A COMPILATION OF RESEARCH RESULTS INVOLVING TROPICALLY ADAPTED BEEF CATTLE BREEDS S-243 and S-277 Multistate Research Projects Southern Cooperative Series Bulletin 405 http://www.lsuagcenter.com/en/crops_livestock/livestock/beef_cattle/breeding_genetics/trpoical+breeds.htm Contact information: Dr. David G. Morrison, Associate Director Louisiana Agricultural Experiment Station P. O. Box 25055 Baton Rouge, Louisiana 70894-5055 Phone: 225-578-4182 FAX: 225-578-6032 Email: [email protected] ISBN: 1-58161-405-5 State Agricultural Experiment Stations do not discriminate on the basis of race, sex, color, religion, national origin, age, disability, or veteran status in provision of educational opportunities or employment opportunities and benefits. - 1 - Preface The Southern region of the U.S. contains approximately 42% of the nation’s beef cows and nearly 50% of its cow-calf producers. The region’s environment generally can be characterized as subtropical, i.e. hot, humid summers with ample rainfall supporting good forage production. Efficient cow-calf production in the humid South is dependent on heat and parasite tolerance and good forage utilization ability. Brahman and Brahman-derivative breeds generally possess these characteristics and excel in maternal traits. Consequently, they have been used extensively throughout the Southern Region in crossbreeding systems with Bos taurus breeds in order to exploit both breed complementarity and heterosis effects. However, several characteristics of Brahman and Brahman crossbred cattle, such as poor feedlot performance, lower carcass quality including meat tenderness, and poor temperament, whether real or perceived can result in economic discounts of these cattle. Therefore, determining genetic variation for economically important traits among Brahman and Brahman-derivative breeds and identifying tropically adapted breeds of cattle from other countries that may excel in their performance of economically important traits in Southern U.S. environments have been greatly needed. The S-243 and S-277 multistate research projects have focused on these research problem areas and this publication is a compilation of those research results. The 24 scientific papers contained herein emanate from 50 contributing scientists from seven Southern Region states (AR, FL, GA, KY, LA, OK, TX) plus Nebraska. The research was conducted both at land-grant university experiment stations and at USDA-ARS facilities. This bulletin was developed from a day-long tropically adapted breeds symposium held in Little Rock, AR on February 8, 2005, during the annual meeting of the Southern Section of the American Society of Animal Science. The symposium was hosted by the S-1013 multistate project technical committee. Special acknowledgement is expressed to Dr. Larry Cundiff of the U.S. Meat Animal Research Center (USMARC), Clay Center, NE, who spawned the idea for the symposium and served ably as its organizer. Sincere appreciation is also expressed to Ms. Jan Watts at USMARC who converted all 24 papers to Journal of Animal Science style, incorporated peer review changes, and transmitted the entire document to the LSU AgCenter’s Communications Department. Further acknowledgement and thanks are expressed to two LSU AgCenter faculty; Ms. Jane Honeycutt, Publications Editor, for conducting the final bulletin editing and to Dr. Frankie Gould, Director of Public Relations and Communications, for posting it to the institution’s web site. It has been my privilege to work with this productive group of scientists during S-277 and currently with the S-1013 multistate research project. Their dedication to animal breeding and genetics in support of the U.S. cattle industry has been exemplary. It is the collective desire of this group that the reports contained in this bulletin will be useful both to animal scientists and beef cattle producers. In addition, it is quite fitting that this bulletin be dedicated to Dr. Keith Gregory, who contributed so much to the science of animal breeding. David G. Morrison S-1013 Administrative Advisor - 2 - Tropically Adapted Breeds – Regional Project S-1013 Dedication land resource, physical plant, and organization of scientific and support staff have had a great and lasting impact on multidisciplinary research programs at MARC. Dr. Gregory maintained an active personal research program during the time he served as Director at MARC. He conceived, initiated, and provided leadership for a comprehensive Germplasm Evaluation Program to characterize breeds of cattle representing diverse biological types for rate and efficiency of growth, carcass composition, and meat quality, reproduction and maternal performance, cow size, and herd life. Results from the project have affected breeding