Rapid disappearance of spermatozoa after vasal occlusion in the dog

A novel laboratory procedure to validate American Urological Association guideline on vasectomy success and to diagnose obstructive azoospermia

The objective was to develop a laboratory procedure to validate American Urological Association (AUA) Guideline on vasectomy success when nonmotile spermatozoa are found in the post-vasectomy ejaculate. The neutral α-glucosidase (NAG) an epididymal protein assay modified to determine the activity at 30 and 90 min of incubation from 24 pre- and 47 post-vasectomy ejaculates. The difference between the two points in the relative activity was calculated and if the difference was nonsignificant will confirm vasectomy success. The mean differences in the relative NAG activity were significantly different in pre- and post-vasectomy ejaculates, respectively. The mean differences in the relative NAG activity were similar in post-vasectomy ejaculates with and without nonmotile spermatozoa. No difference in relative NAG activity in post-vasectomy ejaculates between two time points of incubation may be a reliable method to confirm occlusion of the vas deferens. It also validates the recommendation by AUA Guideline on vasectomy success in the presence of few nonmotile spermatozoa.

Gonad-Sparing Surgical Sterilization in Dogs

Elective sterilization of pet dogs is a common surgical procedure performed in veterinary practice. The main benefit of sterilization is population control and the reduction in euthanasia of unwanted dogs. The most common methods for sterilizing female and male dogs are ovariohysterectomy (spay; which removes both the ovaries and the uterus) and castration (neutering; which involves removing the testicles), respectively. However, any surgery that removes the gonads changes the animal in both positive and negative ways. There is mounting evidence supporting the long-term health complications associated with surgical sterilization with gonad removal. Gonads are not merely gamete-producing or ancillary sex/reproductive organs but rather they are necessary endocrine glands for normal metabolic, behavioral, musculoskeletal, and anti-neoplastic health. The purpose of this mini review is to describe two gonad sparing surgeries that this author has used to sterilize dogs. These surgeries can be performed on pediatric patients without interfering with pubertal maturation. Dog owners can make the decision when the dog is completely mature whether or not the gonads should be removed.

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.

Comparison of postoperative complications in healthy dogs undergoing open and closed orchidectomy

OBJECTIVE

To compare closed and open orchidectomy in dogs and the associated complications.

METHODS

A randomised controlled blinded prospective clinical study of 73 cases was undertaken involving the recording of all complications during and in the 10 days following orchidectomy of dogs fulfilling the standardised inclusion criteria. The active variable was the surgical technique of either open or closed orchidectomy.

RESULTS

Dogs undergoing open orchidectomy experienced significantly more complication events than the dogs undergoing closed orchidectomy [24 of 34 (70%) versus 18 of 39 (46%), P = 0 · 04]. Dogs undergoing open orchidectomy were statistically more likely to develop scrotal complications (21 of 34, 61%) compared with dogs undergoing closed orchidectomy (13 of 39, 33%; P = 0 · 02).

CLINICAL SIGNIFICANCE

Open orchidectomy is associated with a higher overall complication rate in the first 10 days after surgery than closed orchidectomy. Open orchidectomy is also associated with increased scrotal complications including swelling, bruising and pain compared with closed orchidectomy.

Porcine vas deferens luminal pH is acutely increased by systemic xylazine administration

Data are accumulating to demonstrate that pH regulation in the male reproductive tract has a vital role in modulating sperm cell fertilizing capacity, and therefore male fertility. Bicarbonate uptake by sperm cells is required for the achievement of motility levels required for fertilization. Vas deferens epithelial cells can carry out measurable bicarbonate secretion, but the available literature to date reports that the vas deferens luminal content is typically acidic. This study aimed to determine pH in the boar vas deferens lumen and whether modulatory mechanisms exist for regulation of pH in this compartment of the male reproductive tract. A fiberoptic pH probe was used to assess pH in the vas deferens of anesthetized adult boars. The mean pH, derived from multiple measurements at variable positions along the vas deferens lumen, was 7.39 +/- 0.09. Furthermore, administration of xylazine, an alpha-2 adrenergic receptor agonist rapidly (<10 min) alkalinized the vas deferens lumen in most cases. Because the duct was transected proximal to the site of measurements, the observations rule out the possibility that alkalinization resulted from secretion in more proximal portions of the duct. These results indicate that the boar vas deferens lumen can be alkaline, and they suggest that porcine vas deferens epithelia increase net bicarbonate secretion in vivo after systemic alpha-2 adrenergic stimulation. This secretory response greatly changes the luminal environment to which sperm cells are exposed, which will initiate or enhance motility, and is expected to modulate male fertility.

Vasectomy effect on canine seminal plasma biochemical components and their correlation with seminal parameters

Three semen samples were collected at 48 h intervals from 20 mature research dogs previously conditioned to manual semen collection. Vasectomy was performed in all dogs, and 15 days after surgery, another three ejaculates were similarly collected. The semen was evaluated, and centrifuged to obtain seminal plasma for measurement of pH, and concentrations of total proteins (TP), total chlorides (Cl), calcium (Ca), potassium (K), and sodium (Na). The seminal plasma protein profile was evaluated by SDS-PAGE; molecular weights and the integrated optical density (IOD) of each band were estimated. There was a negative correlation between K concentration and progressive motility (r = -0.49, P = 0.027), sperm vigor (r = -0.60, P = 0.0053), and plasma integrity, evaluated by both the hypo-osmotic swelling test (r = -0.50, P = 0.026) and a fluorescent stain (r = -0.45, P = 0.046). Positive correlations between Na and K pre- and post-vasectomy (r = 0.88, P < 0.001; r = 0.56, P < 0.01, respectively) were verified. There were a total of 37 bands pre-vasectomy and 35 post-vasectomy (range, 100.6-3.6 kDa). Bands B9 and B13 (42.6 and 29.2 kDa) were not present post-vasectomy. The IOD of band B3 (73.5 kDa) was higher (P = 0.03) pre-vasectomy, compared to post-vasectomy; conversely, the IODs of bands B29 and B37 (7.8 and 3.6 kDa) increased (P = 0.026 and 0.047). Pre-vasectomy, there was a positive correlation (r = 0.49, P = 0.029) between band B37 band (3.6 kDa) and the Na:K ratio. In conclusion, K appeared to be involved in sperm motility in dogs and could be a tool to evaluate sperm function. The prostate contributed several elements to canine seminal plasma. Vasectomy changed Ca concentrations and the protein profile of the seminal plasma. Further studies must be performed to clarify the function of these elements on the in vivo fertility of dogs.

Surgical methods of contraception and sterilization

Many techniques for surgically sterilizing dogs and cats have been described; each technique offers advantages and disadvantages to both the patient and surgeon. Techniques that have been described include traditional midline ovariohysterectomy, lateral flank ovariohysterectomy, castration, early age gonadectomy, ovariectomy, laparoscopic ovariohysterectomy and ovariectomy, and vasectomy. Regardless of the technique selected, strict adherence to sound surgical technique and asepsis is mandatory for good surgical outcome with minimal complications. This review will discuss surgical principles, complications, outcomes, as well as relevant current literature associated with each of these techniques of surgical sterilization.