INTEGRATED STRATEGIES AND METHODOLOGIES FOR THE GENETIC-IMPROVEMENT OF ANIMALS

The current emphasis of biotechnology in animal agriculture stresses the need for identification of major genes affecting growth and development, reproductive performance, lactation, and disease resistance characteristics. Identification of allelic variants of genes that affect quantitative traits, either positively or negatively, may be used to increase genetic potential for production of livestock products. The long-term objectives of our integrated quantitative and molecular approach are to develop precise genomic maps of livestock species and to understand how allelic genes affect quantitative phenotypes. Work is underway to identify new polymorphic genetic markers and to perform linkage analysis of such markers with important economic traits. The relevance of this research is specifically to permit an accelerated rate of genetic improvement via marker-assisted selection, selecting animals based upon their genotype in addition to using phenotypic data. Other important ramifications of this endeavor include the identification of genes that may have commercial application through construction of transgenic animals and the development of methods and reagents to further gene mapping in livestock species. This paper outlines the nature of the collaborative approach to animal breeding research developed by animal scientists at the University of Illinois and discusses strategies for integrating traditional molecular and quantitative genetics disciplines. © 1990, American Dairy Science Association. All rights reserved.