Decision Making for Cryptorchid Castration; a Retrospective Analysis of 280 Cases

The location of an undescended testicle influences the choice of surgical technique for efficient cryptorchid castration. We review a standardized protocol for preoperative examination to dictate surgical approach to cryptorchidism. Cases are split into two periods: 2004–2006 and 2007–2014. In 2004–2006, conventional cryptorchidectomy and laparoscopic cryptorchid castration (standing) were both offered, but the choice of technique was based primarily on owners' preference for a recumbent or standing procedure. In 2007–2014, ultrasonography was used to locate the testes and dictate the preferred surgical approach; for abdominal testes, laparoscopic intraabdominal spermatic cord ligation without orchidectomy was preferred and for inguinal testes, conventional open orchidectomy. The numbers of animals requiring a second procedure to complete castration were compared between the two periods. In addition, failure rates for individual testes grouped by location were determined separately for the different techniques, and the value of preoperative ultrasonography to locate the retained testes was assessed. In 2004–2006, 15.3% (20/131) of the cryptorchids needed more than one surgery to complete castration, compared to 0.7% (1/144) in 2007–2014. Failure rates for laparoscopic castration were 0/168 (0%) for abdominal, 3/40 (7.5%) for inguinal, and 9/55 (16.4%) for scrotal testes; for conventional castration, failure was recorded for 3/12 (25%) abdominal and 0/92 (0%) inguinal testes. For 94% (156/166) of retained testes, ultrasound-based preoperative advice on surgical approach was correct. Using a standardized preoperative examination to determine choice of surgical technique significantly (P < .001) reduced the number of second surgeries needed to complete castration. Preoperative ultrasound is therefore a useful aid to determining the surgical approach to cryptorchid castration.     

Equine castration: review of anatomy, approaches, techniques and complications in normal, cryptorchid and monorchid horses

Complications associated with equine castration are the most common cause of malpractice claims against equine practitioners in North America. An understanding of the embryological development and surgical anatomy is essential to differentiate abnormal from normal structures and to minimise complications. Castration of the normal horse can be performed using sedation and regional anaesthesia while the horse is standing, or under general anaesthesia when it is recumbent. Castration of cryptorchid horses is best performed under general anaesthesia at a surgical facility. Techniques for castration include open, closed and half-closed techniques. Failure of left and right testicles to descend occurs with nearly equal frequency, however, the left testicle is found in the abdomen in 75% of cryptorchid horses compared to 42% of right testicles. Bilateral cryptorchid and monorchid horses are uncommon. Surgical approaches described for the castration of cryptorchid horses include an inguinal approach with or without retrieval of the scrotal ligament, a parainguinal approach, or less commonly a suprapubic paramedian or flank approach. Laparoscopic castration of cryptorchid horses has recently been described but the technique has limited application in practice at this time. A definitive diagnosis of monorchidism can only be made after surgical exploration of the abdomen, removal of the normal testis and hormonal testing. Hormonal assays reported to be useful include analysis of basal plasma or serum testosterone or oestrone sulphate concentrations, testosterone concentrations following hCG stimulation, and faecal oestrone sulphate concentrations. Reported complications of castration include postoperative swelling, excessive haemorrhage, eventration, funiculitis, peritonitis, hydrocele, penile damage and continued stallion-like behaviour.     

Electroejaculation and artificial insemination in Vietnamese potbellied miniature pigs

A 15-month-old Vietnamese miniature boar was examined because of suspected infertility. A breeding soundness examination was conducted, using electroejaculation under anesthesia for semen collection. Semen values were normal despite a subpubic location of the testes. Artificial insemination of a gilt with extended semen resulted in the birth of a litter 111 days later. Vietnamese potbellied boars have small and sometimes nearly undetectable scrotal pouches, which may cause the producer to question the fertility of the boars.     

