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animal handling facility is suitable.
A compulsory database must be collected for all BBSEs, but, informed by veterinary advice, the client can select additional categories they wish to have included in the evaluation to suit their specific purposes (Figure 7.3). In this context, breed societies can select additional parameters they wish to have evaluated for bulls in their respective stud sales with the knowledge that the outcome of that evaluation will be reflected in the result shown in the respective fertility category.
Figure 7.3 An example of BBSE data collection options provided by BullCheck software as used by veterinarians accredited in the BullCheck accreditation program managed by the ACV.
Source: Used with permission from ACV, Australia.
If owners or veterinarians choose to truncate the evaluation procedure, that is possible. But the certificate clearly shows a potential purchaser the testing procedures that are available and which ones were performed. The bull owner or their agent is required to sign the certificate to affirm that bulls have not undergone procedures to rectify faults that may have otherwise caused them to fail the standards. The veterinarian is required to sign the form to confirm the evaluation was in accordance with ACV standards.
An important feature of this approach is that the veterinarian is not required to make an overall judgment of whether the bull has normal capacity to sire calves under natural mating management. Instead, the veterinarian assesses each category to determine if standards are met and the client receives a report informing them of whether it meets the individual category standards. This report, with adequate room for veterinary comments, allows clients or potential purchasers to make an informed decision on how to proceed with the bull.
With the current software iteration called BullCheck, there is seamless integration with morphology software, which allows the veterinarian to either perform their own morphological assessments or follow the ACV recommendation and export the bull data to a dedicated morphology laboratory that will receive the fixed semen samples and import the results back into the BullCheck program for assimilation into the report. To assist with reducing ambiguity in the process, the back page of the report (Figure 7.4) explains in plain language the symbols used on the report, the limitations of the evaluation, and qualifiers to the interpretations.
Figure 7.4 As with the South African system, Australian BBSE reports have a back‐page description explaining the process, report symbols, and limitations and qualifiers to the process.
Source: From AVA, The South African system, Australian BBSE reports, © Australian Veterinary Association Ltd.
The Australian system differs to that of other regions with the requirement for veterinarians using this system to become accredited with the ACV. The goal of the accreditation system is to ensure consistency in data collection, interpretation, and reporting. While the process requires effort for both ACV administration and veterinarians wishing to become accredited, the primary goal is anecdotally being achieved. An added benefit is that accredited veterinarians may be securing a market advantage as breeders and breed societies realize the advantages of a well‐regulated process. The summary of this system is that veterinarians must demonstrate meeting a threshold of BBSE experience or attend an ACV BBSE training day; they must demonstrate having suitable equipment to perform the procedures, including having a binocular microscope with warm stage, a portable incubator or slide warmer, and a computer loaded with a current version of the BullCheck software; and they must pass an open‐book, online examination. Accredited veterinarians must agree to be in a trace‐back system so that disputes can be investigated, and currently in development is a process for accreditation maintenance.
The ACV also temporarily ran an accreditation program for sperm morphologists. This process initiated the development of standardized procedures and quality assurance programs surrounding morphology assessment and reporting. However, the accreditation program had to be abandoned as the ACV did not have effective regulatory authority over non‐veterinarians performing the work, meaning they could not follow through with proposed trace‐back programs. Currently the ACV provides endorsement for morphologists who have agreed to meet the required laboratory standards.
Canada
In Canada, there have been two systems utilized for BBSE [16]. Some practitioners follow the American SFT guidelines described previously, while the Western Canadian Association of Bovine Practitioners (WCABP) has produced its own guidelines and forms. The WCABP BBSE process is similar to the SFT guidelines except for varied thresholds for SC, morphologically normal sperm, and sperm motility
[16].
In contrast to the SFT system, the WCABP system considers breed and age when setting the SC threshold. In the SFT system, the lower SC threshold is the same (30 cm) for bulls of any Bos taurus breed between 12 and 15 months of age [10]. However, in the 2018 version of the SFT BBSE manual there is recognition of the profound influence of breed and age on SC, providing veterinarians with information to tailor recommendations to clients with different breeds. The WCABP system sets the SC threshold for each breed and age as one standard deviation below the mean [17], which means that 16% of bulls with the smallest SC may be culled. Both systems classify bulls as having either satisfactory or unsatisfactory SC scores, but do not further categorize satisfactory bulls to allow positive selection pressure based on SC.
For sperm motility and sperm morphology, the SFT system categorizes bulls as either satisfactory or unsatisfactory, while the WCABP system adds another category called questionable for bulls whose values are slightly below the set threshold. As a result, in the WCABP system there are four possible overall classifications for bulls, ranging from satisfactory, questionable, decision deferred, or unsatisfactory breeders. The decision deferred classification is used for bulls that are expected to show a substantial improvement in semen quality before the breeding season, thereby warranting a re‐evaluation within several weeks [18].
The UK
The use of BBSE procedures in the UK is a relatively recent development, with the use of formal reporting and certificates commencing in 2009 [19]. Oversight of the standards is provided by the British Cattle Veterinary Association (BCVA) and in general they follow the SFT guidelines, with some influence from the ACV and South African systems. An important distinction with the UK system is that in contrast to other systems that call the process a Breeding Soundness Evaluation, the BCVA considers it more prudent to describe the process as a Pre‐Breeding Examination (PBE) [20]. Removal of the word “soundness” presumably reduces legal liabilities within the UK. Like the South African system described later in this chapter, the UK PBE certificates are provided in carbon‐copy pads with assessment standards detailed on the reverse of the form. The certificates provide options for selecting one of three reasons for performing the examination, either pre‐sale, pre‐breeding, or insurance. The main categories assessed are divided into: Physical examination; Semen examination; and Assessment of mating ability. As with other systems, the bull can receive a classification without the mating ability test being performed. Similar to the South African system, the UK PBE certificate requires the bull to be classified as either Suitable or Unsuitable for Breeding. Within the Suitable for Breeding category,