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The pre‐breeding period begins 60–90 days prior to the start of the breeding season. Breeding soundness evaluations, vaccinations, and diagnostic testing for reproductive pathogens should all occur at the beginning of this period. Performing these procedures early gives the producer time to find replacements if necessary. Vaccination prior to the start of the breeding season should provide protection to the bull while reducing or eliminating his significance as a disease reservoir or vector. Vaccinating bulls at least 60 days prior to the breeding season should allow any viral shedding or transient negative effects on spermatogenesis to subside before breeding. Body condition can also be assessed at this time and minor adjustments to the diet made if necessary.