Use of a preputial circumferential mucosal flap for hypospadias management in a Boston terrier

An eight-week-old male Boston terrier presented for penile desiccation and urine pooling in the prepuce due to congenital hypospadias. An advancement flap was created from the dorsal mucosa of the incompletely formed prepuce and sutured circumferentially to construct a longer distal preputial mucosa. V- to Y-plasty of the ventral abdominal skin was utilised to create the preputial skin overlying the mucosal flap. Urethrostomy and partial penile amputation were also performed. Following surgery, the clinical signs of penile desiccation and preputial urine pooling resolved and acceptable cosmetic appearance was achieved. This technique may be considered for glandular or penile hypospadias or following resection of the ventral aspect of the distal prepuce when inadequate tissue is present for a simple two-layer closure of the preputial mucosa and skin.     

Priapism in a stallion with generalized malignant melanoma

A Thoroughbred stallion developed priapism that was unresponsive to medical treatment and lavage of the corpus cavernosum penis with heparinized 0.9% NaCl solution. Three weeks after onset of priapism, the penis was firm and noncompliant, and penile pain sensation and ability to retract the penis were lost. Ultrasonography confirmed thrombosis of the corpus cavernosum penis. The stallion was euthanatized because of poor prognosis for return to breeding soundness. Necropsy revealed enlargement of numerous lymph nodes. The dorsal penile nerves were demyelinated distal to the crura of the penis. A diagnosis of generalized malignant melanoma was made; however, neither metastasis to the vertebral canal nor compression of spinal nerve roots as they exited the vertebral foramen was found. Priapism is a persistent erection without sexual arousal and is initially unassociated with penile paralysis, but if prolonged, leads to irreversible venous occlusion where collecting veins join the cavernous spaces. Damage to the dorsal penile nerves may explain the long-term penile paralysis and loss of sensation that accompanied priapism in this stallion. Priapism unassociated with the use of phenothiazine-derivative tranquilizers is uncommon in horses.     

Penile amputation and scrotal urethrostomy in 18 dogs

The objective of this study was to report the signalment, indications for surgery, postoperative complications and outcome in dogs undergoing penile amputation and scrotal urethrostomy. Medical records of three surgical referral facilities were reviewed for dogs undergoing penile amputation and scrotal urethrostomy between January 2003 and July 2010. Data collected included signalment, presenting signs, indication for penile amputation, surgical technique, postoperative complications and long-term outcome. Eighteen dogs were included in the study. Indications for surgery were treatment of neoplasia (n=6), external or unknown penile trauma (n=4), penile trauma or necrosis associated with urethral obstruction with calculi (n=3), priapism (n=4) and balanoposthitis (n=1). All dogs suffered mild postoperative haemorrhage (posturination and/or spontaneous) from the urethrostomy stoma for up to 21 days (mean 5.5 days). Four dogs had minor complications recorded at suture removal (minor dehiscence (n=1), mild bruising and swelling around the urethrostomy site and mild haemorrhage at suture removal (n=2), and granulation at the edge of stoma (n=1)). One dog had a major complication (wound dehiscence and subsequent stricture of the stoma). Long-term outcome was excellent in all dogs with non-neoplastic disease. Local tumour recurrence and/or metastatic disease occurred within five to 12 months of surgery in two dogs undergoing penile amputation for the treatment of neoplasia. Both dogs were euthanased.     

Arterial supply of the penis in the New Zealand rabbit (Oryctolagus cuniculus L.)

In the present study, the distributional pattern of the penile artery and the vessels joining the blood supply of the penis were investigated in the New Zealand rabbit. Eight adult rabbits were used in the study. In order to exhibit the vascular network by dissection, latex was injected via the abdominal aorta. The main vessel which supplies blood to the penis, the penile artery, is a branch of the internal pudendal artery. It divides into two branches which form the deep and dorsal penile arteries at the level of the ischiadic arch. The deep penile artery penetrates the tunica albuginea, and forms the arterial network of corpus cavernosum penis. On the other hand, the dorsal penile artery gives off three small branches for the subischiocavernosus muscle and at the level of the attachment of this muscle sends two small branches for the preputium. The course of both arteries follows the dorsolateral surface of the penis to the glans and ends in an anastomosis. Hence, a caudal branch of the prostatic artery which originates from the umbilical artery joins the blood supply of the penis in the rabbit. After vascularizing the prostate complex, it ends by entering the corpus spongiosus penis at the dorsolateral surface at the level of the ischiadic arch.     

