Improving Biological and Economic Aspects of Production Efficiency through Genetic Selection and Genome-Guided Replacement Management

Abstract Text:

Improving feed efficiency in dairy cattle is a costly and complex challenge, due to the difficulty in measuring individual animal feed intakes and the need to consider energy demands for growth, lactation, maintenance, health, and fertility. Research projects are underway in several countries to provide genomic breeding values for dry matter intake or residual feed intake of dairy bulls based on genotypes and phenotypes of reference animals in experimental herds. Heritability estimates suggest that direct selection for biological efficiency of feed utilization could lead to significant progress, and this is important because future gains in efficiency due to indirect selection for improved milk yield will be modest. Estimated genetic correlations suggest that residual feed intake is largely independent of the production and type traits currently considered in dairy cattle selection programs, but relationships with health and fertility traits must also be considered.

Keywords:

dairy cattle

genomics

feed efficiency