Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Goodman LB, Wimer C, Dubovi EJ, Gold C, Wagner B.Equine herpesvirus 1 (EHV-1) induces a variety of disease manifestations, including respiratory disease, abortions, and myeloencephalopathy. Several vaccines are commercially available but could not previously be distinguished by serologic testing from infection with EHV-1 (or the closely related EHV-4). Currently available vaccines are not reliably protective against the severe manifestations of the disease, including fatal myeloencephalopathy. We determined immunological parameters that can differentiate vaccinated from previously infected animals by comparing humoral and cellular EHV-1-spec...
Evans PM, Armour MD, Dubielzig RR. To describe the gross and histopathological ocular findings in a horse following suspected lightning injury. Methods: The eyes of a 2-year-old thoroughbred gelding were clinically and histopathologically evaluated following a severe lightning storm following euthanasia because of visual impairment. Results: Severe corneal edema and hydrops were noted clinically oculus dexter. Indirect ophthalmoscopy revealed bilateral symmetrical raised hyporeflective peripapillary geographic lesions. Histopathologic evaluation revealed corneal edema in the right eye with normal corneal endothelium...
Cissell DD, Wisner ER, Textor J, Mohr FC, Scrivani PV, Théon AP.The computed tomography (CT) features of tumors involving the nasal cavity and/or paranasal sinuses of 15 horses were reviewed. The 15 tumors included five neuroendocrine tumors/neuroblastomas, two undifferentiated carcinomas, two myxosarcomas, and one each of nasal adenocarcinoma, hemangiosarcoma, chondroblastic osteosarcoma, anaplastic sarcoma, myxoma, and ossifying fibroma. All tumors except the ossifying fibroma were iso- or hypoattenuating relative to masseter muscle. Thirteen of the fifteen tumors exhibited moderate or marked osteolysis of adjacent cortical bone and 14/15 were characteri...
Zhang L, Franchini M, Wehrli Eser M, Jackson EK, Dip R.Several reports have suggested a role for adenosine in the pathogenesis of chronic airway conditions and this has led to new therapeutic strategies to limit airway inflammation. In this study, detectable levels of adenosine in bronchoalveolar lavage (BAL) samples from 11 horses with non-infectious lower-airway inflammation and 14 healthy controls are reported, with significantly higher values in horses with airway inflammation. Although these increased levels did not correlate with changes in neutrophil percentage in BAL, a positive association between adenosine levels and signs of lower airwa...
de Laat MA, Kyaw-Tanner MT, Sillence MN, McGowan CM, Pollitt CC.Advanced glycation endproducts (AGEs) have been implicated in the pathogenesis of cancer, inflammatory conditions and diabetic complications. An interaction of AGEs with their receptor (RAGE) results in increased release of pro-inflammatory cytokines and reactive oxygen species (ROS), causing damage to susceptible tissues. Laminitis, a debilitating foot condition of horses, occurs in association with endocrine dysfunction and the potential involvement of AGE and RAGE in the pathogenesis of the disease has not been previously investigated. Glucose transport in lamellar tissue is thought to be l...
Yao S, Qi J, Liu J, Chen R, Pan X, Li X, Gao F, Xia C.In order to clarify the structure and the peptide-presentation characteristics of the equine major histocompatibility complex (MHC) class I molecule, a complex of equine MHC class I molecule (ELA-A1 haplotype, 7-6 allele) with mouse β(2)-microglobulin and the cytotoxic T lymphocyte (CTL) epitope Env-RW12 (RVEDVTNTAEYW) derived from equine infectious anaemia virus (EIAV) envelope protein (residues 195-206) was refolded and crystallized. The crystal, which belonged to space group P2(1), diffracted to 2.3 Å resolution and had unit-cell parameters a = 82.5, b = 71.4, c = 99.8 Å, β = 102.9°. T...
Grandgeorge M, Hausberger M.Humans have a long history of relationship with domestic animals and nowadays pets often act as "social substitutes" through bonding. There is some evidence that pet presence at home may induce well being in people and the development of social skills in children. Animal assisted therapies aim at developing these skills in patients on the basis of human animal interactions. Experimental data obtained on animal models suggest that this is indeed a promising line. There is however a lack of clear scientific data that would help defines what the most appropriate procedures or species may be. Impr...
