the multiple-lactation test day model than in the first lactation model provided substantially larger estimates of additive genetic variance (0.62 kg2 for Lucerna; 14.73 kg2 for Holstein), heritability (0.13 for Lucerna; 0.42 for Holstein), and individual genetic merit. Rank correlations of breeding values from multiple lactations and from first lactations ranged from 0.18 to 0.37 for females and from 0.73 to 0.89 for males, respectively. Consequently, more selection errors and less genetic gain would be expected from selection decisions based on an analysis of first lactation only, and greater accuracy would be achieved from multiple lactations. Results indicated that substantial genetic gain was possible for milk yield in the Lucerna herd (34 kg/yr). Estimates of genetic variance for Holsteins were larger than previously reported, which portends more rapid genetic progress in US herds also; under our assumptions, increases would be from 173 to 197 kg/yr

Tipo de documento:Artículo - Article
Palabras clave:Ganado; Livestock; Producción lechera; Milk production; Herencia genética; Genetic inheritance; Correlación genética; Genetic correlation; Zona tropical; Tropical zones.
Temática:5 Ciencias naturales y matemáticas / Science
5 Ciencias naturales y matemáticas / Science > 59 Animales / Animals
Unidad administrativa:Sede Palmira > Facultad de Ciencias Agropecuarias > Departamento de Ciencia Animal > Zootecnia
Código ID:5079
Enviado por : Profesor Rómulo Campos Gaona
Enviado el día :15 Noviembre 2011 19:15
Ultima modificación:11 Oct 2012 20:16
Ultima modificación:11 Oct 2012 20:16
Exportar:Clic aquí
Estadísticas:Clic aquí
Compartir:

Solamente administradores del repositorio: página de control del ítem

Vicerrectoría de Investigación: Número uno en investigación
Indexado por:
Indexado por Scholar Google WorldCat DRIVER Registry of Open Access Repositories OpenDOAR Metabiblioteca BDCOL OAIster Red de repositorios latinoamericanos DSpace BASE Open archives La referencia Colombiae Open Access Theses and Dissertations Tesis latinoamericanas CLACSO
Este sitio web se ve mejor en Firefox