Penile hematoma in bulls: 60 cases (1979-1990).

Sixty bulls with penile hematomas were examined from 1979 through 1990. Thirty-eight bulls underwent surgical correction, 17 bulls were managed by medical treatment, and 5 bulls were not treated. Hereford and Polled Hereford breeds represented the majority (n = 37, 62%) of the bulls, with 10 other breeds representing the remainder (n = 21, 35%) in this study; breed was not reported in 2 bulls. Follow-up information was obtained from owners (40/60) through conversation on the success or failure of treatment, interval of sexual rest, duration of breeding soundness, and final outcome of the bull. Surgical correction was successful in 19 (70%) of 27 cases; medical treatment was successful in 6 (46%) of 13 cases. Of the 8 bulls that had penile hematomas with swelling measuring > 20 cm in width, 6 were successfully treated surgically, compared with 1 of 3 successfully treated medically. Of the bulls with penile hematomas having a swelling measuring < or = 20 cm in width, 7 of 9 were successfully treated surgically, compared with 4 of 5 successfully treated medically. Duration of the penile hematoma had little effect on the success of surgical correction. Of the bulls allowed sexual rest for > 2 months after treatment was initiated, 6 (25%) of 24 had a recurrence of penile hematoma. Four (40%) of 10 bulls allowed sexual rest for < or = 2 months had a recurrence of penile hematoma.     

Arterial supply of the penis in agoutis (Dasyprocta prymnolpha, Wagler, 1831)

The arterial vascularization of agoutis’ penis (Dasyprocta prymnolopha) were analysed using ten male adults from ‘Núcleo de Estudos e Preservação de Animais Silvestres da Universidade Federal do Piauí’ (FUFPI/IBAMA n° 02/99). Among the total number of specimens, six animals had natural death and were members of the research collection of the Laboratory of Anatomy, and four were killed after anaesthesia. Stained bi‐centrifugated‐Cis‐I‐4 latex was injected in arterial vessels responsible for penis vascularization throughout the abdominal portion of aorta. The samples were fixed in 10% formaldehyde solution and arteries were dissected. The penile artery is originated as a branch of internal pudendal artery. At the level of ischiatic arch, the penile artery project two branches, the penile dorsal and the deep arteries; those arteries irrigates the penile dorsal surface and the corpus cavernosum penis. The penile dorsal arteries have an independent course up to the glans penis. Based on the conditions of this work a remarkable similarity regarding the distribution of vessels destined to the agouti penis when compared to other domestic, wild and lagomorph rodents as rabbits.     

Causes of copulatory failure in beef bulls

A cow in full standing estrus is required to assess a bull's ability to copulate. Insufficient libido is not involved if the bull sniffs the cow's vulva and attempts to mount. Blood or pus exiting the penis or prepuce indicates penile or preputial lacerations or other lesions. Rear foot or stifle lesions, seminal vesiculitis, traumatic reticulitis or lumbar spinal injuries may prevent the bull from mounting. Preputial stenosis, penile adhesions, desensitization, hematomas or deviations, peripreputial abscess, cavernosal shunts, insufficient penile length and occlusions of the cavernosal canals may prevent intromission after mounting.     

