Department of Animal Science
Date of this Version
12-5-1995
Abstract
Composite bulls won't perform magic or offset poor management but they offer a tool to help solve production/management problems and optimize production for a wide range of environments.
The impact of crossbreeding through heterosis (hybrid vigor) and utilization of breed differences (complementarity) for major traits like reproduction, calf survival, maternal ability, growth, longevity and other fitness traits is powerful. The cumulative effect of crossbreeding can increase calf weight weaned per cow exposed by 20 percent.
Conventional crossbreeding programs fall short in "management ease" because: 1) Rotations tie up several breeding pastures; thus, complicating grazing management, 2) Identification by sire breed type is required for proper breeding pasture assignment and 3) There is a continual struggle with swings in breed composition as long as straight bred sires are used; thus, complicating heifer selection and marketing of steer progeny.
Crossbreeding, along with selection against extremes, offers a method to blend desirable characteristics of several breeds in an effort to use both heterosis and complementarity while avoiding unfavorable genetic antagonisms. Composites may be the preferred tool to implement such a crossbreeding/balanced trait selection program.
Comments
Published for Proceedings, The Range Beef Cow Symposium XIV December 5, 6 and 7, 1995, Gering, Nebraska.