Think synchronized breeding isn’t for your cattle herd? Think again.

As a beef producer, your goal is probably just that: to produce pounds of beef. And while raising your herd using a tool like heat synchronization isn’t for everyone, reaping its benefits may be easier than you think.

Synchronizing estrus involves administering a combination of different drugs to alter the estrus cycles of females so that they can be bred at around the same time.

“Synchronizing estrus can bring huge benefits to the bottom line of many beef producers, especially commercial operations,” said Dan Cummings, DVM, Boehringer Ingelheim. “First and foremost, it can help breed more cows earlier in the calving season. The result is older, bigger calves at weaning and a more uniform and consistent calf crop. Uniform groups are not only easier to feed and manage, they are also more attractive to buyers. »

Some studies have shown up to 10 to 17 days of calf age advantage and 20 to 44 pounds more per calf at weaning in programs using estrus synchronization.1

More pounds, less work

In addition to producing more pounds of beef from a more even crop of calves, synchronizing estrus can shorten the calving season, concentrating the time you need to observe them and giving you more time to other projects on your farm. If you keep replacement heifers, they will also likely be more uniform, hit puberty at the same time, and be ready to breed whenever you want.

“Inadequate facilities, time constraints and labor shortages are often the biggest deterrents beef producers see when considering synchronizing their beef herd,” Dr. Cummings explained. “Programs involving artificial insemination or embryo transfer offer the greatest genetic advancement for a herd, but they can also involve four or even five passes in the fall. The key is to work with your veterinarian and choose an approach that’s right for your operation.

Natural serving may be the choice for you

Synchronizing estrus with your bull farm can provide many benefits without the intense management and labor required for artificial insemination (AI) or embryo transfer (ET) programs. Synchronizing with natural service gives you a chance to gain experience with practice and can be a first step to implementing a comprehensive estrus synchronization and AI program.

“A synchronization program using the natural service can be as simple as giving a prostaglandin injection to cows. The bulls come out the day the prostaglandin is administered or five days after the drug is administered,” Dr. Cummings said.

But raising more cows at the start of the breeding season requires more than estrus synchronization, whether you choose natural breeding or AI. Dr. Cummings outlines these steps on the road to success for all programs:

The keys to breeding success

  • Work with your local veterinarian. In addition to being a resource for all of your herd’s health needs, your veterinarian can help structure your breeding program, including products, timing, and estrus timing protocols. Additionally, the purchase and use of reproductive hormones such as prostaglandin requires a veterinary client-patient relationship.
  • Assess facilities and equipment. For reasons of safety and ease of handling, it is important to have a solid alley through which the cattle move easily and quietly, as well as a chute which restrains the cattle for the administration of injections. In AI and ET programs, a strong, well-functioning rearing chute or box is also very important for restraining animals, as well as for the safety and convenience of the technician.
  • Make sure animals are on a good nutrition and cycle plan. Work to ensure cows receive adequate nutrition before and during the breeding season, including an appropriate mineral program. Cows must have a body condition score of 5; first calf heifers 5.5 to 6 years old and yearling heifers 5 to 6 years old.
  • Administer all vaccinations before breeding. Just as you would before any breeding season, all pre-breeding vaccinations should be given according to label instructions – usually 45-60 days before breeding.
  • Prepare the bulls for the breeding season. Cows will not conceive without the service of a healthy, fertile bull. Make sure all bulls pass a comprehensive breeding exam. Administer annual vaccines according to label directions well in advance of participation. When combining estrus synchronization with natural mating, use 2-4 year old bulls as well as agile, active and known sires. A bull-to-female ratio of 1:15 to 1:25 is generally recommended. Make sure the bulls run together before the show so their pecking order is established and they can focus on tending the cows rather than fighting.
  • Minimize animal stress. Heat, cold, and rough or excessive handling are all stressors that can have an extremely negative impact on any breeding program. Be sure to handle animals quietly and calmly. Minimize the impact of environmental stressors as much as possible, providing water and shade in the summer and bedding and windbreaks in the cold months.
  • Keep good records. Building on success and making improvements to any program is nearly impossible without detailed year-to-year records. Be sure to keep track of protocols followed, products used, and results. Comparing individual calving dates and weaning weights from year to year can be helpful in determining if your program is progressing or needs adjustment.

©2022 Boehringer Ingelheim Animal Health USA Inc., Duluth, Georgia. All rights reserved. US-BOV-0415-2022-A

1 Johnson S and Chenoweth P. Use of natural service bulls with synchronized estrus. K-State Search and Extension, Colby, KS. 2020. Available on: Accessed June 30, 2022.