Results and complications of a novel technique for primary castration with an inguinal approach in horses

Reasons for performing study: Complications associated with equine castration can have medical and financial consequences. This retrospective study investigated a novel method of castration via an inguinal approach in mature stallions and compared the incidence of complications with other methods. Hypothesis: Castration via an inguinal approach has a low complication rate at the site of surgery compared with other castration techniques. Methods: Mature stallions (n = 238) were castrated under general anaesthesia in dorsal recumbency using an inguinal approach. The vaginal process was incised, the spermatic cord ligated twice and the testis removed. After suturing, the vaginal process and one or 2 layers of fascia, the subcutis and cutis were closed in a simple continuous pattern. Results: Five of 238 (2.1%) horses had post operative haemorrhage and a haematoma in the scrotal region, which required additional treatment. All horses made a full recovery. Five of 238 (2.1%) of the horses had a post operative respiratory infection, which resolved with antibiotic therapy. Sixteen of 238 (8.8%) had transient signs of colic shortly after surgery. Conclusion: This technique of castration with an inguinal approach had a low incidence of complications at the site of surgery compared with other methods. An inguinal approach and leaving the vaginal tunic in situ may cause less soft tissue trauma than a scrotal approach.     

Bilateral intracorporeally sutured inguinal herniorrhaphy using 3-dimensional laparoscopy in a dog

A 7-month-old, intact male, mixed breed dog with bilateral inguinal hernias underwent general anesthesia for laparoscopic bilateral inguinal herniorrhaphy via a 3-port approach. A 3-dimensional laparoscopic system was used to perform the procedure immediately following prescrotal open castration. Intracorporeal suturing with polypropylene was performed, and 2 cruciate sutures were placed to close each inguinal ring. The caudal aspect of each inguinal ring was left slightly open so as not to disrupt the passage or patency of vessels and nerves. No intra- or post-operative complications occurred. One year after surgery, the dog has no evidence of recurrence of the inguinal hernias.Key clinical message:This case report demonstrates a novel minimally invasive approach to inguinal herniorrhaphy in a dog with no reported complications and a good long-term outcome. Intracorporeally sutured inguinal herniorrhaphy is feasible in dogs with good results, although additional cases are needed to gain experience with this technique in dogs with varying presentations of inguinal hernias.     

Midline scrotal ablation technique for unilateral cryptorchid castration in horses

Thirty-nine unilateral cryptorchid horses were castrated, using a midline scrotal ablation technique. This approach was satisfactory to access both inguinal rings, to eliminate the need for 2 incisions, and to allow for completion of the surgery by primary closure. These horses recovered from surgery with few complications, returned to work promptly, and had excellent cosmetic results.     

Laparoscopic-assisted cryptorchidectomy in 2 Vietnamese pot-bellied pigs (Sus scrofa)

This report describes laparoscopic-assisted cryptorchidectomy in 2 Vietnamese pot-bellied pigs. Abdominal access was obtained by a modified-Hasson technique allowing for placement of a 6 mm laparoscopic trocar-cannula assembly. Following carbon dioxide insufflation, 2 para-preputial 6 mm instrument portals were established. The cryptorchid testicle was extracted from the abdomen following enlargement of the para-preputial instrument portal and cryptorchidectomy was performed extra-corporeally.     

Normal and cryptorchid castration

Surgical exploration of the horse that has presumably had a normal castration or a previously successful cryptorchid surgery remains a distinct challenge. No hard and fast rules dictate a proper course of action for each case. If a horse was anesthetized for routine castration, discovered to have only one scrotal testis, had a brief exploratory on the nondescended side and was recovered, trauma to the inguinal region would probably be sufficiently minimal that an inguinal approach could be used at subsequent exploratory surgery. If the inguinal canal was extensively manipulated and the tail of the epididymis was inadvertently removed, however, one of the alternate approaches would be advisable. Where previous history is unknown, external and rectal palpation, hormonal assays, and careful evaluation of the scrotal/inguinal scars under anesthesia are advisable prior to proceeding with a specific course of action. As previously cited, "one hopes for the best but prepares for the worst." Where inguinal canals are being explored in the supposedly previously castrated horse that still has aggressive male behavior, the surgeon is searching for vaginal process and contents or the stump of the spermatic cord. If the stump is identified to suggest complete previous castration, the stump should contain cremaster muscle, parietal vaginal tunic, testicular vessels, and ductus deferens. If a second nonvascular tubular structure is found but no testicular vessels are found, the tail of the epididymis was inadvertently removed and assumed to be hypoplastic testis. This determination can be difficult to make on gross observation of the stump. Again, a thorough case workup helps one plan in advance for what should be found at surgery.     

