As the breeding season approaches for spring calving herds, it becomes essential to address the challenges of heat stress in cattle. Producers planning to synchronize and artificially inseminate replacement heifers or adult cows should be mindful of potential issues arising from hot weather conditions.
Traditionally, producers adhered to the AM/PM rule of artificial insemination, waiting 12 hours before breeding a female in heat. However, recent research in dairy cattle has shown that there is no significant advantage to this approach. Pregnancy rates have been comparable between morning-only insemination and following the AM/PM rule. Moreover, new findings from Oklahoma State University raise concerns about handling and inseminating cattle in the evening, given their elevated core body temperatures during that time.
Studies using rumen temperature boluses have revealed that the core body temperature of beef cows reaches its peak 2 to 5 hours after the highest daytime temperature. As the highest temperatures often occur in the late afternoon, cattle experience elevated core body temperatures from 6 PM to 11 PM. This is particularly relevant for producers in the Southern Plains, where heat stress is more prevalent.
To mitigate heat stress during breeding, it is recommended to inseminate all cattle in the morning. This approach eliminates the potential challenges associated with evening breeding. If timed artificial insemination is preferred, scheduling cattle working, especially the insemination process, in the morning hours is advisable.
By considering heat stress and making appropriate adjustments, producers can optimize the success of artificial insemination programs, ensuring the well-being and reproductive performance of their cattle.
Photo Credit: gettyimages-jacqueline-nix
Categories: Ohio, Livestock, Weather