Euthanasia in horses refers to the process of humanely ending the life of a horse to alleviate suffering or when the quality of life is deemed unsustainable. This practice is considered in cases of severe illness, injury, or chronic pain where recovery is not possible. The decision-making process involves veterinarians, horse owners, and sometimes ethical and welfare considerations. Various methods are employed, with the primary aim of ensuring a painless and stress-free experience for the animal. This page compiles peer-reviewed research studies and scholarly articles that explore the ethical considerations, methods, decision-making processes, and impacts on equine welfare related to euthanasia.
Fletcher KA, Benedetti B, Limon G, Grist A, Padalino B, Hernández-Gil M, Gibson TJ.There has been limited research into the effectiveness of penetrating captive bolt (PCB) for stunning horses () at slaughter. This study observed 100 horses at a commercial abattoir in Mexico, stunned using pneumatic PCB. Animals were assessed at the time of stunning and immediately after for signs of effective/ineffective stunning and shot positioning, with macroscopic gross brain pathology conducted to determine brain trauma. Twenty-five percent (25/100) received more than one shot and 28% (28/100) displayed behavioural signs of ineffective stunning. Of these 28 animals, all had deviations o...
Kelemen Z, Vogl C, Torres Borda L, Auer U, Jenner F.Clinical care for patients with limited life expectancy often requires adjustments, prioritizing immediate benefits over long-term outcomes, as the relevance of future complications diminishes. This study identifies indicators of mortality risk in horses with chronic orthopaedic conditions to enhance individualized care and welfare. Over 3 years, 123 chronically lame horses and 6 healthy control horses at an animal sanctuary underwent regular (every 3 months) comprehensive health assessments and activity monitoring using wearable sensors. Data collected included body condition scores, muscul...
Boocock H, Flyps J, Escobar A, Redondo JI, Taylor PM, Gozalo-Marcilla M, Johnston GM, Bettschart-Wolfensberger R, Sullivan R.Equid anaesthetic mortality is of interest to practitioners. Data for donkey and hybrid mortality have not been specifically described. The main aim of this worldwide observational, prospective, multicentre cohort study was to report on mortality in the 7 days following a general anaesthetic or standing sedation in donkeys and hybrids. This study hypothesised that donkeys and hybrids would have higher mortalities compared to horses. Data were collected as part of the fourth Confidential Enquiry into Perioperative Equine Fatalities (CEPEF4). A total of 825 cases were included, with 757 donkeys ...
Schlote MT, Drozdzewska K, Ehrle A, Lischer C, Gehlen H.This case report describes the use of computed tomography for the diagnosis and surgical planning in a horse with bilateral nephrolithiasis. An adult Warmblood stallion (460 kg) was presented with chronic weight loss, hypercalcemia and azotemia. Ultrasonographic examination identified hyperechoic masses in both kidneys and dilation of the right renal pelvis. A solid mass was evident upon transrectal examination on the left side. Computed tomography (CT) of the caudal abdomen was performed and provided good quality images that facilitated exact determination of the size, position and extent of ...
Cameron A, Geldard M, Mair T, England G, Burford J, Freeman S, Pollock K, Wilson E.Veterinary and charity teams are frequently involved in equine end-of-life decisions. These can cause ethical dilemmas and emotional burdens and complicate communication with owners. Semi-structured focus groups explored experiences of making decisions about end-of-life care and euthanasia at three UK equine veterinary practices and one charity. There were 26 participants in a mix of roles. Inductive coding was conducted during thematic analysis. Major themes generated were 'Equine Welfare', 'Relationships', 'Decision-Making', and 'Emotional Toll and Coping Strategies'. Communication, finances...
Nielsen SS, Alvarez J, Boklund A, Dippel S, Dorea F, Figuerola J, Herskin M, Miranda Chueca MA, Nannoni E, Nonno R, Riber A, Stahl K, Stegeman JA....Horses of different ages may have to be killed on-farm for purposes other than slaughter (where slaughter is defined as killing for human consumption) either individually (i.e. on-farm killing of unproductive, injured or terminally ill animals) or on a large-scale (i.e. depopulation for disease control purposes and other situations, such as environmental contamination, disaster management, etc.). The purpose of this opinion is to assess the hazards and welfare consequences associated with the on-farm killing of horses. The killing procedure is divided into Phase 1 (pre-killing), which includes...
Allen SE, Taylor S, Given J, Verheyen KL.The British horseracing industry is committed to reducing equine fatalities in jump racing. Race-related fatalities are a major welfare concern and threaten the sport's social licence to operate. Objective: To describe the risk of, and determine risk factors for, fatality in British jump racing. Methods: Retrospective cohort. Methods: Analyses included all starts made in British jump races between January 2010 and April 2023. Available information for each horse, race, racecourse, trainer and jockey was collated and combined with details of all fatalities recorded by official veterinary office...
