Topic:Castration
Castration in horses is a surgical procedure that involves the removal of the testicles, primarily performed to reduce aggressive behavior and prevent breeding. This operation, typically conducted on young male horses, or colts, can be done using various techniques, including open, closed, or laparoscopic methods. The procedure is generally carried out under anesthesia and requires post-operative care to minimize complications such as infection, swelling, or hemorrhage. Castration can influence a horse's physiology and behavior, often resulting in calmer temperaments and easier handling. This page offers a collection of peer-reviewed research studies and scholarly articles that explore the methodologies, physiological impacts, and behavioral changes associated with castration in equines.
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...
Biotransformation of 1-dehydrotestosterone in the equine male castrate: identification of the neutral unconjugated and glucuronic acid conjugated metabolites in horse urine. The in vivo biotransformation of (1,2(n)-3H)1-dehydrotestosterone was studied in three equine male castrates and a number of neutral metabolites were identified in the urinary unconjugated and glucuronic acid conjugate fractions by gas chromatography/mass spectrometry. The metabolites were extracted from aliquots of the 0-24 h urine samples by Amberlite XAD-2 and separated into combined unconjugated plus glucuronic acid conjugated and sulphoconjugated fractions by Sephadex LH-20 column chromatography. After enzymatic hydrolysis of the glucuronides, the crude neutral unconjugated steroids plus ...
Surgical repair of urethral transection in a horse. A recently castrated horse was examined because of preputial and ventral abdominal swelling, prolapse of the preputial fold, and serosanguinous fluid dripping from the external urethral orifice. After a poor response to initial medical management, a urethral laceration was found during exploratory surgery. Half of the ventral portion of the corpus cavernosum penis had been transected. Primary closure was followed by healing without complications.
Ruptured inguinal hernia in new-born colt foals: a review of 14 cases. Over a six year period, 14 new-born colt foals were treated surgically because of ruptured inguinal hernia. In all cases, the prolapsed intestines, which were jejunal loops, were situated subcutaneously and protruded through a rent in the parietal vaginal tunic at the level of the inguinal canal. After herniorrhaphy and unilateral castration, the prolapsed loops were replaced into the abdomen, and the superficial inguinal ring closed. Seven foals survived.
Surgical treatment of acquired inguinal hernia in the horse: a review of 51 cases. During a seven year period, 51 cases of acquired inguinal herniation in 50 stallions were treated surgically. In 25 cases the herniated loop was ileal, in the other 26 it was jejunal. In cases of strangulation, the vaginal ring was enlarged by incising the peritoneum and transverse fascia. Closure of the superficial inguinal ring was advisable to prevent the hernia recurring. In all cases unilateral castration was performed. Laparotomy was carried out in 33 cases; 22 required intestinal resection and in four cases a bypass was made. Follow-up at least six months postoperatively indicated that ...
Septic periorchitis in a horse. A 2-month-old Standard-bred colt with signs of abdominal pain and large scrotum was found to have septic periorchitis involving the right testis. Surgical exploration of the abdomen and scrotum was performed; the colt was then castrated. Actinobacillus equuli was isolated from specimens obtained at surgery. The colt was treated with broad-spectrum antibiotics and flunixin meglumine after surgery, and fully recovered. The clinical signs of periorchitis in the colt were similar to an inguinal/scrotal hernia.
Effects of castration on peritoneal fluid in the horse. Twenty-four clinically normal horses were castrated by routine methods. Peritoneal fluid was collected prior to castration and at 1, 3, 5, and 7 days postcastration. Peritoneal fluid was collected on days 9 and 11 if nucleated cell (NC) counts were still markedly elevated on day 7. Peritonitis, defined as NC counts greater than 10,000/microliters, was evident in 15 horses following castration. Mean NC counts peaked on day 5 but were less than 10,000/microliters for 74% of the horses by day 7, and 90% of the horses by day 9. One horse had a NC count greater than 60,000/microliters on day 11 whe...
Botulism as a sequel to open castration in a horse. Clostridium botulinum and type-B C botulinum toxin were isolated from a necrotic wound that developed subsequent to castration in a 2-year-old Thoroughbred gelding. The horse had clinical signs of botulism and was successfully treated with wound debridement, C botulinum type-B antitoxin, potassium penicillin, and supportive care.
Surgical treatment of priapism in a stallion. Priapism occurred in a stallion after the administration of acetylpromazine. When conservative measures failed, the corpus cavernosum penis (CCP) was drained and irrigated, and a vascular shunt between the erectile bodies was created. Subsidence of erection resulted, but subsequently, the stallion was unable to retract or erect the penis. The stallion was castrated and the penis was surgically retracted into the sheath.