Penile Amputation and Sheath Ablation in the Horse

OBJECTIVE: To report a surgical technique for penile amputation and sheath ablation in horses. Study Design-Retrospective study. Animals or Sample Population-Twenty-five adult geldings of various breeds with conditions requiring penile amputation and sheath ablation. METHODS: The medical records of horses that had penile amputation and sheath ablation were reviewed. Briefly, the technique involved en bloc resection of the skin and subcutaneous tissues of the inner and outer lamina of the prepuce and penile shaft. Resection of the penile shaft, proximal to diseased segments, and spatulation of the urethral mucosa was followed by fixation of the penis to the ventral abdomen and closure of the peripreputial skin over the ventral aspect of the penis and creation of a new mucocutaneous junction at the urethral orifice. RESULTS: Mild to moderate postoperative hemorrhage occurred in all horses. Partial dehiscence of the mucocutaneous junction occurred in 8 horses; all healed by second intention. Postoperative pain lasting 24 to 48 hours occurred in 7 horses; 1 required epidural analgesia for pain relief. Long-term follow-up was available for 8 horses; none had any long-term complications. CLINICAL RELEVANCE: Partial amputation of the penis with pexy to the ventral abdomen and revision of the peripreputial skin can be used as an alternative to en bloc resection and penile retroversion for lesions involving the free part of the penis and the prepuce. It requires smaller incisions and results in less alteration to the normal appearance of the external genitalia than retroversion techniques, while still allowing the surgeon to remove extensive portions of the penis and extirpate the regional lymph nodes.     

Alternative method to facilitate resolution of paraphimosis after penile trauma in the horse

Inflammation associated with traumatic injury to the penis is characterised by pain, heat and oedema. Ensuing penile swelling interferes with retraction of the penis into the prepuce, resulting in paraphimosis. This report describes the use of a 5 l capacity pressure infusion bag to reduce penile oedema in three horses. This technique provided complete resolution of oedema and associated paraphimosis in approximately 1 h. The use of the bag, along with an abdominoinguinal bandage, a plastic funnel suspensory device, or a penile repulsion device (Probang) to avoid recurrence, offers a novel treatment that may be performed with the horse sedated.     

Surgery and radiation therapy for extramedullary plasmacytoma of the penile mucosa in a dog

A 10-year-old neutered male Italian greyhound dog was presented because it had a penile plasmacytoma. Surgery followed by radiation therapy resulted in local control and survival for 1688 days. This is the first report of surgery and definitive radiation therapy for curative intent therapy of extramedullary penile plasmacytoma in a dog.     

Subtotal penile amputation and preputial urethrostomy in a dog

CASE DESCRIPTION: A 6-year-old castrated male Shih Tzu was evaluated because of intermittent bleeding during urination. CLINICAL FINDINGS: Necrosis of the cranial portion of the penile shaft extended distally from the preputial fornix. Penile necrosis secondary to strangulation from paraphimosis was diagnosed. TREATMENT AND OUTCOME: A midline preputiotomy incision was used to expose the penile shaft; amputation was performed caudal to the preputial fornix. The terminal portion of the urethra was anastomosed to the preputial mucosa, which allowed the dog to urinate through the preputial orifice. CLINICAL RELEVANCE: Unlike the more conventional urethrostomy procedures performed in dogs, preputial urethrostomy eliminates the potential for local skin irritation during urination. Preputial urethrostomy is also easier to perform in those dogs in which penile amputation is required adjacent to the preputial fornix. A release incision cranial to the prepuce can be used to facilitate caudal displacement of the preputial mucosa, which facilitates urethral anastomosis to this structure. A midline preputiotomy incision provided excellent exposure of the penile shaft for this surgical procedure.     

Devil's claw (Harpagophytum procumbens) in a Brahman's preputial sheath: a case report from Botswana

Failure of penile protrusion during attempted service of a cow on heat was investigated in a 3-year-old Brahman bull at Kwakwadi cattle-post in the Kgalahadi sandveld, Kweneng District, Botswana. The investigation revealed that penile protrusion was obstructed by a devil's claw (grapple thorn), a dry fruit of the plant Harpagophytum procumbens, which had lodged in the cavum preputiale. The thorn, which was removed almost completely manually with minimal tissue dissection, had also caused minor lacerations and puncture wounds on the lamina interna pars parietalis. The wounds healed well following treatment with antiseptics and antibiotics and subsequently the bull regained full penile protrusion and served the cows well. This report describes the first case of lodgement of a devil's claw fruit in, and its extraction from, the cavum preputiale of a Brahman.     

