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Submitted to: Meeting Abstract
Publication Type: Proceedings Publication Acceptance Date: 3/1/2005 Publication Date: 7/1/2005 Citation: Thallman, R.M. 2005. Marker assisted selection and combination EPDS [proceedings]. Proceedings of Texas A&M University Beef Cattle Short Course, College Station, TX, August 2, 2005. 9 pp. Interpretive Summary: The benefits of DNA testing are briefly discussed. The number of DNA tests for quantitative traits in beef cattle has increased rapidly over the past four years. The currently available tests and companies are listed. With the rapid growth of DNA testing in beef cattle, breeders have many decisions to make and little information with which to make them. Independent characterization of DNA tests is a process designed to provide some of that information and is described briefly. The development of Beef Improvement Federation Guidelines for DNA testing is underway to provide other types of information to breeders. Most current tests are for genes primarily related to carcass traits. Research aimed to develop tests for feed efficiency, reproduction, and disease resistance are underway. DNA tests should not be used as all-or-none selection criteria, but rather should be used as one of several sources of information upon which selection is based. The proper allocation of selection pressure to these various sources of information will be easier when DNA test results are incorporated into the national cattle evaluation system. An hypothetical example of DNA-adjusted expected progeny differences is included to illustrate that DNA tests provide the most information when applied to animals that would otherwise have genetic evaluations with low accuracy. Young bulls that are candidates to be used as sires of seedstock are excellent candidates for DNA testing. There are many challenges ahead in the adoption of DNA testing by the beef industry, but it is expected to result in greater genetic progress, especially for traits for which data are limited. Technical Abstract: The benefits of DNA testing are briefly discussed. The number of DNA tests for quantitative traits in beef cattle has increased rapidly over the past four years. The currently available tests and companies are listed. With the rapid growth of DNA testing in beef cattle, breeders have many decisions to make and little information with which to make them. Independent characterization of DNA tests is a process designed to provide some of that information and is described briefly. The development of Beef Improvement Federation Guidelines for DNA testing is underway to provide other types of information to breeders. Most current tests are for genes primarily related to carcass traits. Research aimed to develop tests for feed efficiency, reproduction, and disease resistance are underway. DNA tests should not be used as all-or-none selection criteria, but rather should be used as one of several sources of information upon which selection is based. The proper allocation of selection pressure to these various sources of information will be easier when DNA test results are incorporated into the national cattle evaluation system. An hypothetical example of DNA-adjusted expected progeny differences is included to illustrate that DNA tests provide the most information when applied to animals that would otherwise have genetic evaluations with low accuracy. Young bulls that are candidates to be used as sires of seedstock are excellent candidates for DNA testing. There are many challenges ahead in the adoption of DNA testing by the beef industry, but it is expected to result in greater genetic progress, especially for traits for which data are limited. |
