Advanced Stallion Evaluation

Evaluation of the Male Genitalia

Stallion Evaluation

The equine veterinary reproduction service at UF offers a wide range of advanced equine breeding techniques in evaluating external and internal genitalia in stallions, such as ultrasonography, color doppler modality, testicular biopsy, and urethral endoscopy (urethroscopy). Contact us to schedule an appointment.

Our board certified specialists are experienced in performing ultrasound evaluation of scrotal contents, including testes, epididymides, and spermatic cords. Furthermore, color doppler modality is used to detect early changes characteristic for neoplastic process (tumor growth), inflammation, trauma or ischemia (impaired blood flow). This technique is also applied in evaluating penile function after trauma or chronic inflammatory process.

In order to diagnose testicular tumors or advanced degeneration, a sample of testicular tissue has to be obtained and evaluated under a microscope. The specialists in Large Animal Reproduction at the University of Florida have extensive experience and skills in performing testicular biopsies in stallions using the least traumatic techniques. Ultrasound guidance helps us effectively target areas of interest, and color doppler modality allows visualization of large vessels, which have to be avoided during this procedure.

  • Transrectal ultrasound examination is necessary to detect pathologies of the internal genitalia in stallions. This technique is especially helpful in diagnosing mechanical occlusions of the ejaculatory apparatus. We perform this evaluation during routine breeding soundness examinations of all stallions presented to our clinics as a screening exam, as well as on stallions showing specific symptoms, such as ejaculatory dysfunctions, poor semen quality, and the presence of inflammatory cells or blood in the semen.
  • Urethroscopy is a technique used to visualize the urethra from the inside using a fiberoptic instrument (endoscope). The endoscope used for urethroscopy in stallions is similar to one used for evaluating a horse’s stomach, but has a smaller diameter. We use this technique to evaluate a stallion’s urethra for inflammation, tears, and neoplastic (cancerous) changes. It helps us in detecting a source of bleeding and inflammatory cells in semen. It is also used to deliver treatments directly to the vesicular glands in cases of infections.

Advanced Semen Analysis

Equine Reproduction

Our laboratory is well-equipped with state of the art microscopes, including phase-contrast and fluorescence microscopes, spectrophotometer, and computer assisted sperm analyzer (CASA). Phase-contrast microscopy is used in assessing morphological defects of spermatozoa. Florescence microscopy is also available for detecting more subtle and difficult to detect abnormalities of stallion spermatozoa associated with subfertility, such as dysfunctional acrosome. Furthermore, we have capabilities to objectively evaluate motility of spermatozoa in semen (CASA) collected from stallions. Analysis of a path of sperm movement may be helpful in detecting a specific problem, such as premature hyperactivation of sperm.

Equine Reproductive Behavior Evaluation

A large portion of fertility problems in stallions is associated with behavioral symptoms. Reproductive behavior problems can be frustrating to horse breeders, and may be devastating to a stallion’s breeding carrier. Some issues are:

  • Low libido
  • Mounting difficulties
  • Ejaculatory dysfunctions
Stallion Reproduction

UF Equine Reproduction offers a comprehensive evaluation of such problems, treatment of the underlying cause, and management of stallions with behavioral dysfunctions. A primary focus is placed on diagnosis of any physical problem, which can be a root cause of stallion’s behavioral dysfunction, such as: musculoskeletal pathology, occlusion of the ejaculatory apparatus, or painful testicular or epididymal abnormality. These diseases are often treatable and behavioral symptoms are resolved after appropriate treatment has been implemented. Other behavioral issues in breeding stallions may be psychological in nature and require a series of therapy sessions based on behavioral modifications.

Our team has skills and patience necessary to re-train such stallions in order to return them to full functionality. Furthermore, we train novice stallions to semen collections off a mare or off a phantom. We also can collect semen using various alternative techniques, such as: ground collection, manual collection, or pharmacologically induced semen collection, if needed.

Return to UF Equine & Large Animal Reproduction.

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