Scacchia M, Cammà C, Di Francesco G, Di Provvido A, Giunta R, Luciani M, Marino AM, Pascucci I, Caporale V.In May 2011, dourine was reported in Italy following the declaration of a positive result observed in a stallion undergoing routine testing for stud purposes. Clinical signs, anatomo-histopathological findings and laboratory results that resulted in the confirmation of diagnosis of dourine in a clinically affected mare, which was the likely source of infection in the stallion, are described.
Roth JA.Veterinary vaccines have had, and continue to have, a major role in protecting animal health and public health, reducing animal suffering, enabling efficient production of food animals to feed the burgeoning human population, and greatly reducing the need for antibiotics to treat food and companion animals. Prominent examples include rabies vaccines and rinderpest vaccines. Rabies vaccines for domestic animals and wildlife have nearly eliminated human rabies in developed countries. Thanks to the Global Rinderpest Eradication Program which involves vaccination, trade restrictions, and surveilla...
Wijnberg ID, Owczarek-Lipska M, Sacchetto R, Mascarello F, Pascoli F, Grünberg W, van der Kolk JH, Drögemüller C.A 7-month-old New Forest foal presented for episodes of recumbency and stiffness with myotonic discharges on electromyography. The observed phenotype resembled congenital myotonia caused by CLCN1 mutations in goats and humans. Mutation of the CLCN1 gene was considered as possible cause and mutation analysis was performed. The affected foal was homozygous for a missense mutation (c.1775A>C, p.D592A) located in a well conserved domain of the CLCN1 gene. The mutation showed a recessive mode of inheritance within the reported pony family. Therefore, this CLCN1 polymorphism is considered to be a...
Aleman M, Pickles KJ, Simonek G, Madigan JE.Trigeminal neuralgia or neuropathic pain has been regarded as a putative cause of idiopathic headshaking in horses. Equine herpesvirus-1 (EHV-1) infection and resultant postherpetic pain have been suggested as a possible cause of such neuropathic pain. Objective: To determine the presence of EHV-1 in the trigeminal ganglia of horses with idiopathic headshaking. Methods: Nineteen horses: control (n = 11, 9 geldings, 2 mares, median age 11 years) and headshaking (n = 8, all geldings, median age 11.5 years) horses were sourced from the equine research herd and caseload at the Veterinary Medical T...
Jacob JC, Haag KT, Santos GO, Oliveira JP, Gastal MO, Gastal EL.In the present study, 809 uterine flushes and 454 embryo transfers performed in mares over a 4-yr interval were examined to evaluate the effects of: (1) the day of embryo collection on recovery rates; (2) the degree of synchrony between donor and recipient mares on pregnancy rates; (3) the recipient day post ovulation on pregnancy rates; and (4) the age of the embryo at recovery on pregnancy rates at 60 days. Uterine flushes were performed on Days 6, 7, 8, 9, and 10 (Day 0 = ovulation) and embryos were transferred to recipients with degrees of synchrony varying between +1 to -6 (recipient ovul...
Costa MF, Ronchi FA, Ivanow A, Carmona AK, Casarini D, Slocombe RF.Exercise-induced pulmonary haemorrhage has an impact on racehorse performance. Although endoscopic diagnosis (with or without the aid of bronchoalveolar lavage) is considered to be the standard diagnostic method for this condition, the use of biomarkers that could aid in quantifying risk and severity of the condition would represent an advance in equine sport medicine. This preliminary research investigated the use of angiotensin-converting enzyme (ACE) activity in plasma of racehorses and demonstrated that ACE activity is increased in horses with higher degrees of haemorrhage and is a promisi...
Yue XP, Qin F, Campana MG, Liu DH, Mao CC, Wang XB, Lan XY, Chen H, Lei CZ.Previous mitochondrial DNA (mtDNA) D-loop and microsatellite studies have shown that Chinese horses have multiple maternal origins and high genetic diversity. To better characterize maternal genetic origins and diversity of Chinese domestic horses, we conducted a comprehensive analysis of 407 complete 1140 bp sequences of the horse mitochondrially encoded cytochrome b (CYTB) gene, including 323 horses from 13 Chinese indigenous breeds and 84 reference sequences from GenBank. A total of 114 haplotypes were identified, of which 73 appeared among the 13 Chinese horse breeds. The high mitochondria...