Charles A, Kerckhove HV, De Maré L, Cassart D, Ficheroulle J, Pouyade GR, Tosi I.A Standardbred racehorse was presented for exercise intolerance, weight loss, pyrexia and facial deformity. Radiography and ultrasonography revealed periostitis and regional soft tissue swelling of maxillary bones. Computed tomography excluded any dental or sinus origin of these abnormalities. Further deformities on distal limbs and skin lesions appeared during hospitalization. Radiography identified bilateral periostitis and soft tissue swelling in the distal radius and metatarsal bones, as observed in the head, suggestive of hypertrophic osteopathy (HO). Skin biopsies revealed granulomatous ...
Barton CK, True A, Fenn M, Thampi P, Watson A, Smanik LE.The objective of this Case Report was to describe the clinical manifestation and postmortem findings of a horse evaluated for recurrent colic diagnosed with pyloric aplasia and an ectopic duodenal papilla. Methods: 13-year-old Quarter Horse gelding. Unassigned: The horse was presented to a referral center for signs of colic that were unresponsive to management on the farm. No abnormalities were noted on rectal palpation; however, upon passage of a nasogastric tube, 31 L of net gastric reflux was obtained. Gastroscopy noted grade IV squamous ulceration and moderate glandular ulceration, severe ...
Carpenter AL, Townsend KS, Johnson PJ, Kim DY.An 8-y-old National Show Horse mare was presented for evaluation of pneumonia and laminitis. Harsh bronchovesicular sounds were auscultated throughout both lung fields, and the mare had signs of moderately painful laminitis. Thoracic ultrasonography revealed lung consolidation throughout the dorsal aspect of both lungs, and radiography revealed an extensive diffuse-to-patchy bronchointerstitial lung pattern. The mare's clinical condition rapidly deteriorated, and euthanasia was elected. On postmortem examination, the lungs, omentum, spleen, liver, adrenal glands, kidneys, and femur contained 0...
Giessler KS, Goehring LS, Jacob SI, Davis A, Esser MM, Lee Y, Zarski LM, Weber PSD, Hussey GS.Herpesviruses establish a well-adapted balance with their host's immune system. Despite this co-evolutionary balance, infections can lead to severe disease including neurological disorders in their natural host. In horses, equine herpesvirus 1 (EHV-1) causes respiratory disease, abortions, neonatal foal death and myeloencephalopathy (EHM) in ~10 % of acute infections worldwide. Many aspects of EHM pathogenesis and protection from EHM are still poorly understood. However, it has been shown that the incidence of EHM increases to >70 % in female horses >20 years of age. In this study we use...
Esterl-Byrne LL, Huseman CJ, Haynes C, Kinman LA, Jones TN.The welfare of unwanted horses presents a significant concern for the equine industry. However, there is a lack of research on how unwanted horses are affected by major crises. The drastic changes that resulted from the COVID-19 pandemic presented ample opportunity to investigate how unwanted horses are impacted by challenging circumstances. Study objectives were to evaluate the COVID-19 pandemic's impact on the unwanted horse population and determine the current perceptions of horses in-transition. A 23-question online survey designed using Qualtrics was administered electronically to adults ...
Willis AT, Dahlgren AR, Woolard KD, Ghosh S, Donnelly CG, de la Concha-Bermejillo A, Pacheco A, Watson KD, Berryhill E, Aleman M, Wensley F....In 2020, a novel neurologic disease was observed in juvenile Quarter Horses (QHs) in North America. It was unknown if this was an aberrant manifestation of another previously described neurological disorder in foals, such as equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM). Objective: To describe the clinical findings, outcomes, and postmortem changes with Equine Juvenile Spinocerebellar Ataxia (EJSCA), differentiate the disease from other similar neurological disorders, and determine a mode of inheritance. Methods: Twelve neurologically affected QH foals and the...
Nieforth LO, Kaufman S.Given the nature of horse-human interactions in equine-assisted services (EAS), death of a horse may have significant impacts. In this study, an online survey was distributed to EAS practitioners. The goal of the study was to explore the experiences of practitioners and identify the socioemotional processes that occur upon the death of an equine within an EAS program. Open-ended responses ( = 84) were analyzed qualitatively using a grounded theory and constant-comparative approach. Responses are situated into two themes (1) Processing the death of an equine and (2) Practical implications. Expe...
