Veterinary procedures in horses encompass a range of medical and surgical interventions performed to diagnose, treat, and manage equine health conditions. These procedures are designed to address various health issues, from routine care to emergency interventions. Common veterinary procedures include vaccinations, dental care, lameness evaluations, reproductive services, and surgical interventions such as colic surgery or fracture repair. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, outcomes, and advancements in veterinary procedures for horses, providing insights into their application and efficacy in equine medicine.
Schaer BL, Ryan CT, Boston RC, Nunamaker DM.There is a need to determine accelerations acting on the equine hoof under field conditions in order to better assess the risks for orthopaedic health associated with shoeing practices and/or surface conditions. Objective: To measure the acceleration profiles generated in Thoroughbred racehorses exercising at high speeds over dirt racetracks and specifically to evaluate the effect of a toe grab shoe compared to a flat racing plate, using a newly developed wireless data acquisition system (WDAS). Methods: Four Thoroughbred racehorses in training and racing were used. Based on previous trials, e...
Chaney KP, Holcombe SJ, LeBlanc MM, Hauptman JG, Embertson RM, Mueller PO, Beard WL.Anecdotal speculation suggests that prognosis for survival of mares and foals following correction of uterine torsion has improved over the past 30 years. Objective: To determine statistically the outcome of uterine torsion according to duration of clinical signs, stage of gestation, parity, physical examination findings, method of correction, prognosis for survival and reproductive health of the mare, and prospects for the foal within the neonatal period. Methods: This retrospective study combined cases from 4 equine referral hospitals. Results: The stage of gestation at which uterine torsion...
Schnabel LV, Bramlage LR, Mohammed HO, Embertson RM, Ruggles AJ, Hopper SA.Studies on arthroscopic removal of apical proximal sesamoid fracture fragments in Thoroughbred (TB) horses age > or = 2 years have reported a high success rate. However, there are no reports documenting the racing prognosis of TB horses that undergo such surgery as weanlings or yearlings. Objective: To describe the incidence of apical proximal sesamoid fractures in immature TB horses, age < 2 years and determine probability and quality of racing performance after arthroscopic removal of such fractures in 151 TB weanlings and yearlings. Methods: The medical records of TB horses age < 2 years th...
Vandeweerd JM, Desbrosse F, Clegg P, Hougardy V, Brock L, Welch A, Cripps P.The distal limb innervation of the horse has been studied extensively to allow use of local anaesthetic techniques to detect the origin of pain in lameness. However, the innervation of the lumbar spine has so far been poorly described and a more precise description may assist clinicians to localise back pain in the horse. Objective: To gain better knowledge of the innervation of the lumbar spine and identify salient anatomical features that might be used for diagnostic and therapeutic ultrasound guided injections. Methods: The spines of 8 mature horses were dissected. Branches of the dorsal ra...
Maes A, Weiland L, Sandersen C, Gasthuys F, De Backer P, Croubels S.A sensitive method for the quantification of lidocaine and its metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), in animal plasma using high-performance liquid chromatography combined with electrospray ionization mass spectrometry is described. The sample preparation includes a liquid-liquid extraction with methyl tert-butylmethyl ether after addition of 2M sodium hydroxide. Ethylmethylglycinexylidide (EMGX) is used as an internal standard. For chromatographic separation, an ODS Hypersil column was used. Isocratic elution was achieved with 0.01 M ammonium acetate and aceto...
Pusterla N, Mapes S, Leutenegger CM.A questionnaire was developed to document the knowledge base of large-animal diplomates of the American College of Veterinary Internal Medicine (ACVIM) regarding polymerase chain reaction (PCR) technology and to identify the common use of this technology in equine practice. Ninety-three of the 278 mailed questionnaires were returned, for an overall response rate of 33.4%. Ninety respondents (99%) reported being familiar with the general principles of nucleic acid probe technology; however, only 52 (57%) knew the difference between conventional (traditional) and real-time (second-generation) PC...
Machnik M, Hegger I, Kietzmann M, Thevis M, Guddat S, Schänzer W.The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentr...
Dykgraaf S, Dechant JE, Johns JL, Christopher MM, Bolt DM, Snyder JR.To determine the effect of intrathecal amikacin administration and repeated tenovaginocentesis on the total nucleated cell count (TNCC), total protein (TP) concentration and cytologic characteristics of synovial fluid of the equine digital flexor tendon sheath (DFTS). Methods: Randomized, cross-over experimental design. Methods: Adult horses (n=8). Methods: Synovial fluid was aseptically collected from the DFTS and either 1 mL amikacin sulfate (250 mg/mL) or lactated Ringer's solution (LRS) was injected into the DFTS. Serial synovial fluid samples were obtained at 0, 12, 24, 48, and 72 hours. ...