Matthijnssens J, Miño S, Papp H, Potgieter C, Novo L, Heylen E, Zeller M, Garaicoechea L, Badaracco A, Lengyel G, Kisfali P, Cullinane A, Collins PJ....In this study, the complete genome sequences of seven equine group A rotavirus (RVA) strains (RVA/Horse-tc/GBR/L338/1991/G13P[18], RVA/Horse-wt/IRL/03V04954/2003/G3P[12] and RVA/Horse-wt/IRL/04V2024/2004/G14P[12] from Europe; RVA/Horse-wt/ARG/E30/1993/G3P[12], RVA/Horse-wt/ARG/E403/2006/G14P[12] and RVA/Horse-wt/ARG/E4040/2008/G14P[12] from Argentina; and RVA/Horse-wt/ZAF/EqRV-SA1/2006/G14P[12] from South Africa) were determined. Multiple novel genotypes were identified and genotype numbers were assigned by the Rotavirus Classification Working Group: R9 (VP1), C9 (VP2), N9 (NSP2), T12 (NSP3), ...
Pitzer JB, Kaufman PE, Geden CJ, Hogsette JA.The ability of Spalangia cameroni Perkins, Spalangia endius Walker, and Muscidifurax raptorellus Kogan and Legner to locate and attack stable fly hosts was evaluated under laboratory conditions. Postfeeding third-instar stable fly larvae were released and allowed to pupate in two arena types: large 4.8 liter chambers containing a field-collected, soiled equine bedding substrate; or 120-ml plastic cups containing wood chips. At the time of fly pupariation, parasitoids were released and permitted 72 h to locate and attack hosts. On average, parasitism rates of freely accessible stable fly pupae ...
Witt MC, Bollwein H, Probst J, Baackmann C, Squires EL, Sieme H.The aim of the present study was to investigate the effects of a gonadotropin treatment to induce superovulation on ovarian and uterine blood flow and its relationship with steroid hormone levels and ovarian response in mares, using color Doppler sonography. Each of six mares were examined sonographically in five cycles for 3 d (t1 to t3) during the follicular development phase (FDP) beginning at a follicle size of ≥ 22 mm, and for 4 d (D-4 to D-1; D0 = Ovulation) in the preovulatory phase (POP). After each examination, total estrogens (E(tot)) and progesterone (P(4)) levels were determined ...
Castejón-Riber C, Muñoz A, Trigo P, Riber C, Santisteban R, Castejón F.Significant differences exist in the respiratory adaptation to exercise in different equine breeds. This research describes the ergoespirometric response to exercise of Andalusian (AN) and Arabian (A) horses, both selected according to morphological criteria. Thirteen untrained male horses (6 AN and 7 A) performed a treadmill exercise test (TET) with a slope of 6%, with workloads starting from 5 m/s and increasing 1 m/s every 3 min until the horses were not able to keep the required velocity. Tidal volume (TV), respiratory rate, minute ventilation (VE), oxygen uptake (VO2), carbon dioxide prod...
Tennent-Brown BS.Blood lactate concentration can be easily measured by practitioners using inexpensive point-of-care meters. Anaerobic tissue metabolism resulting from inadequate oxygen delivery (DO2) is the most important cause of an increase in blood lactate concentration in equine patients. However,hyperlactatemia also occurs under conditions of apparently adequate DO2, usually in association with sepsis and an intense inflammatory reaction. Numerous mechanisms have been proposed for aerobic hyperlactatemia, including increased Na+/K+-ATPase activity in response to inflammatory mediators; inhibition of pyru...
Bliss SB, Voge JL, Hayden SS, Teague SR, Brinsko SP, Love CC, Blanchard TL, Varner DD.The objective was to determine if decreased cushion-fluid volume and increased sperm number during centrifugation, or if sperm concentration of extended semen following centrifugation, affected stallion sperm quality. Three ejaculates from each of three stallions were subjected to cushioned centrifugation (1,000g for 20 min). Cushion-fluid volume was set at 1 or 3.5 ml, and sperm number per centrifuge tube was set 1 billion or 3 billion. Following centrifugation, sperm pellets were resuspended in semen extender containing 20% seminal plasma (v/v) with sperm concentrations of 25 or 250 million/...