Kramer AJ, Meziara Wilson T, Kimura S, Groover E, DeLeon-Carnes M, Neto RLALT.A 23-y-old gelding was presented to a veterinary teaching hospital with a history of chronic, refractory diarrhea. Clinically, the horse was in poor body condition, with a thickened and corrugated large intestine identified by transcutaneous abdominal ultrasonography. At postmortem examination following euthanasia, the large colon and cecum had segmental thickening of the intestinal wall with innumerable mucosal ulcers and prominent polypoid mucosal masses. Many mesenteric and hepatic lymph nodes were enlarged. Histology revealed granulomatous and ulcerative typhlocolitis and granulomatous lym...
Barrantes Murillo DF, Cattley RC, Cullen JM, Withers C, Towns J, Pfeifle R, Wooldridge A, Neto RLALT.A 17-y-old Arabian mare was presented to the Auburn Large Animal Veterinary Teaching Hospital with a long-term history of intermittent mild recurrent colic that responded to medical treatment. CBC revealed mild lymphopenia; serum biochemistry findings were of increased gamma-glutamyl transferase and creatine kinase activities, hyperferremia, hyperglycemia, hypomagnesemia, and hypokalemia. Abdominocentesis was compatible with low-protein transudate. Due to the progression and duration of clinical signs, the owner elected euthanasia. Postmortem examination and histopathology confirmed a cholangi...
Romero Corrêa R, Peres Mendes R, Darley Velasquez Piñeros D, De Lima AE, do Valle De Zoppa AL, Lopes Correia da Silva LC, de Francisco Strefezzi R....Preservation of biological tissues has been used since ancient times. Regardless of the method employed, tissue preservation is thought to be a vital step in veterinary surgery teaching and learning. Objective: This study was designed to determine the usability of chemically preserved cadaveric equine heads for surgical teaching in veterinary medicine. Methods: Six cadaveric equine heads were collected immediately after death or euthanasia and frozen until fixation. Fixation was achieved by using a hypertonic solution consisting of sodium chloride, sodium nitrite and sodium nitrate, and an alc...
Vernemmen I, Van Steenkiste G, Buschmann E, Cornelis K, Schauvliege S, Ibrahim L, Decloedt A, van Loon G.Radiofrequency ablation has been successfully applied to treat right atrial arrhythmias in horses. Ablation of left-sided arrhythmias requires a retrograde transarterial approach which is complicated. In human medicine, the left atrium is accessed through transseptal puncture (TSP) of the fossa ovalis (FO) using a caudal approach via the femoral vein. Objective: To develop a zero fluoroscopy TSP technique for horses using a jugular vein (cranial) and transhepatic (caudal) approach. Methods: In vivo experimental study. Methods: Transseptal puncture was performed in 18 horses admitted for euthan...
Benedetti B, Freccero F, Barton J, Elmallah F, Refat S, Padalino B.Working equids are often used to exhaustion, living and dying in conditions below minimal welfare standards. Due to their poor welfare status, euthanasia should be considered in certain conditions. The study aimed to describe the population and the disease frequency of the working equids admitted at an equine clinic in Cairo (i.e., Egypt Equine Aid (EEA)) from 2019 to 2022 and identify possible associations between physical parameters at admission and the outcome. Records of 1360 equids admitted at EEA were reviewed. The majority of the admitted equids were horses (65.6%), followed by donkeys ...
Galinelli NC, Bamford NJ, de Laat MA, Sillence MN, Harris PA, Bailey SR.Insulin dysregulation in horses is characterised by hyperinsulinaemia and/or tissue insulin resistance and is associated with increased risk of laminitis. There is growing evidence in other species that dopamine attenuates insulin release from the pancreas; however, this has yet to be examined in horses. The present study aimed to identify whether there are cells capable of producing or responding to dopamine within the equine gastrointestinal mucosa and pancreas. Tissue samples were collected from the stomach, small and large intestines, and pancreas of six mature horses following euthanasia....
de Preux M, Precht C, Guevar J, Graubner C, Thenhaus-Schnabel S, Buser L, Lukes A, Koch C.A 16-year-old warmblood mare was referred with a progressive history of behavioral changes and left-sided blindness. Following neuroanatomical localization to the forebrain, magnetic resonance imaging of the head revealed a well-delineated, 4.5 cm in diameter, round pituitary mass causing marked compression of the midbrain and optic chiasm. Euthanasia was recommended but declined by the owners. Veterinary specialists and a human neurosurgeon collaboratively prepared for surgical case management. A novel navigated transmandibular lateral transsphenoidal approach was developed to access the re...
