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.
Lees MJ, Fretz PB, Bowen CV, Leach DH.Equine limb wounds often heal slowly by epithelialization, and large scars are a frequent end result. In some ways, they resemble the wound associated with human tibial injuries. The literature indicates that previous investigators have failed to transfer free skin flaps successfully in the horse. In this paper, we review our experimental work with the deep circumflex iliac flap in the horse. Dissections of 20 cadavers confirmed the anatomical consistency of the flap. Four flaps survived well when elevated as island flaps, but five orthotopic and nine heterotopic free flap transfers all failed...
Angelos JA, Marti E, Lazary S, Carmichael LE.The DNA from equine sarcoid samples from New York State and Switzerland was isolated and probed with bovine papillomavirus type 1 (BPV-1) to determine if BPV genomes were present. Twelve of 13 sarcoids from New York State and 17/20 sarcoids from Switzerland contained DNA that hybridized to the BPV-1 probe. Restriction enzyme analysis of the positive samples demonstrated restriction fragment profiles characteristic of BPV-1 in 22 sarcoids and restriction fragment profiles characteristic of bovine papillomavirus type 2 (BPV-2) in 7 sarcoids. In addition, three tissues histologically diagnosed as...
Brooks M, Leith GS, Allen AK, Woods PR, Benson RE, Dodds WJ.Bleeding diathesis in a Quarter Horse filly was caused by von Willebrand disease. Hemorrhage occurred mainly from mucosal surfaces and after trauma. Quantitative and qualitative measurements of plasma von Willebrand factor (vWF) documented a specific deficiency of vWF high molecular weight multimers, and concurrently greater than expected deficiency of vWF activity relative to vWF concentration. These findings are characteristic of type-II von Willebrand disease in human beings. Application of vWF assays used in human and small animal medicine now permits evaluation of vWF and diagnosis of von...
Clark ES, Gantley B, Moore JN.The effects of intravenous (iv) infusion of endotoxin for 60 mins at a cumulative dosage of 0.03 micrograms/kg bodyweight on systemic arterial, right atrial and pulmonary arterial pressures, heart rate, cardiac output, and derived pulmonary vascular resistance and total peripheral vascular resistance were compared to the effects of iv infusion of saline solution in four healthy horses. Heart rate was increased significantly after endotoxin infusion, although diastolic arterial pressure, systolic arterial pressure, electronically averaged arterial pressure, cardiac output, total peripheral resi...
Broadstone RV, LeBlanc PH, Derksen FJ, Robinson NE.The in vitro contractile and relaxant responses of tracheal smooth muscle strips (TSM) and third-generation bronchi (3B) of control horses and horses with recurrent obstructive disease (heaves) were compared. Acetylcholine (ACH) sensitivity of the diseased tissues was less than that of tissues from control horses, especially at the level of the third generation (EC50 controls 15 +/- 11 microM vs 81 +/- 17 microM for heaveys). Despite tracheal and bronchial hyporesponsiveness to ACH, these tissues from heavey horses were hyperresponsive to EFS. The inhibitory effect of isoproterenol and electri...
Riley CB, Yovich JV.Fractures of the patella in the horse are infrequently reported
in the literature. Most of these have been associated with trauma
or sudden forceful contraction of the quadriceps resulting in an
avulsion fracture of the patella (Parks and Wyn-Jones 1988).
There have been few reports of fractures associated with des-
motomy of the medial patellar ligament to correct upward
fixation of the patella (Wright and Rose 1989; Gibson ef ul1989).
This paper describes one such case including the radiographic
findings before the desmotomy, after fracture of the patella and
after arthroscopic trea...
Weitkamp LR, Kenney RM, Bailey E, MacCluer JW, Brown JS, Blanchard TL, Sertich PL, Love CC, Hunt PR.Histological features of the endometrium, as assessed in biopsy samples, were related to Standardbred mare genotypes for transferrin, esterase (as a control) and equine leucocyte antigens (ELA). Pathological changes were found more frequently in each successively older age group of mares. Among mares aged 6-19 years, there were significant pathologic changes on first examination following an infertile breeding season for 46 of 90 (51%) of transferrin homozygotes and 50 of 146 (34%) of transferrin heterozygotes. The difference between the two groups was significant for the total data (chi 1(2) ...
