Semen characteristics after vasectomy in the ram

Application of a laparoscopic technique for vasectomy in standing horses

This report describes a technique for standing laparoscopic vasectomy in stallions through a prospective descriptive study. A preliminary study was carried out with two experimental intact male horses and subsequently the procedure was performed in two clinical cases. These horse owners want to keep their animals in the most possible natural way, preserving its stallion behaviour in a herd without generating offspring. The horses were sedated and restrained in stocks and laparoscopic vasectomy was performed using three portal sites in both paralumbar fossae recording surgical times. A 4-cm segment of each ductus deferens (DD) was occluded with laparoscopic vessel sealing devices and subsequently excised. Semen collection was performed using an artificial vagina before the laparoscopic procedure and at 15 and 60 days postoperatively. Sexual behaviour and spermiogram were analysed. Two months after vasectomy, control laparoscopy was performed in experimental horses to assess the surgical site. Bilateral vasectomy could be performed without intraoperative complications in a mean surgical time of 20 min per DD. Success of the procedure was confirmed in all cases by azoospermic ejaculates 60 days after vasectomy. This is the first time that the technique for laparoscopic vasectomy is described in horses.

Comparative study between the excision-ligation and autoligation of vas deferens technique for teaser rams preparation

AIM

The present study was designed to demonstrate the autoligation (AL) of vas deferens and the excision-ligation (EL) technique to generate vasectomized rams to reduce the complications, operative time, and price of the vasectomy techniques.

MATERIALS AND METHODS

A total of 12 healthy and mature Iraqi Awassi rams were used, which divided into two groups, six rams for each one. The former group was performed the EL technique while the latter group, the AL of vas deferens technique was used.

RESULTS

The results of the present study found that both techniques were same with the reproductive efficient examinations that mean the two techniques had same ability to close the male genital passage for teaser rams preparation. However, the methods were different with the histopathological changes, operation time, prices, and complications, which were minor in the AL of vas deferens compared with the EL technique.

CONCLUSION

The AL technique of vas deferens to prepare teaser animal is recommended over the EL technique due to different aspects such as cost, fewer complications, and active teaser for a long period are the main aspects of AL technique.

Evaluation of morphological criteria of sperm quality before in vitro fertilization and intracytoplasmic sperm injection

The quality of sperm has a direct influence on the fertilization and developmental competence of embryos. In the literature we did not find defined criteria for evaluation of normal sperm parameters in various species of domestic mammals. Therefore we attempted to review evaluation of criteria of morphologically normal human sperm and their abnormalities. All sperm cells observed in the stained sample are classified as normal or abnormal. Any abnormalities in morphology of sperm have a negative effect on the outcome in in vitro fertilization and intracytoplasmic sperm injection. Abnormal sperm are categorized into subgroups according to the observed defects (concerning the head and/or midpiece and/or tail). Most morphologically abnormal sperm have multiple defects. This article can be considered as guideline for the manual of sperm quality evaluation in different species of domestic mammals.

Bilateral epididymal sperm granulomas following urethrostomy in a German shepherd dog

Bilateral enlargement of both epididymes was observed in a 6-year-old German shepherd dog following a pre-scrotal urethrostomy. Testicular parenchyma showed regular structure, and the spermatogenesis and the steroidogenic functions were not modified. However, macroscopic examination of the tail and the body of both epididymes exhibited multiple white and well-delimited foci. Histopathological study of the epididymes confirmed the development of granulomas associated with extravasated spermatozoa. Urethrostomy caused a severe stenosis of the penile urethra, favouring the retention of urine at the urinary bladder. The retrograde pressure exerted by the distension of the urinary bladder could have allowed the urine to reach the prostatic urethra and the deferent ducts and, finally, the epididymes, causing irritation and rupture of the mucous layer of the epididymal duct, the consequent sperm extravasation and the development of sperm granulomas. We speculate that the inadequate surgical resolution of the urethral calculi caused the bladder distension, the subsequent retrograde flow of urine and the development of the lesions.

Pharmacological and toxicological assessment of a potential GnRH vaccine in young-adult male pigs

Active immunization against gonadotrophin-releasing hormone (GnRH) is successfully applied to prevent boar taint in pork. In men, GnRH immunization could be an alternative to hormone therapy in patients with prostate cancer. In this study, a new GnRH vaccine formulation (a modified GnRH peptide conjugate formulated with CoVaccine adjuvant) was investigated for its pharmacological efficacy and safety in young-adult male pigs. Immunization resulted in castrate-like plasma testosterone levels in all treated pigs from week 8 until the end of the study, 30 weeks after the first immunization. Testosterone depletion retarded testes growth, reduced the relative weight of the testes and accessory sex organs, and reduced sperm counts and motility. There was no clinically relevant toxicity. Typical vaccination-related adverse reactions, such as swelling at the injection site and fever, were considered acceptable. We conclude that this GnRH vaccine efficiently and rapidly reduced serum testosterone levels, without inducing chronic toxic effects, and therefore could be applicable in both veterinary and human medicine.