Kvigstad EF, Øverland IK, Skedsmo FS, Jäderlund KH, Gröndahl G, Hanche-Olsen S, Gunnes G.Over the past 25 years, acquired equine polyneuropathy (AEP) has emerged as a neurological disease in Scandinavian horses. This condition is characterized by histopathological features including the presence of Schwann cell (SC) inclusions. Cultivated equine SCs would serve as a valuable resource for investigations of factors triggering this Schwannopathy. Ideally, cells should be sampled for cultivation from fresh nerves immediately after death of the animal, however the availability of fresh material is limited, due to the inconsistent case load and the inherent technical and practical chall...
Palomino Lago E, Baird A, Blott SC, McPhail RE, Ross AC, Durward-Akhurst SA, Guest DJ.Fractures caused by bone overloading are a leading cause of euthanasia in Thoroughbred racehorses. The risk of fatal fracture has been shown to be influenced by both environmental and genetic factors but, to date, no specific genetic mechanisms underpinning fractures have been identified. In this study, we utilised a genome-wide polygenic risk score to establish an in vitro cell system to study bone gene regulation in horses at high and low genetic risk of fracture. Candidate gene expression analysis revealed differential expression of and genes in osteoblasts derived from high- and low-risk...
Colbath AC, Fortin JS, Burglass CM, Panek C, Vergara-Hernandez FB, Johnson TN, Robison CA, Logan AA, Nelson NA, Nielsen BD, Schott HC.Pathological fractures have been reported in equids with pituitary pars intermedia dysfunction (PPID) but their prevalence and pathogenesis is unknown. Objective: To compare: (1) bone mineral density (BMD) in weight bearing and nonweight bearing bones in PPID+ equids and aged and young PPID- controls; and (2) biomechanical properties of the fourth lumbar vertebral body in PPID+ equids and aged PPID- equids. Methods: Case-control study: five PPID+ equids and six aged and four young PPID- control horses. Methods: PPID status was based on clinical signs and necropsy examination of the pituitary g...
Andersen C, Jacobsen S, Uvebrant K, Griffin JF, Vonk LA, Walters M, Berg LC, Lundgren-Åkerlund E, Lindegaard C.Integrin α10β1-selected mesenchymal stem cells (integrin α10-MSCs) have previously shown potential in treating cartilage damage and osteoarthritis (OA) and in animal models . The aim of this study was to further investigate disease-modifying effects of integrin α10-MSCs. Methods: OA was surgically induced in 17 horses. Eighteen days after surgery, horses received 2 × 10 integrin α10-MSCs intra-articularly or were left untreated. Lameness and response to carpal flexion was assessed weekly along with synovial fluid (SF) analysis. On day 52 after treatment, horses were euthanized, and carp...
Burrell K, Sutton-Walker G, England GCW, Burford JH, Freeman SL.There is limited evidence on factors affecting critical decision making for horses with colic. This study's aim was to describe the assessment and decision making involved in horses referred for management of colic. Methods: An in-depth case analysis was used to document case presentation, decision making and outcomes for horses referred for colic to two UK equine veterinary practices over a 12-month period. The data recorded included previous history, presenting signs, response to treatment, case outcome and factors affecting decisions for further treatment or euthanasia. Results: Data were a...
Banse HE, Piero FD, Andrews FM, Garcia-Abarca N, Watanabe TTN.To compare small intestinal inflammation with gastric inflammation in horses with and without equine gastric glandular disease (EGGD), we evaluated endoscopic, macroscopic, and microscopic findings of the glandular stomach and microscopic findings of the small intestine. Methods: 36 horses. Methods: Horses underwent endoscopy and were scored for EGGD. After euthanasia, stomachs were collected and macroscopically evaluated. Normal pyloric mucosa, glandular lesions, and small intestinal (duodenum, mid-jejunum, and ileum) samples were collected and processed for microscopic examination. Cellular ...
Stutsel M, Gimeno M, Young A, Bell JW, Horadagoda N.A 2-year-old Standardbred gelding was referred for a mass on the palmaromedial right front pastern which was accompanied by progressively worsening lameness. The mass was firm to palpation and covered by normal skin. Ultrasonographically, a smooth encapsulated mass was present, medial to the flexor tendons and palmar to the neurovascular bundle. Because of a poor prognosis for future athletic performance without surgical or chemotherapeutic intervention and economic constraints preventing further diagnostics and treatment, the horse was euthanised. Post-mortem magnetic resonance imaging, histo...
McIlwraith CW, Frisbie DD, Rodkey WG, Kisiday JD, Werpy NM, Kawcak CE, Steadman JR.This study evaluated intra-articular injection of bone marrow-derived mesenchymal stem cells (BMSCs) to augment healing with microfracture compared with microfracture alone. Methods: Ten horses (aged 2.5 to 5 years) had 1-cm2 defects arthroscopically created on both medial femoral condyles of the stifle joint (analogous to the human knee). Defects were debrided to subchondral bone followed by microfracture. One month later, 1 randomly selected medial femorotibial joint in each horse received an intra-articular injection of either 20 × 10(6) BMSCs with 22 mg of hyaluronan or 22 mg of hyalurona...
