Stallion Scrotal Calipers

Stallion Scrotal Calipers are used during a stallion breeding soundness exam to measure the total scrotal width. The Calipers may be adjusted with one hand and will hold their position for later recording of the measurement.

Scrotal Calipers  are designed to measure total scrotal width (T.S.W.), which includes both testes. It also can be used to measure the length and width of each teste. Since T.S.W. provides a reasonably accurate estimate of testicular size, it is the measurement most commonly used during a fertility examination.

The number of spermatozoa that a stallion is capable of producing depends largely on amount of functional testicular tissue. Therefore, testicular size becomes an important factor in selecting and managing a stallion for maximum reproductive efficiency. Assuming testicular consistency is satisfactory, T.S.W. can be used to estimate sperm production and output. This aids in identifying individual stallions with a potentially high or low sperm production, which assists in the prediction of how many mares can be bred in natural or artificial insemination (A.I.) programs. Testicular size varies primarily with age, health and season of the year. Therefore, for prudent management, a breeding stallion's T.S.W. should be measured once per month and the results added to the stallion's permanent medical record. For maximal benefit, the estimate must be accompanied by the results of a testicular palpation. The description of each palpated testis could include: normal, soft, firm, hard, inconsistent, nodular, lobulated, ribbed, veined (slightly or heavily), degenerating, small, large, slick, rotated, rough, constrictions, flat, irregular, high and/or missing. 

The Stallion Scrotal Caliper is made of a light-weight, durable plastic. The scale is in centimetres and ranges from 5 to 15 in graduations of 0.2 centimetres. The T.S.W. of normal stallions, averaged across breed, age and season, is 10.8 centimetres.