Technical Abstract: The amount of information currently available about the genomes of many livestock species, especially cattle and pigs, has dramatically increased in the last few years and the rate of its accumulation will continue to increase. A large number of useful scientific "tools" are currently available to use in research aimed at understanding biological processes important to livestock production. These resources are being used to understand the biological processes regulating reproduction, body composition and immune function in all livestock species. This research will create many opportunities to use these tools for improvement of livestock production. The best commercial application of these tools is in conjunction with reproductive enhancing technologies such as artificial insemination, embryo transfer and cloning.