Trotter GW, McIlwraith CW, Yovich JV, Norrdin RW, Wrigley RH, Lamar CH.The effects of the corticosteroid 6-alpha-methylprednisolone acetate on normal equine articular cartilage were evaluated, using the middle carpal joint in 4 clinically normal young horses. One middle carpal joint of each horse was injected 3 times with 100 mg of 6-alpha-methylprednisolone acetate, at 14-day intervals. The opposite middle carpal joint (control) was injected with 2.5 ml of lactated Ringer solution at the same intervals. Effects were studied until 8 weeks after the first injection. Evaluation included clinical and radiographic examination, and gross, microscopic, and biochemical ...
Zhang JJ, Muzs LZ, Boyle MS.Three experiments were conducted to assess the structural and functional changes of stallion spermatozoa in response to the calcium ionophore A23187, and to determine individual variation between stallions. In Experiment 1, changes in the acrosome of spermatozoa exposed to 7.14 microM A23187 for fixed times between 0 and 120 min were examined. There was a steady increase with time in the number of spermatozoa undergoing the acrosome reaction although the rate of increase differed between stallions. Sperm motility decreased sharply when incubation was extended beyond 30 min. In Experiment 2, th...
Blanc G, Magistrini M, Palmer E.Semen from three ejaculates from each of 4 stallions was frozen in liquid nitrogen. Morphology was evaluated by coating the spermatozoa with fluorescein-labelled Concanavalin A (FITC-ConA2) and motility was measured by computer-assisted image analysis. Coating was performed at each step of the freezing procedure (dilution, cooling, addition of glycerol and freeze-thawing) and observations were made after each step, to evaluate changes, or after subsequent steps, to determine protection provided by the coating method. All the parameters showed progressive changes during the freezing procedure. ...
May SA, Hooke RE, Lees P.The concentration of Percoll required for isolating equine peripheral blood mononuclear cells has been reinvestigated. A poor cell yield was obtained at the 60 per cent concentration already reported. It is recommended that workers specifically interested in high yields of mononuclear cells, for investigation of lymphocyte and monocyte functions, use a concentration of 65 per cent Percoll. However, workers wishing to isolate pure populations of equine neutrophils might consider a concentration of 70 per cent in the upper layer of Percoll used to retain the mononuclear cells.
Trout DR, Hornof WJ, O'Brien TR.Radiography and soft tissue- and bone-phase scintigraphy were performed on 14 clinically normal horses and 35 horses in which definite, probable, or possible navicular disease had been diagnosed. The specificity of radiography and scintigraphy in revealing signs of navicular disease were nearly equal; however, the sensitivity of scintigraphy appeared to be greater than that of radiography. The greatest sensitivity and specificity were achieved when the results of radiography and scintigraphy were evaluated together. Differences in sensitivity were greatest when scintigraphy revealed lesions no...
Bjørn H, Sommer C, Schougård H, Henriksen SA, Nansen P.This study was undertaken to establish whether anthelmintic resistance was present in nematode parasites of horses in Denmark. Sixteen horse farms were selected for faecal egg count reduction (FECR) tests to measure the efficacy of the anthelmintic used. Resistance to benzimidazole anthelmintics was found on 13 of the 16 farms, with FECR values ranging from 80.0% to -101.3%. On the remaining 3 farms FECR was 100.0%, 99.3% and 97.2%. Results of a questionnaire study on anthelmintic usage, parasite control measures and management practices showed that horses in this study were treated on average...
Uhlinger C.A herd of 15 mature riding horses with a history of anorexia, weight loss, and lethargy was examined. The animals had been fed a 50/50 mixture of commercial sweet feed and corn screenings contaminated with a heavy growth of Fusarium moniliforme. Thirteen of the horses had one or more neurologic signs. The most characteristic signs were profound depression and mild ataxia. Over the 19-day course of the epizootic, the horses had increasing severe neurologic deficits, including unilateral blindness and delirium. Despite the clinical appearance of dehydration, 12 horses had low PCV (16 to 27%), he...
