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Within the USA, the SFT has taken leadership in the development of BBSE data collection, recording, interpretation, and reporting. Having been in development for more than 60 years [7], the processes employed by the SFT have also served to set a standard for performing the BBSE worldwide. While there is always concern regarding truncated or poorly executed examinations [8], veterinarians in the USA have long had access to clear guidelines for performing the BBSE procedure. The SFT BBSE process has evolved through three main iterations over the past five decades [8–10]. The most recent progression came in 2018 with the production of an updated manual containing evidence‐based information for veterinarians on the BBSE process [10]. One of the stated aims of this document is to instil a belief in cattle producers and veterinarians in the integrity of the veterinary BBSE process. This sentiment seems to be a recurring theme for BBSE practice throughout the world.

Due to the commonality in basic procedures throughout the different regions, a detailed coverage of the SFT BBSE form as described in the SFT BBSE manual is presented [10], as it provides an overview of the type of information recorded in all regions.

The SFT BBSE process offers reporting options in either hard‐copy or electronic form. The form can be broken down into sections as shown in Figure 7.1, with the first section consisting of the client's information and general information about the bull including age, breed, and identification. The name or ear tag of the bull along with some form of permanent identification (tattoo, hot brand, freeze brand, electronic identification (EID) tag number, or United States Department of Agriculture (USDA) official metal ear tag) is included. The age of the bull is recorded in months up to two years of age to ensure SC measurements are categorized and interpreted correctly in young bulls.

Figure 7.1 The SFT electronic BBSE form.

Source: From Society for Theriogenology, Bull Breeding Soundness Evaluation form. © 1992, The Society for Theriogenology.

Below the client and bull information, a box is provided to record any known history about the bull's fertility or medical history. Practitioners utilizing the SFT electronic BBSE software can allow automatic filling of this box with the bull's previous breeding soundness examination if it was completed in the software. At the bottom of the box there is a statement regarding the fact that the responsibility is on the producer to evaluate the libido and mating ability of the bull when placed with females.

The next section of the form is the physical examination portion of the examination and begins with the body condition score. The scale for both beef and dairy bulls is present on both form types, with consideration given to the score as well as circling the appropriate descriptor of obese, good, moderate, or thin. The physical examination is completed with the assessment including examination of the bull's eyes; conformation including feet and legs; examination of the scrotum, testes, and epididymides; SC measurement; transrectal examination of the accessory sex glands and internal inguinal rings; and examination of the penis and prepuce during the ejaculation process. Each item has an open box beside it to be checked following examination to indicate that the item was assessed and found to be without abnormalities. If an abnormality is noted, an explanation of the abnormality is placed in the box to the right of the checkbox.

SC is part of the reproductive physical examination and is recorded in centimeters just below the physical examination checkboxes on the form. Tables of the expected SC by age are given on the back of the form. In the SFT system, a bull with an SC below the minimum cannot receive the classification of satisfactory potential breeder even if the rest of the physical examination is passed and semen quality is satisfactory.

When filling in the semen examination portion of the form, the method of semen collection is marked, followed by whether the bull obtained erection, full protrusion of the penis, and ejaculation. Protrusion of the penis and examination of the prepuce is essential before deeming a bull a satisfactory potential breeder in this system.

The SFT manual provides good detail on preparing semen for evaluation so that repeatable results can be achieved. These guidelines describe the common requirement to dilute concentrated samples in order to assist visualization of individual spermatozoa for motility assessment. But there is little detail on the practicalities of the dilution process and dilution rates.

The SFT lower threshold for individual motility is set at 30%. It is notable that the measurement of gross motility is no longer recommended as part of the BBSE semen assessment process in the current SFT guidelines.

The SFT no longer classifies morphology defects as primary/secondary or major/minor, but simply records them as they are seen. They are then grouped into Normal or Abnormal Head, Midpiece, and Tail categories for the report. If there is a high percentage of abnormal sperm, notes on what was found are made in the comments. The SFT lower threshold for normal sperm is 70%.

Following the evaluation, the data are interpreted and the bull is classified into one of three categories – satisfactory potential breeder; classification deferred; or unsatisfactory potential breeder. The classification deferred category is used when potentially treatable abnormalities are detected, or when the practitioner considers that aberrations to the spermiogram may be related to a specific insult and time is needed for recovery.