Optimal Genetic Improvement for the High Producing Cow

Abstract

Many 40,000-lb (18,144kg) cows exist in today's dairy population, but herds capable of 40,000-lb averages for all cows remain to be developed. Traditional genetic improvement practices, based on consistent use of current high-ranking AI bulls selected to improve economically important traits, will remain important tools to develop high producing cows. Future breeding strategies will likely include attention to how high production is achieved and may include direct selection for increased appetite or some measure of energy balance to support high production, reproduction, and immune function. Direct selection for improved fertility, perhaps involving traits not presently used in herd management, may prove to be necessary as yields increase. Roles for evolving technologies such as marker-assisted selection, manipulation of the bovine genome, and cloning remain unclear, but will likely be incorporated into traditional progeny testing schemes. Equipment to routinely monitor physiological functions may encourage the establishment of large progeny test herds with expanded data recording capability. The expense could lead to proprietary genetic lines and private genetic evaluation systems such as exist in poultry and swine. Pedigree information will become more important in commercial herds to manage inbreeding. The dairy industry can expect to benefit from current research efforts in human genetics. However, current funding of dairy breeding research in the United States will limit the number of individuals trained in methods to implement those results in dairy cattle.