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.
Comparison of xylazine and detomidine in combination with midazolam/ketamine for field castration in Quarter Horses. The ideal field anaesthetic protocol for castration will offer an adequate duration and depth of anaesthesia using a single injection without compromising safety or recovery quality. Objective: The objective of this study was to compare intravenous (IV) xylazine and detomidine as sedatives in combination with midazolam and ketamine for induction of anaesthesia in horses undergoing field castration. Methods: Randomised, blinded, clinical study. Methods: Fifty-seven male Quarter Horses were randomly assigned to receive xylazine (group X) (1.1 mg/kg bwt) or detomidine (group D) (0.03 mg/kg bwt)...
Evaluation of three ligatures in simulated equine open castration. To compare three surgical knots for preventing leakage from the vascular bundle during ligation in simulated equine open castrations. Methods: Randomized, case-control, in vitro study. Methods: Testes (N = 60) collected from 30 horses. Methods: Testes were collected from 30 horses and randomly assigned to one of three groups: group G (friction, giant knot), group T (modified transfixing knot), or group S (sliding, strangle knot; n = 20/group). The assigned knot was used to ligate the vascular bundle during open castration. The length of suture material used and the leak pressure of the testicu...
Chitosan-based agent use for hemostasis after cryptorchidectomy in a horse. To document marked hemorrhage as a complication of inguinal cryptorchidectomy and its successful treatment with a novel chitosan-based hemostatic agent. Methods: Case report. Methods: One healthy 5-year old quarter horse cryptorchid. Methods: The horse was presented for routine unilateral cryptorchidectomy after prior hemicastration. An inguinal approach was made to the abdomen, and the right external pudendal artery was lacerated at the level of the internal inguinal ring, requiring multiple anesthetic events over a 2-week period in attempts to control hemorrhage. A chitosan-based hemostatic ...
Pharmacopuncture Analgesia Using Flunixin Meglumine Injection into the Acupoint GV1 (Ho Hai) After Elective Castration in Horses. The study evaluated the effect of a 1/10 dose of flunixin meglumine administered into the governing vessel 1 (GV1) acupoint in horses that underwent castration. Twenty animals received 0.02 mg/kg detomidine intravenously, followed by 2.2 mg/kg ketamine and 0.1 mg/kg diazepam by the same route, and also a local anesthesia with 30 mL lidocaine. As postoperative analgesia, the animals received 1.1 mg/kg flunixin meglumine IV (FIV) or 0.11 mg/kg flunixin meglumine into the GV1 acupoint (FGV). Behavioral parameters were assessed 12 hours before the procedure (baseline) and at 4, 6, 12, and 2...
BEVA primary care clinical guidelines: Analgesia. Primary care guidelines provide a reference point to guide clinicians based on a systematic review of the literature, contextualised by expert clinical opinion. These guidelines develop a modification of the GRADE framework for assessment of research evidence (vetGRADE) and applied this to a range of clinical scenarios regarding use of analgesic agents. Key guidelines produced by the panel included recommendations that horses undergoing routine castration should receive intratesticular local anaesthesia irrespective of methods adopted and that horses should receive NSAIDs prior to surgery (ove...
Neuromas at the castration site in geldings. Inguinal pain, unexplained hind limb lameness, back pain or behavioural problems in geldings could be attributable to painful neuromas that develop as a consequence of crushing and severing the testicular nerves during castration. The presence of neuroma in this anatomical location has never been reported, hence the knowledge of possible clinical relevance is limited. The aim of this study was to histologically investigate the testicular nerves at the castration site in geldings for the presence of neuromas. Proximal spermatic cord remnants were collected from 20 geldings admitted to routine p...
Plasma concentrations at two dexmedetomidine constant rate infusions in isoflurane anaesthetized horses: a clinical study. To determine dexmedetomidine plasma concentrations at two infusion rates in isoflurane anaesthetized horses and compare cardiovascular effects and anaesthetic recovery between treatments. Methods: Prospective, randomized, masked clinical study. Methods: Healthy, adult, client-owned, non-food producing horses presented for castration. Methods: Premedication consisted of acepromazine, romifidine and morphine, and anaesthesia was induced with ketamine and midazolam. The horses were randomized to receive dexmedetomidine 0.5 μg kg hour (treatment DL, n = 7) or 1.75 μg kg hour (treatment DH, n =...