Comparison of the diagnosis and management of unilaterally castrated and cryptorchid horses at a referral hospital: 60 cases (2002-2006)

OBJECTIVE: To determine the incidence of unilaterally castrated horses among horses admitted to the hospital for castration and to compare horses that underwent previous unilateral castration with horses that had cryptorchism. DESIGN: Retrospective case series. ANIMALS: 16 unilaterally castrated horses and 44 cryptorchid horses. PROCEDURES: Medical records of horses that were admitted to the veterinary medical teaching hospital for castration, including cryptorchid and unilaterally castrated horses, between January 2002 and December 2006 were reviewed. Medical records of unilaterally castrated horses and cryptorchid horses were examined for age, breed, history, diagnostic procedures, surgical technique of cryptorchidectomy, location of the retained testicle, and cost of surgery. RESULTS: Of 160 horses admitted for castration, 16 (10%) had undergone previous unilateral castration and 44 (27.5%) had cryptorchidism. Unilaterally castrated horses were significantly older than cryptorchid horses. No significant difference was found in left versus right distribution of testicles. No significant difference was found in abdominal versus inguinal distribution of left-sided testicles. Unilaterally castrated horses had a significantly lower proportion of right inguinal testicles, compared with cryptorchid horses. The cost of diagnosis and management of unilaterally castrated horses was significantly greater than in cryptorchid horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the distribution of retained testicles is significantly different in unilaterally castrated horses, compared with cryptorchid horses, which may affect the selection of diagnostic and surgical approaches to unilaterally castrated horses.     

Laparoscopic intra-abdominal ligation of the testicular artery following castration in a horse

A 364-kg (800-lb) 1-year-old mixed-breed horse was admitted for treatment of uncontrolled bleeding after castration. Multiple attempts to ligate the testicular artery through the scrotal incisions prior to referral had been unsuccessful. Because of the owner's concerns about cost, an attempt was made to control the bleeding by applying pressure to the inguinal region and administering formalin IV. However, hemorrhage continued. A decision was made to use laparoscopy to ligate the testicular artery. The horse was anesthetized and positioned in dorsal recumbency, and a routine ventral laparoscopic approach was used. The horse recovered without further complications. Laparoscopy should be considered for ligation of the testicular artery in horses with uncontrolled bleeding after castration.     

Morphological and immunohistochemical studies in testes of normal and cryptorchid boars

Scrotal (n = 66), inguinal (n = 7) and abdominal (n = 36) testes from pigs differing in age (from 1 day to 4 years) were collected after slaughtering or by castration, fixed in 4% formalin and examined by light microscopy. The expression of vimentin, desmin, alpha-actin and PCNA was detected by immunohistochemical technique. Histologically no differences between scrotal and cryptorchid testes are obvious during the prepubertal period, until the age of 10-12 weeks, but with the onset of puberty degenerative alterations (Sertoli-cell-only morphology, giant cells) in dystopic testes occur. Additionally the differentiation of the interstitial cells is disturbed in abdominal testes resulting in a deviating expression pattern of alpha-actin. The Sertoli cells show different distribution patterns (basal, perinuclear, apical) of vimentin depending on the position of the testis and the age of the animal.     

Inguinal-Scrotal Urinary Bladder Hernia in an Intact Male Domestic Rabbit (Oryctolagus cuniculus)

An 8-year-old intact male dwarf rabbit (Oryctolagus cuniculus) was presented with a 2-month history of unilateral scrotal swelling. The external physical examination of the rabbit patient confirmed the severe, unilateral, fluid-filled scrotal distention. Radiographic images of the effected scrotum revealed a soft tissue swelling in the area of the left testicle, and the absence of the urinary bladder in the caudal abdomen. Ultrasonography verified the presence of a fluid-filled mass in the scrotum, enveloping the left testicle. A fine-needle aspiration of the scrotal mass yielded urine, thus a diagnosis of a nonreducible herniation of the urinary bladder into the scrotum was made. An inguinal herniorrhaphy was performed, and the bladder was successfully reduced into the abdominal cavity. A bilateral routine castration and left scrotal ablation were also performed. Two months after surgery no recurrence was noted, and the patient had normal urinary function. Inguino-scrotal bladder herniation is rare in both humans and animals. Male rabbits are predisposed to inguinal and scrotal hernias because their inguinal rings remain open throughout life. Herniation of the urinary bladder should be considered as a differential diagnosis when intact male rabbits are presented with unilateral scrotal swelling.     