Williams RB, Harkins LS, Hammond CJ, Wood JL.For improvements to the safety and welfare of racehorses to be possible, it is essential to have access to basic descriptive information about the veterinary incidents encountered during horseracing. A 3 year surveillance study (1996-1998) was conducted by The Jockey Club into racing injuries, other postrace clinical problems and fatalities from all 59 British racecourses (mainland Britain only) to identify risk factors. During the survey there were 222,993 racing starts: 106,897 starts in flat races on turf (47.9%), 26,519 starts in flat races on all-weather surfaces (11.9%), 30,932 starts in...
Johnston GM, Eastment JK, Wood J, Taylor PM.To document the equine perioperative mortality rate and to highlight any factor associated with an increased risk of death up to 7 days after anaesthesia. Methods: A prospective observational epidemiological multicentre study. Methods: Data were recorded from all equidae undergoing general anaesthesia in 62 clinics. Power calculations indicated that 45 000 cases were required to detect the significance of important variables. Details of each horse, operation, anaesthetic agents and clinic personnel were recorded. Outcome at 7 days was recorded as: alive, put to sleep (PTS) or dead. Data were a...
Frisbie DD, Al-Sobayil F, Billinghurst RC, Kawcak CE, McIlwraith CW.To discriminate between changes in biomarkers with exercise compared to changes in biomarkers with osteoarthritis (OA) in exercising horses. Methods: Sixteen, 2-year-old horses were randomly assigned either to an exercise-alone (n=8) or OA-affected (also exercised) (n=8) group. All horses had both mid-carpal joints arthroscoped and OA induced in one mid-carpal joint in the OA-affected joints of OA-affected horses. Two weeks after surgery all horses commenced a strenuous exercise program on a high-speed treadmill. Clinical outcomes and synovial fluid and serum biomarkers, were evaluated weekly....
Asplin KE, Sillence MN, Pollitt CC, McGowan CM.The purpose of this study was to determine the effects of prolonged administration of insulin, whilst maintaining normal glucose concentrations, on hoof lamellar integrity in vivo on healthy ponies with no known history of laminitis or insulin resistance. Nine clinically healthy, unrelated ponies were randomly allocated to either a treatment group (n =5; 5.9+/-1.7 years) or control group (n =4; 7.0+/-2.8 years). The treatment group received insulin via a euglycaemic hyperinsulinaemic clamp technique modified and prolonged for up to 72 h. Control ponies were infused with an equivalent volume of...
de Laat MA, McGowan CM, Sillence MN, Pollitt CC.Hyperinsulinaemia is known to induce laminitis experimentally in healthy ponies with no history of the condition. Horses are more insulin sensitive than ponies and whether prolonged hyperinsulinaemia and euglycaemia would have a similar laminitogenic effect requires study. Objective: To determine if laminitis results when the prolonged euglycaemic hyperinsulinaemic clamp technique (p-EHC) is applied to clinically normal Standardbred horses, and to monitor hoof wall temperature seeking an association between vascular activity and laminitis development. Methods: Eight young, clinically normal St...
Venter M, Human S, Zaayman D, Gerdes GH, Williams J, Steyl J, Leman PA, Paweska JT, Setzkorn H, Rous G, Murray S, Parker R, Donnellan C, Swanepoel R.Serologic evidence suggests that West Nile virus (WNV) is widely distributed in horses in southern Africa. However, because few neurologic cases have been reported, endemic lineage 2 strains were postulated to be nonpathogenic in horses. Recent evidence suggests that highly neuroinvasive lineage 2 strains exist in humans and mice. To determine whether neurologic cases are being missed in South Africa, we tested 80 serum or brain specimens from horses with unexplained fever (n = 48) and/or neurologic signs (n = 32) for WNV. From March 2007 through June 2008, using reverse transcription-PCR (RT-...
Gerding JC, Gilger BC.Equine recurrent uveitis (ERU) is a leading cause of vision loss in horses. Objective: To assess the prognosis and impact of ERU on affected horses and their owners by evaluating the signalment, treatment and outcome (including the loss of use, vision assessment and economic loss). Methods: Retrospective impact study. Methods: Medical records of horses presenting to the North Carolina State University Veterinary Health Complex (NCSU-VHC) with ERU between 1999 and 2014 were reviewed. Signalment, clinical signs, ophthalmic examination findings, treatments and outcomes were evaluated. Owner quest...