Ginther OJ.Recent findings on the luteolytic process in mares are reviewed and differences from other farm species are noted. It is well known that the luteolysin, PGF2α (PGF), is secreted from the endometrium in the absence of pregnancy in farm animal species. But PGF is a potent chemical and safeguards have evolved so that only the corpus luteum (CL) is affected. The safeguards include a short PGF half-life and secretion in two or three pulses per day. In mares, endogenous PGF travels from the uterus to the CL through the systemic circulation, but the luteal-cell membranes are highly efficient in capt...
Dicken M, Gee EK, Rogers CW, Mayhew IG.To examine the gestation lengths and occurrence of daytime foaling of Standardbred mares foaling outdoors at stud farms in Southland, New Zealand (latitude 45˚S). Methods: Data were collected prospectively at two commercial Standardbred stud farms (Farms A and B), during the 2008/9 and 2009/10 breeding seasons (October to February). For each foaling, the identity of the mare, date and time of foaling, gender of foal, time the mare passed the fetal membranes, time the foal stood, and foaling problems including dystocias, were recorded. The effect of farm, season, gender of foal, month of artif...
Becker AC, Stock KF, Distl O.Detailed movement evaluations of warmblood foals and mares were performed in connection with regular breeding events of the Oldenburg horse breeding societies in 2009 and 2010. Unfavourable movement characteristics considered indicative for impaired balance were noted by a special judge (SJ) and the regular judges of the breeding events (RJ) and served as the basis for definition of new movement traits. Detailed movement information on 3374 foals and 2844 mares showed that more severe findings like irregular motion pattern in hind legs or irregularity in general motion pattern occurred only sp...
Archer RM, Gordon SJ, Carslake HB, Collett MG.A 3-month-old female Warmblood foal was presented after displaying signs of colic with pyrexia for 5 days. Results: The foal continued to show signs of colic, frequently passed urine, and was pyrexic with an elevated white blood cell count. The umbilical stalk was thickened but there was no evidence of purulent material. Exploratory laparotomy revealed an enlarged left umbilical artery remnant tightly adhered to the bladder wall. The left umbilical artery continued to an aneurysm involving the distal aorta. The foal was subject to euthanasia and post-mortem examination confirmed a spherical ao...
Kotoyori Y, Yokoo N, Ito K, Murase H, Sato F, Korosue K, Nambo Y.The objective was to assess the optimal procedure for real-time, three-dimensional (3D) ultrasound (US) imaging for assessing the equine fetus during the first half of gestation and the possibility of using 3D US imaging of the equine fetus in clinical applications. Seventeen pregnant mares were examined by 3D US between Days 35 and 180 of gestation. Abdominal and endo-vaginal real-time 3D transducers used in human medicine were used for transrectal and transvaginal examinations, respectively. Images were recorded by both 3D stationary and real-time movies. In a comparison of four methods, tra...
Galvão A, Skarzynski DJ, Szóstek A, Silva E, Tramontano A, Mollo A, Mateus L, Ferreira-Dias G.Knowledge on the regulation of corpus luteum (CL) function in the mare is scarce. In this study, the presence of cytokines tumor necrosis factor alpha (TNF) and interferon gamma (IFNG), and their receptors (TNFRI, TNFRII and IFNRI), was investigated in equine CL throughout the luteal phase. The effects of TNF and IFNG on secretory function and viability of luteal cells were defined in vitro. Cytokine ligands and receptors were present in steroidogenic and endothelial cells. Protein expression for TNF was greater in mid-phase and regressing CL, while TNFRI was increased in regressing CL and TNF...
Catt CJ, Schuurman W, Sengers BG, van Weeren PR, Dhert WJ, Please CP, Malda J.In the field of cartilage tissue engineering, filter cultures are a frequently used three-dimensional differentiation model. However, understanding of the governing processes of in vitro growth and development of tissue in these models is limited. Therefore, this study aimed to further characterise these processes by means of an approach combining both experimental and applied mathematical methods. A mathematical model was constructed, consisting of partial differential equations predicting the distribution of cells and glycosaminoglycans (GAGs), as well as the overall thickness of the tissue....