Comparison of the Effects of Five Semen Extenders on the Quality of Frozen-Thawed Equine Epididymal Sperm. Cryopreservation of epididymal sperm allows the saving of genetic material in case of unexpected death or emergency castration. The aim of the present study was the comparison of five different combinations of extenders commercially available for equine frozen semen processing for cryopreservation of epididymal sperm. Epididymal sperm were harvested from gonads of 10 healthy stallions after routine castration by retrograde flush technique. Then, samples were split and diluted with (1) INRA96 + INRA Freeze, (2) BotuSemen + BotuCRIO, (3) EquiPlus + Gent Freeze, (4) EquiPlus + EquiPlus Freeze...
Effects of lidocaine on equine ejaculated sperm and epididymal sperm post-castration. In equids, it is common to inject lidocaine into the testicles at the time of routine castration to provide analgesia. The effects of lidocaine on equine sperm have not been evaluated in vitro or on epididymal sperm collected following castration. The aims of this study were to determine effects of clinically relevant doses of lidocaine on equine spermatozoa in vitro using freshly collected semen and to compare the characteristics of epididymal spermatozoa after routine castration with or without intra-testicular lidocaine administration. We hypothesized that increasing concentrations of lid...
Equine Welfare in Practice: A Collaborative Outreach and Education Program with Michigan State University, Universidad Nacional Autónoma de México, and Universidad Veracruzana. There is great need for veterinary care for working equids worldwide. Addressing this need provides an opportunity for veterinary students to gain primary care experience. An annual two week collaborative outreach and educational program with Michigan State University (MSU), the Universidad Nacional Autónoma de México (UNAM) and the Universidad Veracruzana (UV) was developed to provide care for working equids in rural Mexican communities. From 2017 to 2019 24 US veterinary students and 25 Mexican veterinary students, interns and residents examined, vaccinated and dewormed more than 2200 equi...
A comparison of two ketamine doses for field anaesthesia in horses undergoing castration. Ketamine at 2.2 mg/kg given i.v. is often used to induce anaesthesia for surgical procedures in horses under field conditions. Commonly, additional doses are needed to complete the surgery. We hypothesised that surgical conditions would be improved when 5 mg/kg of ketamine was used to induce anaesthesia, while induction and recovery qualities would not differ from those when 2.2 mg/kg ketamine was used. Objective: To compare the anaesthetic effects of two ketamine doses (5 and 2.2 mg/kg) during field anaesthesia for castration of horses. Methods: Prospective, randomised, blinded, clinical stud...
Lower allergen levels in hypoallergenic Curly Horses? A comparison among breeds by measurements of horse allergens in hair and air samples. Exposure to horses can cause severe allergic reactions in sensitized individuals. The breed, American Bashkir Curly Horse is categorized as hypoallergenic, primarily due to reports of allergic patients experiencing fewer symptoms while handling this special breed. The possible reasons for this phenomenon could be lower allergen production and/or reduced allergen release into the air because of increased sebum content in their skin and hair compared to other breeds. Therefore, the aim of the current study was to compare different horse breeds in relation to allergen content in hair and airborne...
A prospective multicentre survey of complications associated with equine castration to facilitate clinical audit. Despite the regularity with which castration is performed, the types of complications and current best practice are unknown. Objective: The objective of this study was to perform a prospective audit of routine equine castrations performed in general practice to determine complication rates and factors associated with them. Methods: Multicentre, prospective audit of castrations. Methods: Data on castrations were collected on the day of surgery from 18 veterinary practices; 30-days post-operatively follow-up was obtained and complications recorded. Frequency of complications was reported, and mu...
Complications associated with closed castration using the Henderson equine castration instrument in 300 standing equids. To describe a closed castration technique in standing equids, report associated complications, and identify potential risk factors. Methods: Prospective cohort study of 300 standing equids that were castrated with the Henderson Equine Castrating Instrument. Methods: Thirteen participating veterinarians recorded intraoperative difficulties and postoperative complications. Descriptive statistics, univariate analyses with Fisher's exact tests, and logistic regressions were used to evaluate intraoperative difficulties and postoperative complications and to assess risk factors for postoperative com...
Surgical management of postcastration spermatic cord stump infection in horses: A retrospective study of 23 cases. To report the surgical management and the short- and long-term follow-up of postcastration spermatic cord infection in horses. Methods: Retrospective case series. Methods: Twenty-three client-owned horses. Methods: Medical records (2001-2017) of horses that had been surgically treated for spermatic cord stump infection after castration were reviewed. Time from castration to presentation, diagnostic procedures, surgical complications, bacterial culture and ancillary testing, and survival to discharge were collected. Long-term follow-up was obtained by owner survey when possible. Descriptive sta...