Bourges-Abella N, Raymond-Letron I, Diquelou A, Guillot E, Regnier A, Trumel C.To describe the cells observed in conjunctival brush cytology (CBC) from normal horses and compare these findings with conjunctival structural histology so as to understand which cells are recovered from CBC. Methods: This study was divided into three parts. (1) Conjunctival brush smears were collected from 20 healthy horses on both eyes and a differential count on 300 cells was carried out on May Grünwald-Giemsa (MGG) smears. (2) A similar protocol was used for whole eyes from five horses obtained rapidly after death from a slaughterhouse. The eyes were then assessed for conjunctival histolo...
Plummer CE, Smith S, Andrew SE, Lassaline ME, Gelatt KN, Brooks DE, Kallberg ME, Ollivier FJ.The purpose of this study was to evaluate the effectiveness of postoperative beta-irradiation with strontium-90 as an adjunctive treatment to superficial keratectomy and permanent bulbar conjunctival graft for removal of equine corneolimbal squamous cell carcinoma (SCC), in decreasing recurrence rate. Methods: The retrospective case study included 38 horses diagnosed and treated for SCC of the eye that involved the limbus and/or cornea. The patients were treated between 1990 and 2002, with strontium-90 irradiation immediately after corneal and conjunctival graft surgery. Recurrence was defined...
Scheuch E, Spieker J, Venner M, Siegmund W.The long-acting antibiotic tulathromycin is on the marked for treatment of pulmonary infection of cattle, swine and horses. To measure disposition and distribution of tulathromycin in foals, a high throughput method was developed for horse plasma (calibration range: 0.006-0.8 microg/mL) and broncho-alveolar cells (calibration range: 0.1-4.0 microg/10(9)cells) using tandem mass spectrometry. Tulathromycin was extracted from plasma and broncho-alveolar fluid using cation exchange cartridges with acetonitrile/ammonia (95:5, v/v). The chromatography was performed isocratically with a mobile phase ...
Brown DL, Anderson M, Cullen JM.Mesenchymal hamartoma of the liver is a rare congenital disorder of biliary tract development. During the necropsy of a late-term equine fetus, a markedly enlarged liver of more than two times normal weight was found. Light microscopic review revealed that the normal hepatic parenchyma had been obliterated, replaced, and expanded by abnormal bile ducts surrounded by abundant, myxoid stroma. The lesion was diagnosed as a mesenchymal hamartoma. Small portions of the liver had bridging septa of fibrosis and proliferations of small-caliber abnormal bile ducts, resembling another congenital biliary...
Mills PC.The effects of three vehicles, phosphate-buffered saline (PBS), ethanol (50% in PBS w/w) and propylene glycol (50% in PBS w/w) on in vitro transdermal penetration of testosterone was investigated in the horse. Skin was harvested from the thorax of five Thoroughbred horses after euthanasia and stored at -20 degrees C until required. The skin was then defrosted and placed into Franz-type diffusion cells, which were maintained at approximately 32 degrees C by a water bath. Saturated solutions of testosterone, containing trace amounts of radiolabelled [14C]testosterone, in each vehicle were applie...
Rainger JE, Dart AJ.Enteral fluids administered alone, or in conjunction with intravenous fluids, are reported to be useful for the treatment of dehydration and electrolyte loss associated with diarrhoea in a number of species, following exercise in horses and for feed impaction of the large intestine of horses. Enteral fluids are suitable for treatment of mild to moderately dehydrated patients with some intact intestinal epithelium and motile small intestine. In patients that will drink voluntarily or tolerate nasal intubation the use of enteral fluids may avoid the complications associated with intravenous flui...
James FM, Parente EJ, Palmer JE.A 1-day-old Standardbred foal with a history of extreme respiratory distress after birth consistent with upper airway obstruction was evaluated. A temporary tracheostomy tube was placed by the referring veterinarian. Results: On initial examination, there was evidence of hypoxic-ischemic syndrome, secondary to perinatal asphyxia. Endoscopy revealed obstruction of both nares at the level of the choanae; a diagnosis of bilateral choanal atresia was made. Results: The foal was anesthetized and underwent transendoscopic laser fenestration of the buccopharyngeal membranes. Three weeks after surgery...
