Ovsynch protocols and timed AI can eliminate the need for heat detection. In today’s beef and dairy economies, improving reproductive efficiency represents one of the best opportunities for boosting profits. A variety of new technologies and, in some cases, existing but under-utilized technologies offer potential for driving those improvements. Naturally, though, they sometimes come with tradeoffs or caveats.
Protocols for artificial insemination (AI), for example, continue to evolve and become more specific to beef versus dairy operations and heifers versus mature cows.
George Seidel, PhD, says progressive beef operations and veterinarians increasingly are moving away from synchronizing estrus toward synchronizing ovulation for timed AI. These ovsynch programs involve timed injections followed by breeding without heat detection. Seidel, who is a distinguished professor at Colorado State University’s College of Veterinary Medicine, also operates a ranch, Rabbit Creek Angus near Livermore, Colo. He has tested ovsynch protocols in his own herd and helped introduce the system to the beef sector. A number of ovsynch protocols are available, and Seidel notes the recommended protocols for heifers differ from those for lactating cows.
At Colorado State University, George Seidel conducts research on sexed semen and synchronization protocols for dairy and beef cattle. University of Missouri animal scientist Dave Patterson, PhD, says timed AI is just one existing technology the beef industry has been slow to adopt. He references Missouri’s Show-Me-Select heifer program as an illustration of trends in beef reproduction. Veterinarians, he says, play a key role in the program.
Show-Me-Select includes a uniform health program geared toward long-term reproductive efficiency. An exam four to six weeks before breeding includes a reproductive tract scoring (RTS) system and a determination of the percentage of heifers cycling.
The scoring system provides a 1 to 5 rating, with 1 representing an infantile reproductive tract and 4 to 5 representing a heifer that has reached puberty and is cycling. Patterson recommends initiating a progestin-based protocol (MGA or CIDR) to synchronize estrus in heifers when 50 percent of the heifers in a group score 4 or 5. Veterinarians also obtain pelvic measurements at the time the pre-breeding exams are performed. Pelvic exams are used as a screening tool for heifers enrolled in the program and are highly correlated to RTS. The combination of service-sire requirements for birthweight or calving-ease-direct EPD and pelvic measurements have dramatically reduced both the incidence and severity of calving problems for heifers enrolled in the program.