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of mating ability was performed or whether the classification was based solely on the physical and semen evaluations. While there is no opportunity to place bulls in a “questionable” or “deferred” category, the system encourages the use of the comments section to provide further information and prognoses for bulls not meeting the standards.
The Netherlands
In the Netherlands, BBSE procedures closely follow those described by the SFT [21]. The reason for mentioning the BBSE procedures used in this region is to highlight the emphasis placed on consistently diluting semen in order to gain an accurate individual motility assessment. Bulls can fail a BBSE based on a poor individual motility assessment, and poor semen handling or an inability to clearly visualize individual sperm can adversely affect the result. In the Netherlands, a routine 1 : 80 dilution of semen with physiological saline warmed to 37 °C prior to individual motility assessment is described. In the absence of direct concentration estimates, such a process will result in diluted concentrations of 2.5 × 106 to 13 × 106 cells/ml in the assessment sample. Concentrations such as this allow clear visualization of individual spermatozoa. This process is relatively easily performed in the field by adding 790 μl of warmed saline or PBS to 10 μl of semen.
South Africa
The Livestock Health and Production Group of the South African Veterinary Association took the initiative to standardize BBSE within South Africa [22]. As was the case in other regions, this group recognized that advances in knowledge in BBSE had led to variation in what services were being offered by veterinarians. Such variation was identified as a source of dissatisfaction to clients and practitioners, with both groups experiencing inconsistency in the costs and outcomes of bull examinations [22]. This group proceeded to produce a paper‐based recording and reporting system for BBSE utilizing evidence‐based standards for the selected parameters.
In this system, the veterinarian, in consultation with the client, has the option of selecting the purpose of the examination as either:
1 A natural service sire for sale or owner use
2 A donor of semen for sale
3 An examination for insurance purposes.
There are compulsory aspects of the testing, which include:
1 A general clinical examination
2 Physical examination of the genital system
3 Semen collection and evaluation
Other procedures such as disease testing are optional and depend on conversations between the veterinarian, the client, or the insurance company.
The certificate record (Figure 7.5) provides a list of the recommended examinations and tests for the bull. The veterinarian is required to circle on the certificate which testing was performed and to circle the purpose for which it was performed as noted in items A, B, or C above. Certificates are available in book form, with a carbon copy, which remains in the book. The reverse of the form (Figure 7.6) provides the standards for each parameter and explanatory notes, similar to the Australian system.
Figure 7.5 The standard veterinary BBSE certificate used in South Africa.
Figure 7.6 Explanatory notes accompanying the South African BBSE certificate.
A unique aspect of the South African system is that certificates are only issued if the bull meets the BBSE standards and is classified as breeding sound. Other than the provision of space for some qualifying comments, there is no facility on the certificate to classify the bull any other way. Therefore bulls are effectively classified as suitable or unsuitable for breeding. Accordingly, the first component of the certificate is a declaration by the veterinarian that the bull complies with the minimum standards set for BBSE examinations for the selected purpose.
Another unique aspect of this system is that no actual parameters are indicated on the document. The reasoning for this is that the evaluation is designed to provide a yes/no answer to whether the bull is “Breeding Sound” at the time of evaluation. The system acknowledges the risk of artifact affecting the result for many of the parameters when different veterinarians assess bulls in varied field situations. Removing quantitative data from the form is seen as a method of removing inappropriate comparisons between bulls. Therefore if a bull meets or exceeds the parameter standards, the actual number is considered irrelevant. This paradigm contrasts with other systems that aim to both answer the “Breeding Sound” question and provide quantitative data in a way that might assist with genetic selection for improved fertility.
While there is no suggestion of an accreditation process for South African veterinarians to utilize the certificates, there is inference that undergraduate training and routine continuing professional education are adequate to maintain the integrity of the system.
BBSE – How the Categories Compare Internationally
The General Physical Examination
All BBSE standards recommend performing a general physical examination as a compulsory part of the process. There is minor variation regarding the scope of the examination, but in general it consists of an overall visual inspection for abnormalities and conformation, assessment of body condition score, examination of eyes, bite, legs/hooves, and gait assessment. In most systems, there is a general implication that the process be streamlined for efficiency. However, the UK system specifically requires auscultation of the heart and thorax in order to complete the BCVA certificate. If abnormalities are detected, all systems provide for a more detailed physical examination either by using written comments or by selecting further options within the available software. Yet, in all systems, there was either minimal guidance or ambiguity surrounding the decision‐making process when conformational and possibly heritable abnormalities were detected. For example, conditions that can have varied degrees of severity such as interdigital fibromas, joint effusion in the hocks, sickle hocks, post‐leggedness, and scissor‐claw were all mentioned as possible reasons for bulls failing the evaluation. To guide clinicians in these instances, the UK and South African systems provide brief instruction on the back of the certificates, but leave the assessment of severity and final classification to be based on the clinical judgment of the attending veterinarian. Similarly, while the SFT manual provides detailed descriptions of many of the abnormalities that will be encountered, clear guidance on when to pass or fail the bull is lacking. For many of the conditions, the Australian system provides descriptions and, in some instances, scoring templates to assist classification. Yet, commonly the advice simply states that “severe” cases should not pass, leaving it up to the veterinarian to determine what is severe and what is acceptable. This situation may result in enough variation in the results to adversely affect the integrity of the process in the eyes of some producers.
In reviewing the processes of the general physical examination and the possibilities for variation in interpretation of the information both within and between systems, the question is raised of whether it is the role of the BBSE process to fail a bull based on the possibility it may have a defect that may affect it at some stage in the future. It may be prudent to cull such a bull if it is to sire seed‐stock, but not so relevant for a bull entering a commercial herd. Consequently, there is a need for all parties to be clear on why the evaluation is being performed, and also to have the option to