Manage Bulls Between Breeding Seasons

OMAHA (DTN) -- While the breeding season might be over for some cow-calf producers, the bulls still need some attention. Rest and proper nutrition are essential for helping bulls recover from the breeding season.

Extension specialists recommend a comprehensive approach to bull management. This would include targeted nutritional supplementation, a soundness exam before the next breeding season and managing their workload.

BULLS LOSE WEIGHT

Kansas State University Extension Veterinarian Todd Gunderson said bulls need some time to recover after the breeding season. See that here: https://www.ksre.k-state.edu/…. In addition, they also need to prepare for the next breeding cycle.

"A bull may lose anywhere from 100-200 pounds of bodyweight during a breeding season," Gunderson said. "He's going to need at least a couple of months to recover body condition and complete spermatogenesis (a process of sperm cell development)."

Phillip Lancaster, a Kansas State University Extension beef cattle nutritionist, said typically bulls are in a body condition score of 6 when they are turned out with the cows for breeding season. After the season, it is likely they will drop to a score of 5 and producers need to plan supplement strategies based on their forage resources.

Whether they are grazing on warm- or cool-season grasses, bulls will require strategic nutritional support, he said. This will ensure optimal fertility and performance in future breeding seasons.

Lancaster said each operation has different forage resources and regional conditions, but it is important to care for bulls even when they are not covering cows.

BULLS NEED PROPER DIETS

Bulls should gain weight at a moderate rate unlike a feedlot steer, according to a post from Penn State University Extension. See that here: https://extension.psu.edu/…. Nutrition will depend not only on the body condition score but also on the animal's age.

For bulls under the age of two, a proper diet should support both growth and maintenance. Protein and energy levels in the diet must be adjusted to support both growth and reproductive health.

"Work with a nutritionist to assess if the diet meets the animals' needs," the report said.

Producers with more than one bull should make sure the bulls have appropriate spacing in holding pens and at the bunks. Separating bulls by age and diet requirement will optimize growth and maintenance by allowing bulls access to the diets that will best suit them, according to the Penn State report.

CONDUCT BREEDING SOUNDNESS EXAMS

Cow-calf producers should conduct a breeding soundness exam on each bull prior to the breeding season, according to a report from the Noble Research Institute. See that here: https://www.noble.org/….

Veterinarians typically suggest 60 days in advance of turnout for a soundness exam in case the bull fails the first test. A retest should occur 30 days after the first test.

If a bull fails the retest, a producer would still have time to find a replacement bull.

"You will need time to find a suitable replacement that meets the goals of your operation rather than just finding a fertile bull," the report stated. "The closer to turnout date it gets, the less quantity and quality bulls of service age are available and the cost typically goes up for these bulls."

The Noble report also suggested producers develop an effective herd health program for bulls.

All bulls should receive regular vaccines as well as breeding disease vaccines such as leptospirosis and vibriosis. Vaccines against internal and external parasites will increase the health status of bulls, the report said.

Do not overwork bulls, especially younger ones.

"Cow-to-bull ratios need to be evaluated based on pasture size and terrain, age of bull, and whether or not an estrous synchronization program will be used," the Noble report stated. "Young bulls should not be overworked because there is a higher probability of injury or a reduction in body condition great enough that negatively impacts sperm quality."

Bull health is important and cow-calf producers should be paying attention to this aspect throughout the year, the report added.

Russ Quinn can be reached at Russ.Quinn@dtn.com

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