Contemporary use of acepromazine in the anaesthetic management of male horses and ponies: a retrospective study and opinion poll

Reason for performing study: Current use of acepromazine in the anaesthetic management of male horses and ponies and associated risks are largely unknown. Objectives: To explore anaesthetic acepromazine use and related adverse effects in the male horse. Methods: Of 8533 anaesthetised horses and ponies medical records of male animals treated perianaesthetically with acepromazine were reviewed. Demographic data, time and dose of acepromazine administration, co‐administered drugs, quality of induction and recovery from anaesthesia, arterial blood pressures, and occurrence of penile dysfunction were recorded. Practising ACVA and ECVAA diplomates were polled on the use of acepromazine and its effects on blood pressure and penile dysfunction in the equine. Results: Of all animals, 12% females and 11% males (n = 575 including 42% stallions) received perianaesthetic acepromazine, predominantly for premedication. Anaesthetic induction was smooth in 566 animals. Lowest mean arterial pressures averaged 65 ± 9 mmHg. Recovery was good or very good in 70% of all animals and 74% stood after 1–2 attempts. In 14 horses (2.4%; 7 stallions, 7 geldings), penile prolapse occurred for 0.5–4 h and in one stallion (0.2%) for >12 but <18 h post recovery. Most surveyed anaesthesiologists use acepromazine in stallions (occasionally 63%; frequently 17%) but more frequently in geldings (occasionally 34%; frequently 59%) and mares (occasionally 38%; frequently 59%), primarily for premedication with other sedatives and analgesics. Persistent intraoperative hypotension was not frequently reported. Only 5% of surveyed anaesthesiologists recall penile prolapse post acepromazine administration lasting for >12 h and only one recalls 3 cases of irreversible penile prolapse in 20 years of anaesthesia practice. Conclusions and potential relevance: The extremely low risk of permanent penile dysfunction (≤1 in 10,000 cases) does not justify more restricted use of acepromazine in the intact male vs. geldings and mares.     

Penile and preputial tumours in the horse: literature review and proposal of a standardised approach

Penile and preputial tumours are not uncommon in the horse, but can cause discomfort and lead to serious complications. Several types of tumour of the male external genitalia have been described. The most common type is the squamous cell carcinoma (SCC), which is found mainly in older horses. Reports of a breed predilection for penile tumour formation are equivocal, but castration, coat colour, poor hygiene and various infectious agents have all been suggested to predispose to the development of some types of tumour (e.g. SCC, papilloma and melanoma). Careful assessment of the primary tumour is an important first step in the design of an optimal treatment protocol. Invasiveness, differentiation grade, tumour size and presence of metastases are all relevant to the decision to pursue additional diagnostic procedures or specific treatment options. To date, no standard protocol has been reported for the approach to penile tumours in the horse and treatments range from minimally invasive therapies (e.g. topical use of 5-fluorouracil) to radical surgical interventions (e.g. en bloc penile and preputial resection with penile retroversion). Completeness of removal of the neoplasm and therefore risk of recurrence is highly dependent on the type of therapy chosen. However, the size and histopathological features of the primary tumour are also important factors with respect to the likelihood of recurrence. This review describes the most common penile and preputial neoplasms in the horse, and outlines a standard protocol aimed at arriving at a specific diagnosis and tailoring the therapeutic approach accordingly.     

Penile Extramedullary Plasmacytoma in a Dog

Penile tumours are rare in dogs. Reported herein is a case of a penile extramedullary plasmacytoma (EMP) in a 5‐year‐old male cocker spaniel that was brought to a local hospital for an evaluation of a penile mass. The mass was approximately 1.3 cm in diameter at the time of presentation. In fine needle aspiration and histopathological examinations, the neoplastic cells showed eccentric round nuclei, a moderate amount of basophilic cytoplasm, and a peri‐nuclear clear zone, consistent with plasma cell morphology. There was nuclear pleomorphism with mononuclear giant cells and occasional bi‐nucleation. Round cells on the periphery of the mass demonstrated plasmacytic differentiation. Immunohistochemically, the neoplastic cells stained positive for MUM1 and light lambda chain. Based on the cytological and pathological observations, a diagnosis of penile EMP was established.     

