QTL for feed intake and associated traits

Abstract

In typical beef cattle production systems, the breeding herd accounts for 65-85% of the total feed requirements (Ferrell and Jenkins, 1984 ; Montaldo-Bermudez et al., 1990) and 65-75% of this is used for maintenance. Primarily, the very large maintenance requirement is because cattle are a large, slowly maturing species with a low annual reproductive rate. Furthermore, only a single product is harvested (meat). Any improvement in the efficiency with which breeding cows maintain body weight, will result in an increase in total meat production for a given amount of feed. The key to selection for increased efficiency is to be able to accurately measure feed intake, a trait that is both difficult and expensive to measure. A less expensive alternative would be to use a DNA test for markers of genes affecting intake. This approach has the potential to significantly reduce the generation interval. The aim of this project is to locate regions (quantitative trait loci, QTL) in the cattle genome that contain genes affecting intake.