Marsh GA, Haining J, Hancock TJ, Robinson R, Foord AJ, Barr JA, Riddell S, Heine HG, White JR, Crameri G, Field HE, Wang LF, Middleton D.Hendra virus (HeV) is a highly pathogenic zoonotic paramyxovirus harbored by Australian flying foxes with sporadic spillovers directly to horses. Although the mode and critical control points of HeV spillover to horses from flying foxes, and the risk for transmission from infected horses to other horses and humans, are poorly understood, we successfully established systemic HeV disease in 3 horses exposed to Hendra virus/Australia/Horse/2008/Redlands by the oronasal route, a plausible route for natural infection. In 2 of the 3 animals, HeV RNA was detected continually in nasal swabs from as ea...
Sekkin S, Gokbulut C, Kum C, Karademir U.This study was designed to investigate the plasma disposition and systemic availability of enrofloxacin (ENR) following intramuscular and intravenous administrations. Six donkeys (Equus asinus) were used in this study. The animals were allocated into two groups (intramuscular and intravenous groups). After a 2-week washout period, the experiment was repeated with the groups reversed according to a two-phase crossover design. In phase I, group I received intravenously the commercially available injectable solution of ENR at the dose of 5 mg/kg and group II received intramuscularly the same ENR ...
McConnell EJ, Rioja E, Bester L, Sanz MG, Fosgate GT, Saulez MN.Alterations in cerebral haemodynamics may contribute to perianaesthetic complications in horses. Near-infrared spectroscopy (NIRS) is frequently used intraoperatively in man to provide information regarding cerebral perfusion. Objective: To determine whether NIRS can identify trends in regional cerebral oxygen saturation (rSO2) in horses and whether there is a correlation between rSO2 and venous oxygen tensions. Methods: A cerebral oximeter sensor recorded rSO2 from the dorsal sagittal sinus of 6 healthy horses. Values for rSO2, arterial and venous oxygen and carbon dioxide tensions (PaO2, PvO...
Cox S, Sommardahl C, Fortner C, Davis R, Bergman J, Doherty T.Non-steroidal anti-inflammatory drugs are inhibitors of cyclooxygenase (COX) in tissues and used as therapeutic agents in different species. Grapiprant, a member of the piprant class of compounds, antagonizes prostaglandin receptors. It is a highly selective EP4 prostaglandin E receptor inhibitor, thereby limiting the potential for adverse effects caused by wider COX inhibition. The objectives of this study were to determine if the approved canine dose would result in measurable concentrations in horses, and to validate a chromatographic method of analysis for grapiprant in urine and plasma. M...
This study was conducted to assess the presence of West Nile virus (WNV) in Kosovo by serological testing of apparently healthy local horses and free-range chicken, and it attempted to detect viral nucleic acid in birds and mosquitoes. Between January 2018 and June 2019, 260 equine serum samples were collected, additionally 580 adult mosquitoes (53 pools) were grouped in for genera, including spp. (226 individuals; 26 pools), spp. (136 individuals; 16 pools), spp. (184 individuals; 7 pools), and spp. (34 individuals; 4 pools). Fifty domestic birds and 51 wild birds were collected from diff...
Krause JB, McKenzie HC.Adequate nutritional support of sick foals in critical care is an important aspect of treatment. When enteral feeding is contraindicated, parenteral nutrition (PN) provides a source of energy and protein. However, no study has critically assessed the use of PN in a large group of foals. Objective: The administration of PN to clinically ill foals was examined retrospectively to determine the effects of PN formulation and variables on the incidence of PN-associated complications and outcome. Objective: There was no effect of PN formula on 1) the occurrence or type of complications; 2) of PN form...
Lee CD, Maxwell LK.In most species, large variations in body size necessitate dose adjustments based on an allometric function of body weight. Despite the substantial disparity in body size between miniature horses and light-breed horses, there are no studies investigating appropriate dosing of any veterinary drug in miniature horses. The purpose of this study was to determine whether miniature horses should receive a different dosage of flunixin meglumine than that used typically in light-breed horses. A standard dose of flunixin meglumine was administered intravenously to eight horses of each breed, and three-...
