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The overarching goal for a bull breeding soundness evaluation (BBSE) is to provide a standardized, unambiguous report on the suitability of a bull to be used in a breeding program. A secondary goal may be to utilize the data to facilitate genetic selection for fertility traits. The evaluation process needs to be repeatable, reproducible, efficient, and safe for both the bull and the clinician. There also needs to be flexibility in the process to accommodate differing managerial requirements. Within each managerial situation there needs to be consistency in the process of data collection, data interpretation, and classification of the evaluation outcomes, with results readily understood by the end user. Such consistency helps to maintain the credibility of the BBSE, assisting veterinarians, cattle producers, and researchers alike.

Foundations for the knowledge that underpins the current practices used in the assessment of bull fertility are attributed to research performed in the first four decades of the twentieth century [1]. Seminal research into specific aspects of bull fertility arose out of the USA [2, 3] and Sweden [4]. Following the understanding that many individual factors affect bull fertility, there was a progressive realization of the need to assimilate this knowledge to enable the development and application of minimum standards for each fertility parameter. The assimilation of fertility parameters into a bull fertility evaluation process formed the foundation of BBSE procedures. The earliest documentation in western literature of standardized procedures, interpretation, and reporting for BBSEs was described in 1954 by a group called the Rocky Mountain Society for the Study of Breeding Soundness of Bulls. Following several iterations, this group evolved in 1974 into the American Society for Theriogenology (SFT), with the basis for current protocols, data recording, and reporting being developed [5].

Following on from these initial developments, BBSEs are now conducted by veterinarians throughout the world to estimate the potential for a bull to sire calves under a range of management conditions. These conditions vary from the assessment of bulls pre‐sale for seed‐stock producers; commercial producers using natural mating in multi‐sire or single‐sire situations; assessment for the ability to collect and process frozen semen; and assessment for insurance purposes. These varied contexts coupled with differing production goals mean that the processes for determining and reporting the suitability of a bull for breeding have evolved with a degree of autonomy in different regions. While there are many similarities, there are also variations in the techniques employed, interpretation of the findings, reporting of results, and systems for oversight of the processes within the veterinary profession.