Joyce J, Hendrickson DA.To compare pain responses in stallions undergoing standing laparoscopic cryptorchidectomy following intratesticular or mesorchial infiltration of lidocaine. Methods: Clinical trial. Methods: 20 stallions with 1 or 2 undescended testes. Methods: Standing horses were administered a nonsteroidal anti-inflammatory drug and a caudal epidural injection of detomidine hydrochloride and underwent laparoscopic cryptorchidectomy. The undescended testis (1/horse) was grasped to determine the preoperative pain response (present vs absent) and assess severity of pain (by use of a visual analog scale [VAS])....
Kelmer G, Kramer J.Shortening of the deep digital flexor tendon was performed by tenotomy, overlapping and anastomosis. The procedure was performed on a two-year-old Quarter Horse Mare with distal interphalangeal joint hyperextension with subluxation and metatarsophalangeal joint hyperextension. These problems originated from damage to the digital flexor tendons, presumably due to previous distal limb trauma. The procedure markedly improved the mare's level of comfort, degree of ambulation and limb conformation. Two years following surgery the mare was comfortable at pasture.
Voermans M, van der Velden MA.A 2-year-old unilateral inguinal cryptorchid Frisian stallion was castrated by bilateral laparoscopic intra-abdominal spermatic cord transection. Because blood testosterone levels were still high on postoperative day 7, both testicles were removed using an open approach. Pathology revealed the presence of vital Leydig-cells in both testes. Failure of the laparoscopic castration in this horse was attributed to an alternate blood supply to the testes by vessels derived from the cremaster and/or external pudendal artery.
Veeramachaneni DN, Moeller CL, Sawyer HR.Conventional light microscopic evaluation of a seminal ejaculate does not fully avail potential indicators of functional impairment in spermatozoal organelles. The technique of critical quantitative evaluation of morphologic features of individual structural components of spermatozoa at a light microscopic level in conjunction with critical qualitative evaluation of spermatozoal organelles at an ultrastructural level, as described in this article, is a valuable clinical tool. Compared with a battery of sperm function assays used in human andrology clinics, this relatively less expensive and si...
Wolfsdorf KE.Methods to manage twins after fixation include natural reduction,dietary reduction, transvaginal ultrasound-guided aspiration,surgical removal, craniocervical dislocation, and transabdominal ultrasound-guided injection. Of these, results have been inconsistent with regard to producing a single healthy foal, except for craniocervical dislocation. This new technique enables the twin to be reduced before complete placenta formation has occurred, allowing the remaining fetus to use the entire endometrial surface and grow to its full potential.
Hendrickson D.Laparoscopic surgery has become commonplace in the field of equine urogenital surgery. As with most surgical procedures, the limiting factors in developing new surgical techniques are limited to the patient size and demeanor, the skills of the surgeon, and the available equipment. Some of the greatest benefits of laparoscopic surgery in the horse include better visualization of the important structures; tension-free amputation of the testes or ovaries,which generally leads to less postoperative pain; and the ability to evaluate the transected stump carefully to make sure there is no hemorrhage...
Kútvölgyi G, Stefler J, Kovács A.A simple trypan blue-neutral red-Giemsa staining procedure for simultaneous evaluation of acrosome, sperm head, and tail membrane integrity and morphology has been used to evaluate equine spermatozoa. Some special characteristics and problems have arisen in evaluating stallion semen. One problem was the differentiation of intact vs. damaged sperm tails primarily in frozen and thawed samples. After freezing and thawing, a high percentage of spermatozoa with an unstained head and stained tail were observed. These cells are considered immotile. Therefore, unambiguous differentiation of intact vs....
McCue PM, Roser JF, Munro CJ, Liu IK, Lasley BL.The granulosa cell tumor is the most common ovarian tumor in mares. A clinical diagnosis can be made based on the presence ofa unilaterally enlarged ovary and a small inactive contralateral ovary. Endocrine testing may be beneficial to confirm a diagnosis. Surgical removal of the tumor eliminates the adverse effect on pituitary function and results in resumption of follicular development and ovulation in the opposite ovary over time.
Carnevale EM.Vitrification can be used successfully to cryopreserve equine embryos. Embryos for vitrification should be collected from donor mares' uteri when they are 300 mm or less in diameter, however,and at the morula or early blastocyst stage of development. No special equipment is required for vitrification; the straw containing the embryo is exposed to vapor for 1 minute before plunging it into liquid nitrogen. Warming of the straw requires no special equipment,and the embryo can be transferred directly from the straw into a recipient's uterus. Vitrification has been repeatedly successful when the p...