Kikuchi N, Blakeslee JR, Hiramune T.Plasmid profiles of Klebsiella pneumoniae isolated from horses were examined. Thirty-nine strains of K. pneumoniae capsular type 1 (K1) isolated from cervical swabs of mares suffering from metritis, and from semen of stallions showed similar plasmid profile patterns, and all strains possessed a 125 megadaltons (Md) plasmid. There was no difference in plasmid profiles between the heavily-encapsulated and the less heavily-encapsulated strains of K. pneumoniae K1. Non-capsulated variants derived from the strains of K1 showed the same plasmid profile pattern as the parent strains. Plasmid profiles...
Németh F, Back W.The walking cast was used to repair 46 fractures of long bones (distal radius and tibia, metacarpus and metatarsus) and 10 fractures of first phalanx of 35 horses and 21 ponies. The walking cast proved to be highly effective. Even heavily comminuted and 'hopeless' fractures, which could not be treated with osteosynthesis, were treated successfully, because the weight of the animal, a common failure factor in large animal orthopaedics, was relieved from the injured leg. Immediate full weight bearing was possible post operatively. In five cases the walking cast was used in combination with osteo...
Shubitowski DM, Venta PJ, Douglass CL, Zhou RX, Ewart SL.The continued discovery of polymorphisms in the equine genome will be important for future studies using genomic screens and fine mapping for the identification of disease genes. Segments of 50 equine genes were examined for variability in 10 different horse breeds using a pool-and-sequence method. We identified 11 single nucleotide polymorphisms (SNPs) in 9380 bp of sequenced exon, and 25 SNPs, six microsatellites, and one insertion/deletion in 16961 bp of sequenced intron. Of all genes studied 52% contained at least one polymorphism, and polymorphisms were found at an overall rate of 1/613 b...
O'Leary JM, Barnett TP, Parkin TD, Dixon PM, Barakzai SZ.Although equine motorised dental instruments are widely used, there is limited information on their thermal effect on teeth. The recently described variation in subocclusal secondary dentine depth overlying individual pulp horns may affect heat transmission to the underlying pulps. Objective: This study compared the effect of 3 different equine motorised dental instruments on the pulpar temperature of equine cheek teeth with and without the use of water cooling. It also evaluated the effect of subocclusal secondary dentine thickness on pulpar temperature changes. Methods: A thermocouple probe ...
Tozaki T, Ohnuma A, Hamilton NA, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI.Gene doping is prohibited for fair competition in human and horse sports. One style of gene doping is the administration of an exogeneous gene, called a transgene, to postnatal humans and horses. Although many transgene detection methods based on quantitative polymerase chain reaction (PCR), including real-time PCR and digital PCR, have been recently developed, it remains difficult to reliably detect low-copy transgenes. In this study, we developed and validated a nested digital PCR method to specifically detect low-copy transgenes. The nested digital PCR consists of (1) preamplification using...
Svendsen CK, Hjortkjaer RK, Hesselholt M.42 horses were examined. The physical signs with relation to circulatory insufficiency and the abdominal disease were registered following a two-phased examination procedure. Great prognostic value was found in the degree of circulatory insufficiency judged by pulse rate and character, filling of the jugular vein, skin temperature, colour of mucous membranes, capillary refill time, sweating, depression, skin turgor and degree of enophthalmus. In making a causal diagnosis the abdomen was examined for shape, tenderness, peristaltic sounds, gastric dilation by siphoning, abnormal rectal findings ...
Bowen IM, Marr CM, Chester AH, Wheeler-Jones CP, Elliott J.The equine aortic valve is subject to non-inflammatory degenerative changes, associated with aortic valvular regurgitation (AR). This disease shares pathological and epidemiological features with AR in humans, and may serve as a useful model to study in-vitro functional responses associated with aging and disease. The study aim was to determine the contractile properties of the normal equine aortic valve. Methods: The contractile responses of equine aortic valves to angiotensin II, the thromboxane-mimetic U44069, endothelin-1, 5-hydroxytryptamine and the alpha-adrenoceptor agonists medetomidin...
