As we enter into bull sale season, now is a good time to review the important factors to consider when selecting a bull. On average, one bull will cover about 25 cows. Therefore, one bull is responsible for one half of the genetic makeup of that entire calf crop.
First it is important to be sure that your bull power matches your herd needs and expectations. Identify what characteristics of a bull are needed. These include considerations about breed marketability, whether breeding to replacement heifers and/or saving replacement heifers, whether marketing at weaning or retaining ownership, environment, available labor, feed resources, and so on.
Once you have identified bull characteristics that are needed for your herd sire, it is important to evaluate potential sires based on both visual (phenotypic) appraisal and EPD (genetic, Expected Progeny Differences) data. Consider the following:
- Physical Soundness – bulls must be physically able to service the cow herd. Therefore, sound feet and legs, clear eyes, non-pendulous sheaths, and general overall condition should be evaluated.
- Genetic Performance – Genetic performance can be evaluated through the use of EPD’s (Expected Progeny Differences). EPD’s predict the difference that can be expected in the performance of progeny of two or more sires of the same breed when mated to animals of the same genetic potential. EPD’s are the best predictors of the genetic performance of an individual animal. EPD’s of importance depend on the production goals of each individual rancher. For example, producers who are marketing calves at weaning will likely focus on growth traits like weaning weights and yearling weights. Producers breeding to replacement heifers might strongly consider birth weight EPD’s or Calving Ease indices. EPD’s of importance truly depend on the goals and production level of each individual ranch.
- Acclimation to the Environment – Choosing a bull that is acclimated to your ranch’s climate and management conditions is also important.
- Other factors to consider – temperament, frame size, scrotal circumference (an indicator of daughter’s age at puberty).
Once a bull has been selected and purchased, it is important to conduct annual breeding soundness exams on your bull battery.