Barrachina L, Remacha AR, Romero A, Vitoria A, Albareda J, Prades M, Roca M, Zaragoza P, Vázquez FJ, Rodellar C.This study aimed at assessing the effectiveness and safety of repeated administrations of allogeneic bone marrow-derived mesenchymal stem cells (BM-MSCs) primed with tumor necrosis factor (TNF)-α and interferon-γ in an equine model of chemically-induced osteoarthritis. Arthritis was induced in both radio-carpal (RC)-joints by amphotericin-B in 18 ponies, divided into three groups depending on the treatment injected: MSC-naïve (n = 7), MSC-primed (n = 7) and control (n = 4). The study consisted of two phases and used one RC-joint of each animal in each phase, with four months tim...
Fielding CL, Higgins JK, Higgins JC, McIntosh S, Scott E, Giannitti F, Mete A, Pusterla N.Equine coronavirus (ECoV) is associated with clinical disease in adult horses. Outbreaks are associated with a low case fatality rate and a small number of animals with signs of encephalopathic disease are described. Objective: The aim of this study is to describe the epidemiological and clinical features of two outbreaks of ECoV infection that were associated with an high case fatality rate. Methods: 14 miniature horses and 1 miniature donkey testing fecal positive for ECoV from two related disease outbreaks. Methods: Retrospective study describing the epidemiological findings, clinicopatholo...
Pollitt CC.Thirty-two dorsal, mid-hoof wall, lamellar sections from 8 Standardbred horses, humanely killed 48 h after the administration of an alimentary carbohydrate overload, were sectioned and examined by light microscopy. Sections were stained with the connective tissue and basement membrane stains periodic acid-Schiff (PAS), Azan and periodic acid silver methanamine (PASM) and with routine haematoxylin and eosin (H&E). Lesions of the epidermal lamellae, attributable to laminitis, were graded in order of increasing severity from Grade N (normal), Grade 1 (mild), Grade 2 (moderate) to Grade 3 (severe ...
Broeckx SY, Martens AM, Bertone AL, Van Brantegem L, Duchateau L, Van Hecke L, Dumoulin M, Oosterlinck M, Chiers K, Hussein H, Pille F, Spaas JH.There is a need to improve therapies for osteoarthritis in horses. Objective: To assess the efficacy of equine allogeneic chondrogenic-induced mesenchymal stem cells combined with equine allogeneic plasma as a novel therapy for osteoarthritis in horses. Methods: Randomised, double-blinded, placebo-controlled experiment. Methods: In 12 healthy horses, osteoarthritis was induced in the metacarpophalangeal joint using an osteochondral fragment-groove model. Five weeks after surgery, horses were randomly assigned to either an intra-articular injection with chondrogenic-induced mesenchymal stem cel...
Dugdale AH, Curtis GC, Harris PA, Argo CM.Evaluation of equine body fat content is important for nutritional and clinical purposes. However, our understanding of total body fat and its regional distribution in the body is sparse. Currently, body fat evaluation relies on the subjective assessment of body condition score (BCS), which has never been validated against 'gold standard' chemical analysis or dissection measurements in ponies. Objective: To define the relationships between subjective (BCS), objective (morphometric) indices of body fat and 'gold standard' measurements of actual body composition. Objective: BCS and morphometry o...
Boden LA, Anderson GA, Charles JA, Morgan KL, Morton JM, Parkin TD, Clarke AF, Slocombe RF.Research into risk factors specific for fatality in flat racing should be focused at a regional level as the risk factors may differ among countries and even regions within countries. Objective: To identify risk factors for fatality of Thoroughbred racehorses in flat starts on all racecourses in Victoria, Australia between 1989 and 2004. Methods: Fatalities comprised all horses that died during or immediately after a flat race or official flat trial, and all horses that were subjected to euthanasia within 24 h of an event in which an injury was sustained. The retrospective study involved 283 c...
Rioja-Lang FC, Connor M, Bacon H, Dwyer CM.Equine welfare issues are receiving increasing attention in the UK, but welfare problems can arise from a wide range of causes. In order to identify the most important welfare concerns for horses, we used a Delphi method with 19 equine welfare experts. An initial list of 84 equine welfare issues was generated using an online discussion board and NVivo thematic analysis. Subsequently, experts ranked these welfare issues for perceived prevalence, severity and duration of suffering associated with each issue on a 6-point Likert scale. All issues with a mean score of 3 or above ( = 37) were includ...
