Synchronizing Estrous in Beef Cattle

Synchronization of estrus contributes to optimizing the use of time, labor, and financial resources by shortening the calving season, in addition to increasing the uniformity of the calf crop. The major limitation of estrus-synchronization programs is their inability to induce a potentially fertile estrus and ovulation in noncycling cattle (i.e., prepubertal heifers and anestrous suckling cattle). Because initial estrus-synchronization programs were not designed for successful treatment of noncycling cattle, their use in cow-calf operations generally has not produced results that would encourage greater A.I. use in beef cattle. Currently, less than 7% of beef cows and an estimated 8 to 10% of beef heifers are A.I.-bred in the U.S. The potential for increasing A.I. in beef cattle is great if a system can resolve successfully the problem of the noncycling female at the beginning of the breeding season.