Ultrasonographic and morphological sequelae to repeated testicular biopsies in stallions in relation to the lateral branching of the testicular artery

Abstract

Summary The objectives of this study were to investigate the sequelae to repeated testicular biopsies in stallions and to determine if arterial injuries can be prevented. This study was part of a larger project focused on the antispermatogenic effects of an oral contraceptive compound, RTI‐4587‐073(l), which was given to 3 mature Miniature horse stallions, while another 3 received a placebo treatment. Testicular biopsies were taken once before treatment and 3 times after treatment. They were obtained from alternating testes, 2 procedures per testis, 2 samples each time, using a 18 gauge split‐needle core biopsy instrument (penetration depth: 22 mm). Colour Doppler ultrasonography was performed prior to the procedure to detect and thus avoid lateral branches of the testicular artery. Testicular parenchyma was evaluated ultrasonographically just before, and 2–6 h, 3 days and weekly after the biopsies were obtained. Changes in testicular volumes and semen parameters were monitored. All stallions were then castrated and the testes were evaluated for any gross pathology. There was no major scrotal swelling or gross haemorrhage after the procedures. Only mild, focal lesions were found in the testicular parenchyma 3 and 7 days after taking the biopsies. Three lateral branches of the testicular arteries were punctured, but there was no evidence of significant bleeding or other complications associated with these injuries. We conclude that repeated testicular biopsies may be taken from stallions without causing major complications, regardless of a presence or absence of the lateral branches of the testicular artery. Furthermore, we conclude that using colour Doppler ultrasonography to detect the lateral branches of the testicular arteries is unreliable; however, puncturing these vessels during a biopsy procedure does not necessarily result in significant haemorrhage.

Diagnostic Approach to Equine Testicular Disorders

“…Different biopsy techniques have been used in stallions, such as the open method, split-needle biopsy, and needle-punch biopsy. The size of the biopsy instrument used should be chosen according to the size of the testis, and it varies between the recommended 14 g for adult stallions [ 28 ] to 18 g for miniature stallions [ 29 ]. The most commonly used method is the split-needle biopsy (Biopty, Tru-Cut) [ 28 ] ( Figure 5 ).…”

“…The most commonly used method is the split-needle biopsy (Biopty, Tru-Cut) [ 28 ] ( Figure 5 ). Because of the high vascular component of testes, color Doppler ultrasonography can help to identify a good puncture site prior to the procedure [ 29 ]. The stallion is sedated and restrained in a stock.…”

“…Firm compression with sterile gauze for 5 min provides adequate hemostasis. The sample obtained may not be sufficient for a detailed quantitative evaluation of spermatogenesis, and taking more than one sample without removing the needle is advised [ 29 ]. The recovered material can also be used to analyze abnormalities restricted to gene expression [ 30 ] and cDNA mutations analysis in subfertile stallions [ 31 ].…”

Sperm Quality Assessment in Stallions: How to Choose Relevant Assays to Answer Clinical Questions

“…However, this technique may lead to some damage to the spermatozoa, such as separated heads, which will induce misinterpretation [25], and the staining can impair the visualization of small structural details [22]. Lengthening the Diff-Quick staining timings to 5 or 30 min [51,52] can lead to an observed slide quality that is similar to the reference method, but impairs its main interests: the speed and ease of realization. At present, the reference technique for fine morphology analysis is to dilute semen (1v/40v) in 37 • C formaldehyde 4%, to place a 5 µL drop on a 37 • C slide under a covering slide, and then to analyze 200 spermatozoa with contrast microscopy at ×1000 [6,25].…”

Evaluation of testicular echotexture with Ecotext as a diagnostic method of testicular dysfunction in stallions

“…Despite recent studies having shown that repeated testicular biopsy does not result in detrimental effects on prospective fertility [6,7], this invasive technique is not widely used among equine practitioners.…”