Hendrickson D.Laparoscopic surgery has become commonplace in the field of equine urogenital surgery. As with most surgical procedures, the limiting factors in developing new surgical techniques are limited to the patient size and demeanor, the skills of the surgeon, and the available equipment. Some of the greatest benefits of laparoscopic surgery in the horse include better visualization of the important structures; tension-free amputation of the testes or ovaries,which generally leads to less postoperative pain; and the ability to evaluate the transected stump carefully to make sure there is no hemorrhage...
Howard RD, Stashak TS.Traumatic injuries to the head region of the horse are a common presenting complaint. Because of a copious blood supply, these wounds typically exhibit a tremendous capability for healing. By following the basic principles of wound management and employing a few techniques unique for specific injuries, the healing of these wounds can result in a satisfactory outcome.
Hopster K, Watkins AR, Hurcombe SD.To compare the antinociceptive effects of morphine administered via cervical epidural catheter to intravenously administered morphine using a thermal threshold (TT) testing model in healthy adult horses. Methods: Prospective, randomized, blinded experimental study. Methods: A total of six university-owned adult horses. Methods: Horses were instrumented with a cervical (C1-C2) epidural catheter and TT testing device with probes at withers and thoracic limb coronary bands. All horses underwent three TT testing cycles including cervical epidural morphine administration (treatment EpiM; 0.1 mg kg-...
Regnier A, Martin C, Semin MO, Lienard E, Geffre A, Douet JY, Raymond-Letron I.An 18-month-old Arabian-English filly resident in southwest France was referred for evaluation of a conjunctival mass in the right eye (OD). A pink, solid, and mobile nodular formation, measuring approximately 1.2 × 0.8 cm was found under the superior nasal bulbar conjunctiva during an ophthalmic examination that was otherwise normal. The mass was surgically removed using a standing procedure. Cytological examination of fine-needle aspirates from the mass revealed a mixed eosinophilic-lymphocytic inflammation. Histological examination confirmed the dense and diffuse eosinophilic-lymphocyti...
Boles CL, Kohn CW.OF 207 horses with colic seen over a 36-month period, 10 were determined to have impaction colic caused by ingestion of synthetic fencing material. In 6 cases, there was history of exposure to rubberized fencing products. All horses affected were less than or equal to 3 years of age, had signs of mild to moderate abdominal pain, and were unresponsive to usual symptomatic therapy. At surgery, each horse was found to have an impaction involving the distal right dorsal colon, transverse colon, or small colon, and in some cases, all 3 bowel segments. In 9 cases, the involved segment of bowel could...
Baxter GM, Doran RE, Allen D.Proximal open comminuted fractures of the fourth metatarsal bone (Mt IV) in eight horses were treated by complete removal of the affected bone and antimicrobial therapy. Two horses had concurrent septic arthritis of the tarsocrural or distal tarsal articulations, and five horses had radiographic evidence of osteomyelitis and sequestration of the affected bone. Five horses became athletically sound for their intended use, two horses with septic arthritis had residual lameness but were pasture sound, and one horse was lost to follow-up. Excision of the entire bone appears to be an acceptable tre...
Cillán-Garcia E, Taylor SE, Townsend N, Licka T.To report a surgical technique that allows decompression and anatomic re-alignment for management of subluxation of the atlantoaxial articulation. Methods: Clinical report. Methods: Four-year-old Welsh Section B pony gelding. Methods: Attempts at closed reduction of subluxation of the atlantoaxial articulation under general anesthesia were unsuccessful, so a ventral surgical approach allowing partial ostectomy of the dens of the axis was used to facilitate reduction. Results: Recovery from surgery was uneventful and the pony remained comfortable without neurologic deficits. Both neck stiffness...
Parry BW.The clinical, surgical and/or necropsy diagnosis of 79 horses admitted to a referral clinic for evaluation of colic are reported. Twenty-one horses were presented with conditions amenable to medical treatment and all were subsequently discharged. Exploratory laparotomies were performed on 44 horses during the present study, in some cases as a diagnostic procedure preceding euthanasia. In general, in surgical cases the mortality rate was highest for problems involving the small intestine, followed by those affecting the large colon and then the small colon. Postoperative sequelae included perit...