Epididymis ligation: a minimally invasive technique for preparation of teaser rams

OBJECTIVE

To describe a minimally invasive technique for preparation of teaser rams by needle-assisted ligation through the tail of the epididymis.

STUDY DESIGN

Experimental study.

ANIMALS

Mature rams (n=6), estrus-induced ewes (2). METHODS; After local anesthesia, epididymis ligation was achieved by restraining the testis distally within the scrotal sac and passing suture through a hypodermic needle inserted between tail of epididymis and distal pole of testis, caudomedial to craniolateral through the scrotum. The needle was removed leaving the suture in place and the testis pushed up dorsally, then the needle was reinserted through the original holes and the suture passed back through the needle, which was withdrawn. This resulted in the suture forming a complete loop around the epididymis. The suture ends were tied ligating the epididymis. Semen was evaluated pre- and postligation. Testes were removed after 30 days for gross and histologic examination.

RESULTS

Epididymis ligation was accomplished without postoperative complications. Three weeks after the epididymis ligation, no motile and live spermatozoa were found in ejaculates. From 5 to 28 days after epididymis ligation, attraction to ewes and libido was unchanged and similar to 14 days before ligation.

CONCLUSIONS

This novel minimally invasive technique is a simple, alternative method for preparation of teaser rams.

CLINICAL RELEVANCE

This method is simply performed, without skin wounds, and minimal postoperative care is needed. The technique should be readily adaptable to other species.

Semen characteristics and plasma levels of testosterone after bilateral vasectomy in bucks

The effects of bilateral vasectomy on the seminal characteristics were assessed in six bucks of the Canarian breed. In addition, we tried to establish the effects of vasectomy on the plasmatic concentrations of testosterone and the libido of the bucks. Semen samples were collected once a week from 8 weeks before to 16 weeks after vasectomy; blood samples were collected prior to vasectomy, and then at once and 1 week after vasectomy and every 2 weeks from the week 4 to the end of the experiment. One week after the vasectomy, ejaculated spermatozoa were non-motile and the percentage of live spermatozoa was below 5% in all vasectomized males; in addition, the total number of cells/ejaculate was 3100 x 106 and 30 x 106 spermatozoa in the control and vasectomized males, respectively. Our results suggest that the vasectomized males may be used as oestrus detectors, without risks of accidental fecundating, only 1 week after vasectomy. Before vasectomy, no significant differences were observed in plasma levels of testosterone between the vasectomized and control males (5.4 +/- 1.2 and 3.9 +/- 1.4 ng/ml, respectively); from 4 to 12 weeks after vasectomy, a marked decrease in the testosterone concentration in all males (vasectomized and control bucks) was observed. From 12 weeks after vasectomy until the end of the experiment, four of the vasectomized males and the control males recovered their normal libido. The results suggest that vasectomy did not exert a remarkable effect on the steroidogenic functionality of the testicle.

Analysis of the pathogenetic basis for shedding and transmission of ovine gamma herpesvirus 2

Ovine herpesvirus 2 (OvHV-2), a member of the viral subfamily Gammaherpesvirinae, shares numerous similarities with human herpesvirus 8 (HHV-8). Both viruses are apathogenic in their healthy original host, may cause lymphoprolipherative diseases, cannot routinely be propagated in cell culture, and may be sexually transmitted. However, the pathways of sexual transmission of these viruses, as well as the underlying pathogenetic dynamics, are not well understood. Organs from naturally OvHV-2-infected, as well as OvHV-2-free, sheep were quantitatively analyzed for OvHV-2 by the DNA amplification techniques. The dynamics of OvHV-2 multiplication and excretion were monitored after experimental infections and, most importantly, subsequent to vasectomy. The OvHV-2 DNA load in various tissues and internal organs was not merely reflecting the viral DNA load in the bloodstream, which suggested compartmentalization of OvHV-2. Moreover, OvHV-2 DNA was detected at several portals for virus shedding, i.e., the respiratory, alimentary, and urogenital tracts. Transient OvHV-2 excretion was detected in ejaculates of experimentally infected rams. Upon vasectomy, OvHV-2 DNA reappeared in the ejaculatory plasma, but the titers did not decline after reaching a peak. Spiking and fractionation experiments revealed an inhibitory activity, associated with the spermatozoa, which was able to suppress detection of viral DNA but which was no longer present in samples from vasectomized animals. Therefore, epidemiological studies on viruses that may be transmitted by the ejaculatory pathway and for whose tracing nucleic acid amplification methods are used, i.e., OvHV-2, HHV-8, and the human immunodeficiency virus, should include vasectomized males.