Pihl TH, Nielsen MK, Olsen SN, Leifsson PS, Jacobsen S.Strongylus vulgaris is re-emerging in horses kept under surveillance-based parasite control regimens. Information on nonstrangulating intestinal infarction associated with S. vulgaris is needed to improve recognition of the condition. Objective: To describe the typical clinical presentation, laboratory findings, gross pathology, treatment and outcome of horses with nonstrangulating intestinal infarction. Methods: Retrospective case series. Methods: Nonstrangluating intestinal infarction was diagnosed in 30 horses with a localised intestinal infarction with concurrent signs of S. vulgaris mig...
van Zyl A, Daniel J, Wayne J, McCowan C, Malik R, Jelfs P, Lavender CJ, Fyfe JA.Two horses were diagnosed as having Mycobacterium ulcerans infections. The first was a 21-year-old Quarterhorse-cross mare living in Mallacoota (a coastal town near the border of New South Wales and Victoria, Australia) that presented with lichenification, hair-loss and oedema on a fetlock, which subsequently ulcerated, as well as a non-healing ulcer on the wither. The second horse was a 32 year-old Standardbred gelding from Nicholson, near Bairnsdale, Victoria, that had an ulcerated lesion on its caudal thigh. Histologically, there were characteristic changes seen with M. ulcerans infections ...
de Heus P, Kolodziejek J, Camp JV, Dimmel K, Bagó Z, Hubálek Z, van den Hoven R, Cavalleri JV, Nowotny N.We report details of the first seven equine cases of confirmed West Nile neuroinvasive disease in Austria. The cases presented during summer and autumn of 2016 (n = 2), 2017 (n = 3) and 2018 (n = 2). All horses showed gait abnormalities and 6 of 7 horses exhibited fasciculations and/or tremors, and we provide video recordings of these. Three horses also showed cranial nerve involvement. Following rapid improvement, three horses were discharged. Four horses were euthanized due to the severity of clinical signs and subjected to neuropathological examination. West Nile virus (WNV) lineage 2...
Miller MA, Moore GE, Bertin FR, Kritchevsky JE.Postmortem findings in 241 equids admitted to a teaching hospital that were at least 15 years old at autopsy were reviewed (1) to determine disease prevalence, (2) to compare the cause of death (or euthanasia) in equids 15 to 19 years of age (n = 116) with that in equids ≥20 years of age (n = 125), and (3) to catalog coexisting lesions in equids with pituitary pars intermedia dysfunction (PPID). Breed and sex were evenly distributed between the age groups. Death or euthanasia was attributed to disease of the digestive system (41.5%), pituitary gland (12.9%), locomotor system (10.0%), nervous...
Conze P, van Schie HT, van Weeren R, Staszyk C, Conrad S, Skutella T, Hopster K, Rohn K, Stadler P, Geburek F.To investigate whether autologous adipose tissue-derived mesenchymal stem cells (AT-MSCs) treatment of tendon lesions increases neovascularization during tendon healing. Methods: A standardized surgical model was used to create lesions in both front limb superficial digital flexor tendons (SDFTs) of nine horses. Either AT-MSCs or control substance was injected intralesionally 2 weeks post-surgery. Color Doppler ultrasonography of SDFTs was performed at regular intervals. Horses were euthanized 22 weeks post-treatment and SDFTs were harvested for histology. Results: The color Doppler ultrasonog...
James FM, Engiles JB, Beech J.A 12-year-old Thoroughbred was examined because of signs of depression, neck stiffness, and poor performance. Results: Physical examination revealed that the horse was dull, appeared depressed, was reluctant to raise its neck and head above a horizontal plane, and had a temperature of 38.5°C (101.3°F). No radiographic or scintigraphic abnormalities of the neck were found; however, high plasma fibrinogen concentration and relative lymphopenia were identified and the horse was seropositive for antibodies against Borrelia burgdorferi. Analysis of CSF revealed neutrophilic inflammation, and resu...
Jones E, Viñuela-Fernandez I, Eager RA, Delaney A, Anderson H, Patel A, Robertson DC, Allchorne A, Sirinathsinghji EC, Milne EM, MacIntyre N....Laminitis is a common debilitating disease in horses that involves painful disruption of the lamellar dermo-epidermal junction within the hoof. This condition is often refractory to conventional anti-inflammatory analgesia and results in unremitting pain, which in severe cases requires euthanasia. The mechanisms underlying pain in laminitis were investigated using quantification of behavioural pain indicators in conjunction with histological studies of peripheral nerves innervating the hoof. Laminitic horses displayed consistently altered or abnormal behaviours such as increased forelimb lifti...