Imipramine-induced erection, masturbation, and ejaculation in male horses. Imipramine hydrochloride was administered to five male horses (400-500 kg b.wt.): one experienced young stallion, two mature normal breeding stallions, one 5-year-old stallion with erection and ejaculatory dysfunction, and one long-term castrated male horse. Oral imipramine treatment (100 to 600 mg, twice daily) led to frequent erection and masturbation while at rest in the stall in a nonsexual context. Intravenous imipramine treatment over a range of doses (50 to 1000 mg) similarly induced erection and masturbation in all animals. Erection typically occurred within 10 minutes after injection,...
Acquired incarcerated inguinal hernia: a review of 13 horses. The case records of 13 horses with acquired incarcerated inguinal hernia in January-August 1983, were reviewed. Nine cases were in stallions. The remaining four involved eventration 5-48 hours following castration. Ages ranged from 1-17 years. Horses showed a variable degree of colic. Bowel was felt to pass through the internal inguinal ring on rectal examination in most cases. The physical features of the scrotum varied considerably. Resection of ischemic jejunum and/or ileum was necessary in three horses. Two horses were euthanized at surgery (one with bilateral ischemic jejunum, one with bo...
A clinical trial of three anaesthetic regimens for the castration of ponies. After premedication with intravenous xylazine 30 ponies were anaesthetised for castration under field conditions with intravenous ketamine, thiopentone or methohexitone. The duration of anaesthesia was adequate for surgery and the times taken to stand were similar in each group. The recovery of the ponies after ketamine was quieter than after either of the barbiturates and this may be an advantage when skilled assistance is lacking. However, all the anaesthetics appeared to be suitable for performing minor surgery in the field.
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.
A modified parainguinal approach for cryptorchidectomy in horses. An evaluation in 107 horses. A modified parainguinal approach was used to castrate 119 abdominal cryptorchid horses. The operative time ranged from 10 to 30 minutes. Follow-up information was obtained for 107 horses. Swelling, more severe than that expected in routine castrations, was reported in six horses. An incisional abscess had to be drained in one horse and one horse died of unexplained causes 3 days after the surgery.
Circadian, circhoral and seasonal variation in patterns of gonadotrophin secretion in geldings. Blood samples were obtained from 5 mixed-breed, long-term castrated geldings during five 24-h periods between May 1984 and April 1985. Blood samples were collected, beginning at 09:00 h, at 15-min intervals for 8 h and hourly for the remaining 16 h. Plasma concentrations of LH and FSH were determined by RIA. Seasonal changes in hormone concentrations and frequency and amplitude of secretory pulses were evaluated. No diurnal variation in either LH or FSH secretion was observed: however, marked circhoral fluctuations in LH and FSH secretion were noted. Mean LH and FSH concentrations in these lon...
Development of a gas chromatographic-mass spectrometric method using multiple analytes for the confirmatory analysis of anabolic steroid residues in horse urine. II. Detection of administration of 19-nortestosterone phenylpropionate to equine male castrates and fillies. Esters of 19-nortestosterone form an important group of anabolic preparations used in veterinary practice. Based upon results from detailed metabolic studies for 19-nortestosterone in the horse, a method to confirm the administration of anabolic preparations of this steroid to castrated male horses and fillies is described; the method is based upon the use of multiple analytes. Following administration of the anabolic preparations, solid-phase extraction of urinary conjugates and the separation of the conjugate groups prior to hydrolysis allow for the determination of specific metabolites conj...
The biotransformation and urinary excretion of dexamethasone in equine male castrates. The pro-drugs of dexamethasone, a potent glucocorticoid, are frequently used as anti-inflammatory steroids in equine veterinary practice. In the present study the biotransformation and urinary excretion of tritium labelled dexamethasone were investigated in cross-bred castrated male horses after therapeutic doses. Between 40-50% of the administered radioactivity was excreted in the urine within 24 h; a further 10% being excreted over the next 3 days. The urinary radioactivity was largely excreted in the unconjugated steroid fraction. In the first 24 h urine sample, 26-36% of the total dose was...
Comparison of the measurement of plasma testosterone and plasma oestrogens for the diagnosis of cryptorchidism in the horse. The results of performing 1720 blood tests for equine cryptorchidism are described. Using the paired sample human chorionic gonadotrophin (hCG) stimulation test and measuring testosterone, 6.7 per cent of tests did not give a clear result. If only the testosterone concentration in the pre-hCG blood sample was used, this percentage rose to 14 per cent. The paired sample hCG stimulation test was 94.6 per cent accurate. A comparison was made between the paired hCG stimulation test and the measurement of conjugated oestrogen in a single sample. The latter did not give as many doubtfuls but gave fa...