McMullen RJ, Utter ME.The purpose of this review is to discuss the evolution of equine cataract surgery over the past 50 years to its current stage. Equine cataract surgery is performed similarly compared with the techniques used in human ophthalmology and in other veterinary species. However, enough differences exist to make surgical lens removal and intraocular lens implantation in the horse an intrinsically unique endeavour. Due to the size of the adult equine globe, the introduction of species-specific instrumentation has provided the cornerstone to many of the changes made regarding surgical technique over the...
McCutcheon LJ, Geor RJ.The objectives of this study were to: 1) determine incremental and total sweat fluid and ion losses during and following (a) exercise training and (b) a treadmill Speed and Endurance exercise test (SEET) which simulated running speeds and distances required for each phase of an Olympic level (CCI****) 3-day-event in cool and hot ambient conditions and 2) determine the requirement for ion supplementation based on the calculated ion losses associated with these activities. Six exercise-trained Thoroughbred horses completed 2 weeks of exercise training in each of 2 ambient conditions: cool, dry (...
York CA, Schulte BA.Maintaining a dominant position in a hierarchy requires energetically expensive aggressive displays and physical exertion. Lab based winner-loser studies, often conducted with individuals from non-social species, have shown that subordinates have higher stress hormone levels than dominant individuals. However, in wild studies on cooperative breeders, displays of aggression used to maintain dominance status are associated with elevated stress hormone levels. The effect of reproductive state on dominance and stress has not been addressed within either of these situations. The purpose of this stu...
Morrell JM, Geraghty RM.A method of removing equine arteritis virus (EAV) from equine semen used for artificial insemination is urgently needed. Recent medical studies suggest that a double semen processing technique of density gradient centrifugation followed by a 'swim-up' can provide virus-free sperm preparations for assisted reproduction. Objective: To investigate the use of the double semen processing technique to obtain virus-free sperm preparations from stallion semen containing EAV. Methods: Aliquots of an ejaculate from an uninfected stallion were spiked with virus and processed by the double processing tech...
Reardon R, Kummer M, Lischer C.To report a novel technique for cervical vertebral fusion in a foal with cervical vertebral malformation (CVM). Methods: Case report. Methods: A 3-month-old Warmblood filly with ataxia, weakness, and stenotic myelopathy at the level of the articulation of the 6th (C6) and 7th (C7) cervical vertebrae had a 7-hole broad locking compression plate (LCP) applied to the ventral aspect of C6 and C7 using seven 5.0-mm locking screws. Revision surgery was required to replace the self-drilling screws, which had migrated, with longer non self-drilling screws. Fusion and growth of the vertebrae were monit...
Raza F, Babasyan S, Larson EM, Freer HS, Schnabel CL, Wagner B.Interleukin-4 (IL-4) is a key cytokine secreted by type 2 T helper (Th2) cells that orchestrates immune responses during allergic reactions. Human and mouse studies additionally suggest that basophils have a unique role in the regulation of allergic diseases by providing initial IL-4 to drive T cell development towards the Th2 phenotype. Equine Culicoides hypersensitivity (CH) is a seasonal immunoglobulin E (IgE)-mediated allergic dermatitis in horses in response to salivary allergens from Culicoides (Cul) midges. Here, we analyzed IL-4 production in peripheral blood mononuclear cells (PBMC) o...
Kallerud AS, Hernlund E, Byström A, Persson-Sjodin E, Rhodin M, Hendrickson EHS, Fjordbakk CT.Little is known regarding how trotting through curves affects locomotion symmetry in Standardbred trotters. Objective: To investigate differences in objectively measured Standardbred trotter vertical motion symmetry between straight and non-banked, curved sections of oval trotting tracks during exercise warm-up, using a wireless inertial measurement unit (IMU) system. Methods: Cross-sectional, observational study. Methods: Sixteen horses were included. Mixed models were used to assess associations between symmetry, track segment (straight vs curve) and stride duration. Results: Significant res...
