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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 vary the examination so it is relevant to the managerial context.
The Reproductive Physical Examination
All BBSE standards recommend performing a physical reproductive examination. There is general agreement across the regions that it should involve the following:
1 Transrectal palpation of the accessory sex glands, with emphasis on assessing the vesicular glands.
2 Examination of the sheath, with some standards providing the non‐compulsory option of assigning a sheath score.
3 Palpation or ideally visualization of the penis.
4 Palpation of the scrotum and assessment of the scrotal cleft.
5 Palpation of the testes, epididymides, and scrotal cords.
6 Measurement of SC.
Transrectal palpation of the accessory sex glands is a compulsory part of the BBSE in all regions evaluated. While all structures are evaluated, the clear emphasis is on assessing the vesicular glands, as they most commonly have pathology and their condition is considered to reflect pathology that may be present in other parts of the tubular tract. None of the standards provided clear guidelines on what level of pathology of the seminal vesicles would result in the requirement for reassessment or a fail. The general implication from all regions was that the presence of any of the following would mean the bull would not meet the requirements for the reproductive physical examination: palpable, acute infection; a high concentration of neutrophils in the semen; or enlarged seminal vesicles in conjunction with sperm morphology defects consistent with inflammatory changes to the tubular tract. One area that was not clear in some of the guidelines was what was meant by a “high concentration of neutrophils.”
Evaluation of the sheath is recognized as a compulsory part of a BBSE and bull selection in all regions except the BCVA [1022–26]. In most regions, failure of the bull in this aspect is based on the veterinarian's opinion of the presence of pathology. In the ACV and SFT systems, a non‐compulsory scoring system is utilized to assist veterinarians with pass/fail and genetic selection decisions, but the provision of a sheath score is not considered an essential aspect of the BBSE in any region. The ACV sheath‐scoring system has developed over the past 20 years, with current recommendations providing a score on a scale of one to five. Where a score of one represents a small sheath and five represents a large pendulous sheath [23]. There is a plan to upgrade the ACV scoring system [27], but there is still conjecture regarding the relevance of including factors in the scoring system such as the presence of preputial eversion.
There was no variation in the regional recommendations for the assessment and interpretation of penile defects. All standards recommended visualization of the penis during the assessment. Visualization was ideally at electroejaculation or natural service but could at a minimum be during rectal massage. The South African and ACV systems provide the option of providing a BBSE report with accompanying comments in situations where the penis can only be palpated through the sheath. But the SFT system does not allow a classification of the bull as Satisfactory unless the penis has been visualized.
Scrotal Circumference Measurement
All systems agree that the measurement of SC is a compulsory requirement of the BBSE. Additionally, the systems that provide manuals or accreditation programs (ACV and the SFT) emphasize the importance of correct technique when performing the procedure and provide detailed information on how to obtain reliable measurements. They also highlight the need for adequate practical training to master the skill necessary to obtain repeatable measurements.
The interpretation of the SC measurement varies between regions. The traditional interpretation is based on SFT guidelines, where SC standards are based on bull age, with minimal consideration for breed, body condition, or weight. This is the case for the SFT, South Africa, BCVA, and Canadians utilizing the SFT system. The ACV and WCABP systems introduce more complexity in the interpretation, considering more breed and age categories. An example of how the WCABP system differs from the SFT system is that later maturing breeds such as Limousin, Salers, and Blonde d'Aquitaine have a lower SC threshold of 32 cm at 24 months of age compared to the 34‐cm threshold in the SFT, South African, and BCVA systems. The ACV system also considers body weight at the time of SC measurement, recognizing the effect body weight and body condition have on SC [23]. On this point, the ACV system was unique in that for young sale bulls it emphasized the need to interpret SC measurements considering the relationships between breed, age, and weight. In the ACV manual, there is a detailed table providing this information for five breed‐groups of bulls ranging in age from 12 to 27 months. Consistent with the ACV system moving away from a Pass/Fail approach and more toward a risk assessment paradigm, the SC is simply noted on the top of the report (Figure 7.2), with the veterinary interpretation included in the comments section of the report. The information can still be used by breeders to apply selection pressure, but a low reading does not necessarily result in a fail in that category and the bull may still be suitable for sale for use in a commercial herd if semen assessment and other evaluations meet the standards.
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