Evaluation of Testicular Size and Function In 1-3-Year-Old Stallions

Considerable variation exists in the level of spermatogenic efficiency present in similar sized testes of stallions #3 years of age. Results of 53 breeding soundness examinations of 3-year-old stallions composed of 8 breeds were compiled and demonstrated that scrotal width was only moderately correlated with parameters of semen quality in first or second ejaculates. Equine practitioners should be cautious about making predictions for mare books (number to be bred) without first examining semen quality. Authors’ addresses: College of Veterinary Medicine, Texas AM Nandi Veterinary Associates, 3244 W. Sieling Rd., New Freedom, PA 17340 (Johnson, Brinsko, Varner, Rigby, and Hurtgen). © 2001 AAEP.

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