By Alexis DeCorby, BSc, PAg, Livestock and Feed Extension Specialist, Yorkton
April 2024
With calving season drawing to a close for many producers, it means it’s time to shift gears and think about breeding season. An unsuccessful breeding season can be costly, resulting in fewer calves or lighter calves to sell next fall. To maximize success this spring and summer, start by following the three Bs of breeding season:
Source: Alexis DeCorby
Body Condition Score
Body condition score (BCS) is an important factor in a successful breeding season. Cows that are not in good body condition will take longer to cycle, resulting in fewer opportunities for successful conception. To maximize first service conception rates, cows need to be on an increasing plane of nutrition prior to and at the time of breeding.
A cow’s nutritional requirements peak around day 60 of lactation, with most cows returning to estrus at approximately 45 days post calving. Milk production and rebreeding require more energy than standard maintenance. Providing supplemental energy, often grain, post calving is one of the easiest ways to set your cow herd up for reproductive success. For the best results, aim to have cows at a minimum 2.5 BCS. Cattle that go out to pasture below a Canadian 2.5 BCS take longer to rebreed, resulting in an extended calving season the following year, and lighter calves to sell at weaning.
Breeding Soundness
While cow condition plays an important factor in a successful breeding season, it is also important to remember that your bulls need to be fit to breed. It is just as important to provide your bulls with adequate nutrition to maintain their condition prior to turn out. A breeding soundness exam predicts the potential fertility of a herd sire for that breeding season. Breeding soundness exams include a physical soundness evaluation, evaluation of testicular size and semen quality. To ensure your herd sires are ready for breeding season, consider a breeding soundness exam 30 to 60 days before turnout. This gives you adequate time to source a replacement bull, or retest your herd sire, if needed. Remember, bull breeding soundness doesn’t stop at pasture turnout. Monitoring bulls for ailments or injury during breeding season ensures that you will be able to correct any issues in a timely manner.
(pre) Breeding Vaccines
Pre-breeding vaccinations are an often-overlooked component of a successful breeding season. There are several diseases that impact reproduction, making it difficult or impossible for a cow to carry a calf to term. Two common culprits are Bovine Viral Diarrhea and Infectious Bovine Rhinotracheitis. Both viruses have the potential to cause abortions. Bovine Viral Diarrhea may also lead to persistently infected calves that will shed the disease throughout their lifetime, infecting their pen mates and cattle within fence line contact.
Several bacteria also cause abortion; two prominent examples are Leptospirosis, and Campylobacter, also known as Vibrio. Cows typically recover from a Vibrio infection but are often unable to become pregnant or become pregnant late if the infection occurs during the breeding season. Fortunately, there are vaccines available for these and other important reproductive diseases. It is important to remember that some of these vaccines need to be given at certain intervals before breeding season starts. For more information about pre-breeding vaccine programs, consult your veterinarian.
A successful breeding season requires good management practices before the cows go to pasture. For more information about managing to maximize reproductive success, or other livestock related topics, contact your local livestock and feed extension specialist or the Agriculture Knowledge Centre at 1-866-457-2377.