Practical Crossbreeding Programs for Beef Cattle in Florida

Introduction While there are many types of crossbreeding systems possible, the ones most likely to be useful and practical for use in Florida are some form of a rotational crossbreeding system or, in small herds and a few specialized systems, a terminal crossbreeding program. A third option, the rota-terminal, combines both systems and could also be considered for more intensively managed operations. I am able to recommend certain crossbreeding programs over others in part because of the years of research that were conducted on crossbreeding systems here at the Range Cattle REC by F. M. "Mac" Peacock.. One of the purposes of crossbreeding is to utilize the phenomenon of heterosis, or hybrid vigor. Heterosis is measured by the improvement that we get for many traits, particularly those of greatest economic importance to the cattleman, when we cross various breeds. Heterosis generally results in an improvement in cow fertility, calf newborn vigor and survival rate, milk production and calf growth rate. Crossbreeding does not, however, generally have much of an impact on carcass traits, like ribeye area, fat thickness, marbling, etc. The impact of heterosis on the traits that it does increase, however, is so great that the use of purebreds as commercial animals, even in other parts of the country, usually is not economically feasible. Crossbreeding offers another advantage besides heterosis; producers can select breeds whose superior traits will complement each other in a particular crossbreeding system, producing crossbred animals with a more desirable combination of traits than can be found in existing breeds. The effect of combining desirable traits from two or more different breeds to produce superior crossbred animals is referred to as "complementarity." Breed complementarity can be illustrated in terms of adaptation to the Florida climate. Angus cattle are at a disadvantage in Florida during summer months due to their inability to control body temperature during periods of heat stress. Brahman cattle, on the other hand, are comfortable during the summer because they are well-adapted to high temperatures; but they often suffer in the winter during wet, cold, and windy periods. The F 1 animal that results from crossing Angus and Brahman breeds is comfortable during both summer and winter months in Florida; its level of adaptation to cold, and to heat, is intermediate to the corresponding levels of adaptation exhibited by each parental breed. Through proper selection of breeds for use in a crossbreeding system, cattle …