Effect of local scrotal heating on the expression of tight junction‐associated molecule Occludin in boar testes

The aim of this study was to determine whether local scrotal heating (42°C, for 1 hr) had an effect on the expression of tight junction (TJ)‐associated molecule Occludin in boar testes. Adult boars (Landrace, n = 6) were used and randomly divided into two groups (n = 3 each). Three boars were given local scrotal exposure to 42°C for approximately 1 h with a home‐made electric blanket of controlled temperature as local scrotal heating group, the other three boars received no heat treatment and were left at standard room temperature as control group. After 6 hr, all boars were castrated and the testes were harvested. qRT‐PCR, Western blotting and immunohistochemistry were used to explore the expression and localization of Occludin. qRT‐PCR and Western blotting showed that the protein and mRNA levels of Occludin significantly decreased in local scrotal heating group as compared to the control. Furthermore, immunoreactivity staining of Occludin was localized at the sites of the blood–testis barrier (BTB) and formed an almost consecutive and strong immunoreactivity strand in the control, while Occludin was limited to Sertoli cells (SCs) and no obvious immunoreactivity strand was present in local scrotal heating group. These data indicated that local scrotal heating decreased the expression of TJ‐associated molecule Occludin, which may be involved in heat‐induced spermatogenesis damage.     

Use of an inguinal approach adapted from equine surgery for cryptorchidectomy in dogs and cats: 26 cases (1999-2010)

OBJECTIVE-To determine whether a surgical technique used in cryptorchid horses can be used successfully to remove testicles retained in the inguinal region or abdominal cavity in dogs and cats. DESIGN-Retrospective case series. ANIMALS-22 dogs and 4 cats with cryptorchidism. PROCEDURES-In 1999 through 2010, 26 cryptorchid patients underwent surgery during which an incision was made over the inguinal ring and the undescended testicle was located for removal via identification of the vaginal process and the embryonic gubernaculum. Castration was performed once a testicle was located in the inguinal region or via removal of an intra-abdominally located testicle through the inguinal canal. RESULTS-4 dogs and 1 cat were bilaterally cryptorchid. Testicles were retained in the abdominal cavity in 18 dogs and in the inguinal region in 4 dogs; in all 4 cats, undescended testicles were located in the inguinal region. Twenty-one dogs and 4 cats were castrated without breaching the abdominal cavity; in one of those dogs, the inguinal ring was enlarged to permit extraction of a tumorous testicle. In 1 dog, the inguinal ring was enlarged into a paramedian laparotomy and viscera were manipulated to exteriorize an intra-abdominally located testicle because the gubernaculum had ruptured. Major intraoperative or long-term complications did not occur. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that as in horses, the surgical approach over the inguinal ring, wherein the vaginal process and the remnant of the gubernaculum are identified and used to locate an undescended testicle for removal, can be used successfully in dogs and cats.     

Morphological and genetic analysis of Vietnamese Sus scrofa bones for evidence of pig domestication

In the present study, we used morphological and genetic analyzes to distinguish bones of domestic boars from those of wild boars. We analyzed 65 Sus bones (cranium, mandible and teeth) stored in three research institutes in Vietnam and in a village in Vietnam. Based on comparison of bucco‐lingual measurements of mandibular parts, the 58 specimens were morphologically classified into two size groups: a large bone group and a small bone group. Analysis of 572‐bp mitochondrial DNA (mtDNA) sequences indicated that the large bones had genetic links to wild boar lineage including Ryukyu, Taiwan and Korean wild boars, and that the small bone group was closely related to East Asian domestic pigs. The phylogenetic analysis and parsimonious networks constructed among mtDNA haplotypes belonging to Ryukyu wild boar lineage showed that the Ryukyu wild boar is closely related to the Vietnamese wild boars, and uniquely miniaturized on their islands after the Ryukyu archipelago became isolated from the Asian continent.     