Berger JM, Bell SA, Holmberg BJ, Madigan JE.A 15-year-old Saddlebred gelding used for competitive pleasure driving had a 1-year history of head shaking while pulling a cart. Results: The horse had cystic corpora nigra in both eyes and concomitant classic and operant conditioned responses to wearing a bridle with bilateral eye covers (blinkers). Results: Deflation and coagulation of the cysts with an infrared diode laser and behavior modification consisting of desensitization and counter-conditioning were used to successfully restore performance. Conclusions: Behavioral changes in horses can result from a combination of physical and psyc...
Spadavecchia C, Levionnois O, Kronen PW, Leandri M, Spadavecchia L, Schatzmann U.To investigate effects of isoflurane at approximately the minimum alveolar concentration (MAC) on the nociceptive withdrawal reflex (NWR) of the forelimb of ponies as a method for quantifying anesthetic potency. Methods: 7 healthy adult Shetland ponies. Methods: Individual MAC (iMAC) for isoflurane was determined for each pony. Then, effects of isoflurane administered at 0.85, 0.95, and 1.05 iMAC on the NWR were assessed. At each concentration, the NWR threshold was defined electromyographically for the common digital extensor and deltoid muscles by stimulating the digital nerve; additional el...
Bishop RC, Kemper AM, Wilkins PA, McCoy AM.Equine gastric ulcer syndrome (EGUS) is a common and significant cause of morbidity in horses, with a range of clinical signs, including inappetence, colic and poor performance. Hospitalised horses are exposed to factors that may induce EGUS, including fasting and nonsteroidal anti-inflammatory drug (NSAID) administration, and may be at risk for development of squamous (ESGD) and glandular gastric disease (EGGD). Prophylactic anti-ulcer medication is often prescribed for these patients, but drug selection is complicated by different aetiology and response to treatment of ESGD and EGGD. Objecti...
Logan AA, Nielsen BD, Hallock DB, Robison CI, Popovich JM.A current trend in equine research is technology development to minimize the subjective nature of gait analysis. One such technology is the Tekscan Hoof System, which records force and area loaded by the hooves during motion. The objective of this study was to determine the test-retest reliability of the Tekscan Hoof System between two sessions, and the recordings within those sessions. Four mature Standardbred geldings wore Tekscan Hoof System sensors on both front hooves, secured by glue-on shoes (SoundHorse Technologies). Horses were exercised in AM and PM sessions. In each session, horses ...
Francisco I, Arias M, Cortiñas FJ, Francisco R, Mochales E, Sánchez JA, Uriarte J, Suárez JL, Morrondo P, Sánchez-Andrade R, Díez-Baños P....Two groups of autochthonous Pura Raza Galega (PRG) horses, one comprising 483 animals under a silvopasturing regime, and the other comprising 72 PRG horses managed in farms, were used to analyse the effect of silvopasture on infection by endoparasites. Results were considered according to the age and the sex of the horses. Faecal samples were individually collected from each animal and analysed by the coprological flotation, sedimentation and migration techniques. Coprocultures were also done to identify the main strongylid genera affecting the horses. Eggs from the gastrointestinal nematoda P...
Pechanec MY, Beall JM, Katzman S, Maga EA, Mienaltowski MJ.Tendinopathies remain the leading contributor to career-ending injuries in horses because of the complexity of tendon repair. As such, cell-based therapies like injections of adipose-derived mesenchymal stem cells (ADMSCs, or MSCs) into injured tendons are becoming increasingly popular though their long-term efficacy on a molecular and wholistic level remains contentious. Thus, we co-cultured equine MSCs with intrinsic (tendon proper) and extrinsic (peritenon) tendon cell populations to examine interactions between these cells. Gene expression for common tenogenic, perivascular, and differenti...
Samuel CA, Allen WR, Steven DH.Microcotyledons, which are a distinctive feature of the mature equine placenta, are fully formed by Day 150 of gestation. The fetal component of each microcotyledon is developed from several primary folds of trophoblast which become elaborately subdivided as gestation proceeds. These changes are reflected in the structure of the maternal crypts, which receive the fetal villi. Between Days 60 and 150 of gestation the maternal epithelium is greatly reduced in height. No such change occurs on the fetal side of the placenta, but between Days 100 and 250 a progressive indentation of the epithelium ...