Minimally invasive, compartmentalized, modified open castration technique with primary closure in equids. OBJECTIVE To describe use of a modified open castration technique with a scrotal approach and primary closure in equids. DESIGN Prospective case series. ANIMALS 38 client-owned, sexually intact male equids. PROCEDURES With owner consent, elective castration was performed with a modified open technique on patients (1 pony, 1 miniature horse, and 36 horses of other breeds) under general anesthesia. The procedure included minimal dissection into the scrotal region for removal of testes, with cremaster muscles left intact and the parietal vaginal tunic closed in place. Primary closure of surgical ...
Prevalence of complications associated with use of the Henderson equine castrating instrument. Castration is one of the most common surgical procedures performed in the horse. Complication rate and types of complications associated with use of the Henderson equine castrating instrument have not been determined. Objective: To determine the complication rate and type of complications encountered when using the Henderson equine castrating instrument in equine ambulatory practice. Methods: Retrospective case series. Methods: Medical records of horses undergoing routine castration using the Henderson drill were identified and evaluated for the occurrence of complications. The relationship be...
Local mepivacaine before castration of horses under medetomidine isoflurane balanced anaesthesia is effective to reduce perioperative nociception and cytokine release. In horses castration with primary intention healing is usually performed under balanced inhalation anaesthesia. To optimise analgesia, the use of local anaesthesia was tested. Objective: To investigate the effect of local mepivacaine before castration with first intention healing under balanced medetomidine-isoflurane anaesthesia and flunixin meglumine, morphine analgesia on perioperative cytokine levels and pain in horses. Methods: Prospective blinded clinical study. Methods: Twenty stallions were randomly assigned to control or mepivacaine groups. Flunixin meglumine was administered before s...
Using the Five Domains Model to Assess the Adverse Impacts of Husbandry, Veterinary, and Equitation Interventions on Horse Welfare. The aim of this study was to conduct a series of paper-based exercises in order to assess the negative (adverse) welfare impacts, if any, of common interventions on domestic horses across a broad range of different contexts of equine care and training. An international panel (with professional expertise in psychology, equitation science, veterinary science, education, welfare, equestrian coaching, advocacy, and community engagement; = 16) met over a four-day period to define and assess these interventions, using an adaptation of the domain-based assessment model. The interventions were consid...
Maternal parity affects placental development, growth and metabolism of foals until 1 year and a half. Primiparous mares are known to produce smaller foals than multiparous mares. This difference seems to be partly explained by the reduced exchange surface and volume of the placental villi in primiparous compared to multiparous placentas. The effect of maternal parity on foals' post-natal growth, metabolism and sexual maturation, however, has been given little consideration. The objectives of this work were to analyse placental biometry and structure at term, growth of foals and yearlings, their metabolism and testicular maturation at one year of age. Twenty multiparous mares (M), aged over 6 y...
Survey of equine castration techniques, preferences and outcomes among Australian veterinarians. (1) To collect the perceptions of veterinarians performing equine castrations in Australia on techniques, preferences and outcomes, (2) to investigate veterinarian use and experience with the Henderson castrating instrument and (3) to investigate potential associations between demographics, castration methods and techniques, and complications. Methods: Online survey of members of the Australian Veterinary Association's Special Interest Group, Equine Veterinarians Australia (EVA). Methods: A link to the survey was included in the EVA e-newsletter and practices on the EVA website were contacted ...
Morcellation for testes extraction in horses undergoing standing laparoscopic cryptorchidectomy. The major objective of this study was to describe the use of morcellation for standing laparoscopic cryptorchidectomy in 30 client-owned horses. A second objective was to describe a laparoscopic-assisted standing scrotal technique for removal of a descended testis in unilateral cryptorchids. Morcellation for extraction of abdominal testes is effective, efficient, and well-tolerated. Morcellation enabled safe and straightforward extraction of testes from the abdomen through an approximately 13- to 20-mm incision using a 2-portal technique. No incisional or morcellator-related complications occu...
Evaluation of total intravenous anesthesia with propofol-guaifenesin-medetomidine and alfaxalone-guaifenesin-medetomidine in Thoroughbred horses undergoing castration. Anesthetic and cardiorespiratory effects of total intravenous anesthesia (TIVA) technique using propofol-guaifenesin-medetomidine (PGM) and alfaxalone-guaifenesin-medetomidine (AGM) were preliminarily evaluated in Thoroughbred horses undergoing castration. Twelve male Thoroughbred horses were assigned randomly into two groups. After premedication with intravenous (IV) administrations of medetomidine (5.0 µg/kg) and butorphanol (0.02 mg/kg), anesthesia was induced with guaifenesin (10 mg/kg IV), followed by either propofol (2.0 mg/kg IV) (group PGM: n=6) or alfaxalone (1.0 mg/kg IV) (group AGM...
