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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.
Perhaps the most influence these variations in SC interpretation have on the outcome of the BBSE can be attributed to whether the information is used for a direct assessment of whether the bull is ready to join the breeding herd on a given date or whether the information is being used to leverage fertility selection pressure. In this context, a direct measurement regardless of age, weight, or breed would provide useful information on whether a bull is mature and suitable to be introduced into the breeding herd on a given date. In contrast, if information is to be used to generate accurate selection data, variably referred to as estimated breeding valuations (EBVs) or expected progeny differences (EPDs), then interpretation based on weight, age, and breed become important.
These variations on how the SC information can be used leads to the need to be clear on the purpose for which the BBSE is being performed. The argument could be made that the primary purpose of the BBSE is to determine if an individual bull is suitable for purpose on a specific date. In this instance, a one‐off SC measurement close to the time of entering the breeding herd may be suitable. Conversely, the question is raised of whether it is the role of the veterinarian to fail a bull that is producing semen of acceptable quality if the SC measurement, often taken without important context such as accurate age, breed, weight, and body condition score information, doesn't meet the threshold.
Bull‐Side Semen Evaluation
All standards recommend the collection of semen as part of the routine BBSE. However, not all standards explicitly state semen evaluation as a compulsory element of the examination. The ACV standards provide for the option of no semen evaluation, but mandate the compulsory reporting on their certificates of whether semen assessment is included in the evaluation.
For most regions, there was the option for assessment of gross motility (mass activity), apparently based on tradition. But in regions where standards were accompanied by a manual, practitioners were cautioned against using this parameter as part of the BBSE. Notably, the SFT no longer recommends the use of gross motility as part of the semen assessment process and has now removed it from the BBSE form.
All regions recommend assessing individual motility as a compulsory aspect of the BBSE. In regions where manuals are available there is clear recognition that individual motility is readily affected by artifact. To counteract this, detailed procedural guidelines are provided including the requirement for clean, warmed contact surfaces, the use of a binocular microscope, and the recommendation to dilute the semen to ensure the activity of individual cells can be readily assessed. Two of the four regions recommending semen dilution prior to motility assessment provide explicit guidelines for this dilution process, where semen is recommended to be diluted to turbid consistency (between 60 and 200 million/ml) with warmed phosphate buffered saline to ensure repeatable estimates [16, 23]. In the Netherlands, the recommendation is for a 1 : 80 dilution of semen to diluent, providing sperm concentrations of less than 20 × 106 for assessment.
Variation exists in the interpretation