Johnson SA, Richards RB, Frisbie DD, Esselman AM, McClure SR.Over the past three decades, electrohydraulic extracorporeal shock wave therapy (ESWT) as a treatment modality for equine orthopaedic disorders has sparked exponential interest among practitioners, but its clinical applications are quickly evolving and a current review highlighting modernised equine clinical use is lacking. The objective of this review is to summarise the most current ESWT technology, evidence for its use, proposed mechanisms of action and clinical applications in horses while also highlighting the areas requiring further investigation. The three ways to generate a shock wave ...
Taylor TS, Watkins JP, Schumacher J.A temporary indwelling liner was surgically installed in 17 horses with grade III or grade IV rectal tears. The rectal tears of 9 of the horses healed. The remaining 8 horses developed peritonitis as a result of peritoneal contamination before surgery, a change in grade of the tear, or material failure.
Tetens J, Tulleners EP, Ross MW, Orsini PG, Martin BB.Tympany of the auditory tube diverticulum was treated in 2 Standardbred foals by fenestrating the median septum, using an endoscopically placed Nd:YAG laser. Recurrence in 1 foal was treated by enlarging the fenestration, using a modified Whitehouse approach, and the pharyngeal opening of the auditory tube. Use of the Nd:YAG laser eliminates the risk of inadvertent cranial nerve damage associated with incisions into the auditory tube diverticulum. The procedure can be performed with the horse sedated or anesthetized. Clinical signs can recur in the fenestration heals closed or if the condition...
Hackett ES, Hassel DM.Colic is a serious disease of the horse and may require surgical correction. Postoperative complications may result in an increase in short-term morbidity and mortality. Commonly encountered nonsurgical complications are detailed. Anticipation and timely treatment of common postoperative complications after colic surgery may improve overall survival.
Seabaugh KA, Selberg KT, Mueller POE, Eggleston RB, Peroni JF, Claunch KM, Markwell HJ, Baxter GM.Osteoarthritis (OA) of the centrodistal (CD) and tarsometatarsal (TMT) joints is a common cause of lameness in horses. Intra-articular diagnostic anaesthesia and/or therapeutic injection are relied upon to help diagnose and treat many horses with OA of these joints. Objective: The objective of this study was to determine the accuracy of arthrocentesis of the CD and TMT joints using a sample population of equine surgeons and surgery residents. Methods: Randomised experimental study. Methods: Six operators each injected four CD and four TMT joints in 12 sedated horses. The operators were randoml...
Montesso F, Wright IM.Clinical and radiographic examinations of three horses with histories of trauma and/or wounds to the stifle revealed chip fractures from the medial trochlear ridge of the femur of one of them and from the lateral ridges of the femurs of the others. The joints were evaluated and the fragments of bone were removed by arthroscopy. The results were good in all three horses.
Wada S, Yoshinari M, Mizuno Y.Therapeutic soft contact lenses (TSCL) were applied to a thoroughbred racehorse with corneal ulcer refractory to topical medication. The insertion of the TSCL was conducted on day 36 using a nose twitch under sedation, auriculopalpebral nerve block, and topical anesthesia. The lens was retained, with the duration of wear lasting 114 days. Ocular pain improved immediately and fluorescein tests were negative 17 days after insertion. The horse was able to undergo training and ran in two races while wearing the TSCL. Thus a TSCL was found to be clinically useful for treating corneal ulcers in race...
Speirs VC, van Veenendaal JC, Christie BA, Lavelle RB, Gay CC.Three cases of intramural haematoma of the small colon of horses are presented. In all cases the haematoma obstructed the lumen and caused an accumulation of faeces and gas. The horses were in shock and had acute abdominal pain. Exploratory abdominal surgery revealed the haematomas and showed them to be associated with chronic infection and terminal rupture in one animal which was subsequently killed, and an iatrogenic perforation of the terminal small colon in another which survived after intestinal resection. In the remaining horse, which died without recovering after intestinal resection, n...
Halnan CR.The prognostic use of karyotyping in equine breeding has been recommended since 1976. Specimens used and laboratory methods are described. The system of karyotype evaluation is explained together with a glossary of terms. The principal aberrations in horses are defined. The present state of knowledge in cytogenetics in horses is reviewed dealing with infertility in the mare, where sex chromosomes give clear indication of problems; the situation with respect to anomalies found in stallions and hermaphroditism is explained coupled with recent concepts of chromosomal roles in reproduction. The fu...