Estberg L, Stover SM, Gardner IA, Johnson BJ, Case JT, Ardans A, Read DH, Anderson ML, Barr BC, Daft BM, Kinde H, Moore J, Stoltz J, Woods LW.To characterize and contrast data from Thoroughbreds that incurred a fatal musculoskeletal injury (FMI; injury resulting in death or euthanasia) during racing or training and data from all California race entrants during a 9-month period in 1991. Methods: Case-control study. Methods: Thoroughbreds that incurred a FMI during racing or training at a California race-meet and all California race entrants from January through June and October through December 1991. Methods: Age and sex were compared with chi 2 and Fisher's exact tests among horses fatally injured while racing and training. A log-li...
Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL.Lateral condylar fractures of the third metacarpus/metatarsus are the most common cause of equine fatality on UK racecourses. Identification of risk factors for such injuries and the subsequent implementation of intervention strategies could significantly reduce the total number of racecourse fatalities. Objective: To identify horse-, race- and course-level risk factors for fatal lateral condylar fracture in Thoroughbreds on UK racecourses. Methods: Case-control study designs were used. Case horses were defined as those that were subjected to euthanasia having sustained an irreparable lateral ...
Wong DM, Belgrave RL, Williams KJ, Del Piero F, Alcott CJ, Bolin SR, Marr CM, Nolen-Walston R, Myers RK, Wilkins PA.5 horses were evaluated because of decreased appetite, weight loss, fever, cough, tachypnea, and respiratory distress. Results: Tachycardia, tachypnea, increased respiratory effort, lethargy, fever, poor body condition, and nasal discharge were detected in various combinations on initial physical examination. Evaluation of the lower portion of the respiratory tract via radiography and ultrasonography revealed a severe nodular interstitial pattern. Histologic examination of lung tissue revealed interstitial expansion of alveolar parenchyma with collagen, intraluminal accumulation of neutrophils...
Egenvall A, Penell JC, Bonnett BN, Olson P, Pringle J.The aim of this study was to evaluate the potential usefulness of the database maintained by the Swedish insurance company Agria for providing mortality statistics on Swedish horses. Mortality statistics (incidence rates and survival) were calculated, both crudely and stratified by sex, age, breed, breed group and diagnosis, for the horses with complete life insurance, which covers most health problems. The total mortality was 415 (95 per cent confidence interval [CI] 399 to 432) deaths per 10,000 horse-years at risk, and the diagnostic mortality, including only deaths with an assigned diagnos...
van Maanen C, Sloet van Oldruitenborgh-Oosterbaan MM, Damen EA, Derksen AG.An outbreak of neurological disease caused by EHV-1 infection is described with emphasis on diagnosis and prognosis for recumbent horses. In April 1995, an outbreak of the neurological form of Equine herpesvirus type 1 (EHV-1) occurred in a well-managed riding school with 41 horses: 34 horses showed a temperature spike and 20 some degree of neurological signs, of which 10 were nursed intensively in the indoor arena of the riding school for 3 to 20 days, 8 having to be maintained in slings for 2-18 days, while 9 needed bladder catheterisation b.i.d. for 2-16 days. Within the first 3 days, one h...
Davis JL, Salmon JH, Papich MG.To determine pharmacokinetics, safety, and penetration into interstitial fluid (ISF), polymorphonuclear leukocytes (PMNLs), and aqueous humor of doxycycline after oral administration of single and multiple doses in horses. Methods: 6 adult horses. Methods: The effect of feeding on drug absorption was determined. Plasma samples were obtained after administration of single or multiple doses of doxycycline (20 mg/kg) via nasogastric tube. Additionally, ISF, PMNLs, and aqueous humor samples were obtained after the final administration. Horses were monitored for adverse reactions. Results: Feeding ...
Sweeney CR, Holcombe SJ, Barningham SC, Beech J.Frequency of aerobic and anaerobic isolates in 327 aspirates and in 123 pleural fluid samples from 327 horses with pneumonia or pleuropneumonia and antimicrobial susceptibility patterns of the aerobes were reported. Of the 327 horses, 75% survived, 20% were euthanatized, and 5% died. Tracheobronchial aspirates or pleural fluid specimens from 25 of the horses did not yield growth. Of the remaining 302 horses, 221 had only aerobic organisms isolated, whereas only anaerobes were isolated from 6 of the 302 horses. The remaining 75 horses had mixed aerobic and anaerobic bacterial infections. The su...
Ireland JL, Clegg PD, McGowan CM, Platt L, Pinchbeck GL.Geriatric horses (aged≥15 years) now represent a substantial proportion of the equine population, yet mortality rates for aged horses in the UK have not previously been described. Although post-mortem studies have provided some data regarding specific causes of death, "old age" is a common owner-reported reason for euthanasia of adult horses, indicating further elucidation of reasons for death or euthanasia is required for the geriatric equine population. The objective of this cohort study was to describe mortality rates, causes of death or euthanasia and factors associated with mortality in...