Development of a gas chromatographic-mass spectrometric method using multiple analytes for the confirmatory analysis of anabolic steroids in horse urine. I. Detection of testosterone phenylpropionate administrations to equine male castrates. A gas chromatographic-mass spectrometric (GC-MS) method using three analytes to detect and confirm the administration to equine male castrates of veterinary pro-drugs based upon esters of testosterone is described. The method involves extraction of steroid conjugates from horse urine by C18-bonded cartridges and fractionation into glucuronic acid and sulpho-conjugates by Sephadex LH-20 column chromatography. After deconjugation, the free neutral steroids were partially purified by thin-layer chromatography and following derivatization (methyloxime-trimethylsilyl ether) were analysed by capilla...
Behaviour of the false rig: causes and treatments. The false rig is a castrated horse which shows masculine behaviour of one sort or another. The behaviour patterns reported to the author by owners of such animals and the possible causes are discussed here. Some such horses can show all the behaviour patterns of the entire, including erection and intromission. Evidence is presented that the behaviour is not hormonally induced or hormone dependent. The thesis is put forward that the behaviour shown is part of the normal social interaction between horses and possible treatments are discussed in the light of this possibility.
Impaired estrogen production by Leydig cells of the naturally retained testis in unilaterally cryptorchid boars and stallions. Estrogen production in vitro was compared for Leydig cells from cryptorchid and scrotal testes in boars and stallions. Animals with natural and experimental cryptorchidism were used. Purified Leydig cells were prepared from testes of mature animals by collagenase treatment and Percoll density gradients. After incubation for 3 hours (1 X 10(6) cells), estrone sulfate and estrone in the media were measured by direct radioimmunoassay. Androstenedione and testosterone in media extracts also were determined. Cells from the abdominal testis of unilateral cryptorchid boars and stallions showed impair...
Seasonal variation in the feedback of sex steroid hormones on serum LH concentrations in the male horse. The possibility of seasonal variation in the feedback effect of testosterone or oestradiol was investigated by giving replacement treatment to geldings for 2-3 weeks during breeding and non-breeding seasons. In the non-breeding season, testosterone suppressed LH values (mean +/- s.e.m., ng/ml) in all geldings (before treatment, 7.5 +/- 2.3; final treatment week, 1.8 +/- 0.2; P less than 0.05), whereas early in the breeding season, testosterone caused a prolonged rise in LH (before, 6.8 +/- 2.3; final week, 18.9 +/- 6.4; P less than 0.05). In all testosterone experiments, LH returned to pretrea...
Animal welfare considerations – pastoral animals. Modern pastoral farming has radically transformed the niche where agricultural animals live. Recent trends in husbandry tend to give as much emphasis to economic profit and human convenience, as do a concern for the farmed species. Most of the traditional ways of handling sheep, cattle, goats, horses and pigs, like castration, ear tagging, tail-docking or horse breaking, have been accepted by the public with little concern. Inevitably, as renewed public interest focuses on intensive farming, some questions are directed towards extensive pastoral farming practices, particularly in newly-farmed ...
Complications from a testicular prosthesis in a stallion. A testicular prosthesis was removed from the scrotum of a 3-year-old Quarter Horse stallion. The prosthesis had been placed in the left side of the scrotum 10 months earlier, after an unsuccessful attempt to reposition the retained left testis. Because of a persistent draining fistula on the scrotum, first noted 5 months after placement of the prosthesis, surgery was performed to remove the prosthesis. At surgery, the left testis was found in a fibrous mass surrounding the prosthesis. The left testis had descended after placement of the prosthesis, and its involvement in the fibrous tissue sur...
Paraphimosis in seven debilitated horses. This paper reports seven cases of penile paraphimosis which occurred in both entire and castrated horses in association with general debility. Two cases were discharged after treatment while still suffering from partial paralysis; one was discharged at the owner's request with complete paralysis; three were destroyed and one died during treatment. Identified causes of debility were malnutrition, severe parasitism, glucose malabsorption and salmonellosis.
Effect of prepubertal versus postpubertal castration on sexual and aggressive behavior in male horses. Males horses castrated prepubertally occasionally display stallion-like sexual and aggressive behavior as adults. A retrospective survey of 140 horse owners was undertaken to compare the effectiveness of prepubertal versus postpubertal castration on objectionable sexual and aggressive behavior. Of 94 geldings that had been castrated prepubertally (before 2 years of age), 20% to 30% displayed stallion-like sexual behavior and aggression toward horses, and 5% were aggressive toward people in a stallion-like manner. This occurrence of problem behavior was not significantly different from the occu...