programs used for beef production in the United States and all major beef-producing areas of the world. After completing his role as Director in 1977, he committed his full time and effort to leadership of two major beef cattle breeding projects. In 1978, he initiated a comprehensive project on Germplasm Utilization in beef cattle. Results from this program demonstrated that significant heterosis was maintained Dr. Keith E. Gregory in composite populations, proportional to the number 1924-2005 of breeds used in foundation of the population. Also, composite populations could be used to optimize Proceedings of this symposium on tropically performance levels and match genetic potential with adapted breeds are dedicated to the memory of Dr. the climatic environment, feed resources, and Keith E. Gregory. Dr. Gregory was born October 27, consumer preferences with greater precision and 1924, in Macon County, NC. During World War II, uniformity than possible with alternative he served in the U.S. Navy. He received his B.S. crossbreeding systems. As a result, a significant degree from North Carolina State University in 1947, number of composite populations have been the M.S. degree from the University of Nebraska in developed by cattle breeders in diverse geographic 1949 where he worked with Dr. Marvel Baker, and the regions of the United States and the world. Ph.D. degree from the University of Missouri in 1951 Dr. Gregory also served as leader of the project, under the direction of Dr. Gordon E. Dickerson. Dr. Twinning in Beef Cattle, from 1981 to 1998. Gregory began his teaching and research career in Twinning frequency has increased significantly in the 1951 as an associate professor at Auburn University. population in response to innovative selection criteria In 1955, he joined the Agricultural Research Service, and an effective breeding program. Today more than U.S. Department of Agriculture, as Investigations 55% of the calvings in the herd are multiple births. Leader for Beef Cattle Breeding Research in the North Dr. Gregory was an author or co-author of more Central Region located at the University of Nebraska, than 200 papers published in refereed scientific Lincoln. In 1957, Dr. Gregory initiated a long-term journal and author of more than 150 other publications crossbreeding project to evaluate heterosis effects on including book chapters, bulletins, and proceedings of major bioeconomic traits at the Fort Robinson Beef national and international scientific or beef industry Cattle Research Station, Crawford, NE. Results of meetings. He has consulted on research and this project had a major impact on the adoption of development programs and presented invited papers to crossbreeding systems to use heterosis in the beef national at international audiences in Uganda, Kenya, cattle industry. Republic of South Africa, Colombia, Brazil, In 1966, Dr. Gregory was appointed as the first Argentina, Chili, Turkey, New Zealand, Republic of Director of the U.S. Meat Animal Research Center, Korea, India, Paraguay, United Kingdom, Spain, ARS, USDA, Clay Center, NE. His vision, focus, and Australia, and Canada. total commitment to development of the 35,000-acre - 3 - Tropically Adapted Breeds – Regional Project S-1013 Table of Contents Thrift, F. A., and T. A. Thrift. Rationale for Evaluating Alternative Sources of Subtropically Adapted Beef Cattle Germplasm. .......................................................................................................................................................6-15 Riley, D. G., G. R. Hansen, J. R. Crockett, T. A. Olson, C. C. Chase, Jr., and D. E. Franke. Florida Crossbreeding Research. .........................................................................................................................................................16-25 Randel, R. D. Reproduction of Bos Indicus Breeds and Crosses. .........................................................................26-39 Rouquette, F. M., Jr., J. J. Cleere, C. R. Long, and R. D. Randel. Birth to Harvest Attributes of Brahman and Brahman-influenced Steers..............................................................................................................................40-59 Buchanan, D., and R. Frahm. Zero, ¼, and ½ Brahman Cows in Spring vs Fall Calving Programs.....................60-63 DeRouen, S. M, W. E. Wyatt, T. D. Bidner, P. E. Humes, D. E. Franke, and D. C. Blouin. Cow-calf Performance of Brahman-British and Brahman-Continental Beef Females.........................................................................64-72 Wyatt, W. E., S. M. DeRouen, T. D. Bidner, P. E. Humes, D. E. Franke, and D. C. Blouin. Feedlot Performance and Carcass Characteristics of Brahman x British and Brahman x Continental