Cystic Rete Testis in a 3-Year-Old Gypsy Vanner Colt: A Case Report

A 3-year-old Gypsy Vanner colt was presented at the Auburn University College of Veterinary Medicine for castration. The left testicle of the horse was present within the scrotum, but neither the right testicle nor the epididymis was found during external palpation of the right inguinal ring. Removal of the retained testicle by a routine inguinal approach by traction on the gubernaculum and dilation of the internal inguinal ring was not possible. During a parainguinal approach to the abdomen, an enlarged cystic testicle was discovered. Histopathologic diagnosis was cystic rete testis. This case report stresses the importance of preoperative ultrasonographic assessment of cryptorchid testicles to decrease surgical time.     

Expression of lactoferrin in the boar epididymis: effects of reduced estrogen

Lactoferrin is regulated by estrogen in the female reproductive tract and evidence in immature mice suggests that it may be estrogen regulated in males as well. The estrogen regulation of lactoferrin in the epididymis of the boar, a high estrogen-producing male, is unknown. This study was designed to test the hypothesis that lactoferrin expression in the boar epididymis is regulated by estrogen. Twenty-one littermate pairs of boars were treated with vehicle or Letrozole, an aromatase inhibitor, from 1 week of age until castration at 2 through 8 months. Epididymal tissue was collected at castration and fixed for immunolocalization of lactoferrin. Epididymal and testicular tissues were also collected from five mature boars (1-2.5 years) and fixed for immunocytochemistry (ICC). Lactoferrin was localized in the principal cell cytoplasm of the caput, corpus and cauda of developing boars but only in the corpus and cauda of mature boars. Basal cells were negative for lactoferrin. Sperm in the corpus and cauda was also positive for lactoferrin. The efferent ducts and testes were negative for lactoferrin. Intensity of lactoferrin immunostaining increased with age in the corpus and cauda regardless of treatment. Reduced endogenous estrogen in the epididymis during development did not affect the intensity of immunostaining between control and Letrozole-treated animals. Lactoferrin expression in the epididymis of the developing boar does not appear to be regulated by estrogen.     

Subtotal colectomy and ileocolonic anastomosis in a Vietnamese pot-bellied pig with idiopathic megacolon

A 7-month-old sexually intact female Vietnamese pot-bellied pig was evaluated because of constipation. On abdominal palpation, a hard tubular structure was palpated in the middle of the abdomen. Abdominal radiography revealed loops of intestine that were markedly distended with ingesta, consistent with obstructive intestinal disease. On exploratory celiotomy, a massively distended cecum and spiral colon were found. A subtotal colectomy, with a side-to-side ileocolonic anastomosis, was performed. The cause of the megacolon was not discovered. The pig did well following surgery and eventually defecated normally following an initial period of diarrhea. To our knowledge, this is the first report of therapeutic removal of a substantial portion of the large intestine in swine. Our decisions concerning the pig of this report were based largely on our knowledge of megacolon in cats. The outcome for this pig indicates that subtotal colectomy along with removal of the cecum and ileocecal valve can be used to successfully treat idiopathic megacolon in Vietnamese pot-bellied pigs.     

COMPARATIVE STUDY OF SCROTAL AND PRESCROTAL CASTRATION IN PET RABBITS (ORYCTOLAGUS CUNICULUS)

Castration of rabbits can be achieved with several surgical techniques. The choice of the technique currently depends on surgeon preference since objective comparison between techniques is lacking. The aim of the current study was to compare the scrotal and prescrotal approaches in pet rabbits. The surgery and anesthesia duration, the postoperative appetite and feces production, and the postoperative complications were compared. Thirteen rabbits were randomly assigned to the scrotal or prescrotal castration groups. Appetite, fecal output, surgical incisions, and scrotums were evaluated at 8 hourse, 24 hours, 32 hours, and 7 days after surgery. Scrotal edema at 8, 24, and 32 hours and anesthesia duration were significantly higher in the scrotal group compared to the prescrotal group (P = 0.008, P = 0.013, P = 0.021, and P = 0.034, respectively). A nonsignificant tendency toward a higher rate of licking and mutilation behaviors was observed in the scrotal group 24 hours postsurgery. No other complications were observed in either group. All rabbits quickly recovered a normal appetite and fecal output, and all surgical incisions healed without issue. Although the prescrotal technique was associated with less complications, both techniques were considered safe options for rabbits in this study.