Equine penile squamous cell carcinomas are associated with the presence of equine papillomavirus type 2 DNA sequences

Forty cases of equine penile disease were screened with polymerase chain reaction for the presence of papillomaviral DNA. Cases consisted of 20 squamous cell carcinomas (average age of horse, 23.9 years) and 20 non-squamous cell carcinoma diseases (average age of horse, 13.3 years). All horses but one originated from the Northeastern United States. Breeds were not recorded. As based on MY09/MY11 consensus primers, DNA sequences from equine papillomavirus type 2 were amplified from 9 of 20 horses (45%) with penile squamous cell carcinoma and only 1 of 20 horses (5%) with non-squamous cell carcinoma penile disease. Equine papillomavirus type 2 DNA was the only papillomaviral DNA amplified from any of the 40 horses. Tissues from the 10 horses in which papillomaviral DNA was detected by polymerase chain reaction were also screened with in situ hybridization and immunohistochemistry. The presence of papillomavirus was demonstrated in a subset of these by in situ hybridization (6 of 10) and immunohistochemistry (1 of 10). This report describes a possible association between equine penile squamous cell carcinomas and equine papillomavirus type 2. This study is also the first report of equine papillomavirus type 2 infection in North American horses.     

Idiopathic chronic penile protrusion in the dog: a report of six cases

Idiopathic chronic penile protrusion was diagnosed in six dogs during a seven year period. All cases were treated surgically by using cranial advancement of the prepuce. The surgical technique was successful in four dogs, while the remaining two developed recurrence. In one of the latter cases, partial penile amputation was performed to correct the recurrent protrusion. Five dogs were available for follow-up clinical examination and all were found to be normal.     

Anatomical Stages of Penile Erection in the Agouti (Dasyprocta leporina) Induced by Electro-Ejaculation

The reproductive system of the male agouti is not well documented. This study describes the specific anatomical features of the free part of the penis occurring during penile erection in the agouti. Electro-ejaculation was used to induce erection in three male agoutis that had previously produced offspring. Results proved that there were four stages in the erection process. Stage 1 involved protrusion of the penis from the preputial orifice. The lateral penile cartilages were then spread (stage 2). During stage 3, there was the blooming of the head of the glans penis (penile flower) and eversion of the intromittent sac. The protrusion of the keratinaceous styles and ejaculation occurred during stage 4. This information could assist in semen collection for use in reproductive techniques for the agouti such as artificial insemination.     

The Capillary Circulation in the Penile Skin of the Dog

The microcirculation of the penile skin of the dog is described. This study is based on the examination of the penile skin vasculature of 14 adult dogs in which injection cast preparations of the capillary systems had been made. The capillary organization was examined with the aid of a scanning electron microscope. The organization of the capillary system and associated microregulatory vessels are presented as a model for further investigation of micro-circulatory anatomy and physiology.     

EcPV2 DNA in equine genital squamous cell carcinomas and normal genital mucosa

Squamous cell carcinoma (SCC) represents the most common genital malignant tumor in horses. Similar to humans, papillomaviruses (PVs) have been proposed as etiological agents and recently Equine papillomavirus type 2 (EcPV2) has been identified in a subset of genital SCCs. The goals of this study were (1) to determine the prevalence of EcPV2 DNA in tissue samples from equine genital SCCs, penile intraepithelial neoplasia (PIN) and penile papillomas, using EcPV2-specific PCR, (2) to examine the prevalence of latent EcPV2 infection in healthy genital mucosa and (3) to determine genetic variability within EcPV2 and to disentangle phylogenetic relationships of EcPV2 among PVs. EcPV2 DNA was detected in all but one penile SCC (15/16), in all PIN lesions (8/8) and penile papillomas (4/4). Additionally, EcPV2 DNA was demonstrated in one of two metastasized lymph nodes, one contact metastasis in the mouth, two vaginal and one anal lesion. In healthy horses, EcPV2 DNA was detected in 10% (4/39) of penile swabs but in none of vulvovaginal swabs (0/20). This study confirms the presence of EcPV2 DNA in equine genital SCCs and shows its involvement in anal lesions, a lymph node and contact metastases. Latent EcPV2 presence was also shown in normal male genital mucosa. We found that different EcPV2 variants cocirculate among horses and that EcPV2 is related to the Delta+Zeta PVs and is only a very distant relative of high-risk human PVs causing genital cancer. Thus, similar viral tropism and similar malignant outcome of the infection do not imply close evolutionary relationship.