Open standing castration in Thoroughbred racehorses in Hong Kong: Prevalence and severity of complications 30 days post-castration. Complications following open standing castration (OSC) in Thoroughbred racehorses are well recognised but variation in their prevalence and severity between populations is not well documented. Objective: To describe the prevalence and severity of complications in the 30 days following OSC. Methods: A retrospective cohort study of veterinary clinical records relating to horses that underwent OSC between July 2007 and July 2012. Methods: Complications were graded on a severity score from N, no complications, to C3, severe complications. Additional data were accessed for each horse including age,...
Evaluation of the use of midazolam as a co-induction agent with ketamine for anaesthesia in sedated ponies undergoing field castration. There are limited investigations comparing ketamine to a ketamine-midazolam co-induction. Objective: To compare quality and safety of general anaesthesia induced using ketamine alone with anaesthesia co-induced using ketamine and midazolam. Methods: Randomised, double blinded, placebo controlled trial. Methods: After i.v. detomidine (20 μg/kg) thirty-eight ponies undergoing field castration received either 0.06 mg/kg (0.6 mL/50 kg) midazolam (group M) or 0.6 mL/50 kg placebo (group P) with 2.2 mg/kg ketamine i.v. for anaesthetic induction. Quality of anaesthetic induction, endotracheal intuba...
Do different characteristics of two emasculators make a difference in equine castration? The Serra and Reimer emasculators are frequently used in equine orchiectomy. They differ in jaw profile and the mechanism by which they achieve haemostasis. Objective: To investigate whether the haemostatic capacities of the Reimer and Serra emasculators in open and closed castration differ, to compare the haemostatic capacities of each emasculator in both open and closed castration, and to assess whether the tensile strength of the parietal tunic in closed castration differs according to whether a Reimer or Serra emasculator is used. Methods: Ex vivo randomised study. Methods: Eighty equine c...
Pharmacokinetics of the anti-androgenic drug flutamide in healthy stallions. Alternatives to surgical castration are necessary for controlling the sexual behaviour of stallions with breeding potential in training and competition. Flutamide is a potent selective non-steroidal androgen receptor competitive antagonist that has been used in human beings as an anti-androgenic drug. In this study, the pharmacokinetics and bioavailability of flutamide and its main active metabolite, 2-hydroflutamide, were determined in seven healthy mature stallions. Single doses of flutamide (1mg/kg intravenously, 1mg/kg orally in fasted horses, 5mg/kg orally in fasted horses and 5mg/kg oral...
Two complementary methods to control gonadotropin-releasing hormone vaccination (Improvac®) misuse in horseracing: Enzyme-linked immunosorbent assay test in plasma and steroidomics in urine. Since the availability on the European market of the vaccine Improvac® dedicated to male pig immunological castration, the risk of misuse of this product in horses is now considered as a threat for the horseracing industry. Immunological castration is not allowed by the racing codes (immune system, Article 6). Indeed, this vaccination against the hypothalamic hormone luteinizing hormone-releasing hormone or gonadotropin-releasing hormone (GnRH) will prevent the release from the anterior pituitary of luteinizing hormone and follicle stimulating hormone, which are required for the development a...
Relationship between echotextural and histomorphometric characteristics of stallion testes. The goal of this study was to investigate correlations between objective measures of testicular echotexture and histomorphometric attributes related to the histological composition of stallion testes. Fifty-four scrotal testes were obtained from three groups of stallions during routine castrations: colts <1 yr old (n = 18), young stallions 1-5 yrs old (n = 27), mature stallions > 5 yrs old (n = 9). In addition, two scrotal testes with degeneration, 16 retained inguinal and 10 retained abdominal testes were surgically obtained. Cross-sectional and longitudinal ultrasonograms were obt...
Complications and risk factors of castration with primary wound closure: Retrospective study in 159 horses. Castration with primary wound closure reportedly has lower complication rates and shorter recovery periods compared to castration with second intention healing. However, little is known about risk factors associated with complications using primary wound closure. Medical records of 159 horses castrated and having primary wound closure were reviewed. Main short-term complications were: scrotal hematoma in 12 horses (7.6%), signs of colic in 6 horses (3.8%), fever in 4 horses (2.5%), and peri-incisional edema in 3 horses (1.9%). As for long-term complications, 24 out of 105 (23%) horses sustaine...