Genetic, phenotypic and environmental trends in two populations of pig

• Carmen Rico ^[1] ; M. Menchaca ^[1]
  1. [1] Instituto de Ciencia Animal, La Habana
• Localización: Archivos Latinoamericanos de Producción Animal, ISSN 1022-1301, ISSN-e 1022-1301, Vol. 1, Nº. 1, 1993
• Idioma: inglés
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• Resumen

  • Data from the field performance test of 10495 Yorkshire females and 6106 Hampshire pigs of both sexes that were on trial from 1979 to 1985 and from 1980 to 1987, respectively, were analyzed to estímate the genetic, phenotypic and environmental trends using the covariance matrix of the yearly constants. In the Hampshire population, the annual genetic trend for average daily gain (ADG), weight for age (WA) and backfat thickness (BF) were significant with valúes of 2.7 g, 2.3 g and 0.43 mm, respectively. The estimates for the Yorkshire population were 2.7 g and 1.7 g for ADG and WA and the BF estímate was not significant. The environmental conditions during the period of study with the Hampshire population were very unfavorable, resulting in an also unfavorable phenotypic trend. It was concluded that the low rate of gatn and the environmental variability could account for the genetic gain being lower than 1 % for rate of growth.