Animal Science Department


Date of this Version



Presented at Range Beef Cow Symposium XXII, November 29, 30, and December 1, 2011, Mitchell, Nebraska. Sponsored by Cooperative Extension Services and the Animal Science Departments of the University of Wyoming, Colorado State University, South Dakota State University, and the University of Nebraska–Lincoln.


Prior to the mid 20th century, reproductive management of both beef and dairy cattle consisted primarily of purchasing a bull every 2 years from a neighbor thought to have a herd with above average genetics. That description is still embarrassingly close to the truth for the majority of beef cattle herds in North America. The one striking difference is that bulls being purchased currently are, in fact, usually above average genetically. One result is that the amount and quality of beef produced per cow or per unit input of feed, labor, etc. have increased dramatically, at least partly due to continual genetic change.

Why bother with superimposing reproductive technology on management of cattle? At least in some situations, the following can be accomplished more efficiently or rapidly with aid of reproductive technology:

  • The first priority is simply to get the cow or heifer pregnant as close to the optimal time as possible. For most herds, non-pregnant and late pregnant cows are the most costly problem in the operation.
  • A second priority is genetic improvement to meet goals of the herd, e.g. profitability.
  • A third set of priorities, especially relevant as larger numbers of cattle are managed per person, include convenience/efficiency objectives such as shortening the calving season, introducing the polled trait, decreasing dystocia, especially in heifers, etc. Note that many of these also have animal welfare benefits.
  • Experimenting with new approaches. This can be a low or high priority. Trying new things can maintain interest of high value employees and the younger generation. This also can rejuvenate oldsters!