Kirkpatrick JF, Liu IM, Turner JW, Bernoco M.Twenty-six free-roaming feral mares were immunized against porcine zonae pellucidae (PZP) between February and May, 1988. Eight sexually mature mares received 2 inoculations 2 weeks apart, and 18 mares received 3 inoculations at intervals of 2 and 4 weeks. Analysis of urinary oestrone conjugates (E1C) and non-specific progesterone metabolites (iPdG) in samples collected in October, 1988, revealed that none of the 18 mares that received 3 and only 1 of the 6 mares that received two inoculations were pregnant, whereas 3 of 6 sham-injected control mares and 5 of 11 untreated mares were pregnant. ...
Rossdale PD, Ousey JC, Cottrill CM, Chavatte P, Allen WR, McGladdery AJ.Between 1985 and 1990, 25 Thoroughbred mares were classified as having an abnormal pregnancy on the basis of precocious signs of impending parturition. Throughout the remainder of their pregnancies, plasma progestagen and mammary secretion calcium concentrations were monitored. After parturition, evidence of placental pathology was recorded and their foals were assessed with regard to adrenocortical function and behaviour. Seven pony mares were used to establish a model of placental pathology and, following induced placental separation, were subjected to the same protocol. Control animals cons...
Houghton E, Holtan D, Grainger L, Voller BE, Rossdale PD, Ousey JC.Radioimmunoassay (RIA) and gas chromatography-mass spectrometry (GC-MS) were used to determine plasma progestagen concentrations in the normal and premature foal. Radioimmunoassay provides a profile of plasma progestagens with respect to time but, due to the non-specific nature of the technique and without prior chromatographic purification, quantitative data based on RIA analysis must be interpreted with caution. In contrast, the greater specificity of GC-MS allows identification of specific plasma progestagens and measuring of multiple analytes in a single analysis. Both techniques demonstra...
Cottrill CM, Jeffers-Lo J, Ousey JC, McGladdery AJ, Ricketts SW, Silver M, Rossdale PD.One hundred twenty-four horse placentas were evaluated according to gross appearance, weight and surface area. Grossly abnormal placentas were photographed, and histological sections were taken from abnormal appearing areas, and from representative areas (pregnant horn, non-pregnant horn, body and cervical pole) in both normal and abnormal placentas. Information about the resulting foals was obtained and correlations examined. Histological sections were reviewed and related to the resulting foals. Four normal fresh placentas were infused with dyes to ascertain the blood supply to various areas...
Martin BB, Nunamaker DM, Evans LH, Orsini JA, Palmer SE.Circumferential wiring was used to repair 12 mid-body fractures and four large basilar fractures of proximal sesamoid bones in 15 horses. Eighteen-gauge stainless steel wire was placed around both fragments in five horses, and through the proximal fragment and around the distal fragment in 10 horses. The horses were returned to work when they were clinically sound and fracture healing was evident radiographically. Eleven horses resumed athletic performance, three horses were used as breeding animals, and one horse was retired. Five horses performed at an athletic level equal to or better than ...
Busch NA, Ranu HS, Silver IA.Evidence indicating that comparison of a particular animal trace with a population average is an insufficient test of the health of a limb is presented. The methodology involves representing each of three recorded force components (vertical, lateral, and transverse) as a Fourier-Legendre series; the coefficients in the series represent the trace. A history for the horse is built by accumulating the coefficients (along with pertinent experimental data such as date, sex, weight, height, and in the case of race horses the date of last race) over a long duration. Then, on each subsequent recording...
Howarth S, Lucke VM, Pearson H.A retrospective analysis was performed on 48 cases of suspected neoplasia involving the equine external genitalia. Forty nine squamous cell carcinomata (SCC) and 23 squamous papillomata (SP) were identified. Two cases of epithelial hyperplasia and one case of habronemiasis were also recognised histopathologically. The glans penis was the most common site of tumour development accounting for 53 per cent of cases of SCC and 61 per cent of SP. The urethral diverticulum, urethral process or urethra was involved in 27.6 per cent (8/29) of cases of SCC. Twelve per cent (5/41) of cases of SCC were co...
Dyson S.Clinical, ultrasonographic and radiographic features of proximal suspensory desmitis in the forelimb and the hindlimb are described. Acute cases may present with slight, localised, oedematous swelling, heat, distension of the medial palmar (plantar) vein and/or pain, whereas chronic cases or those rested immediately after onset of lameness usually have no detectable clinical signs suggestive of the source of pain. In these cases local analgesia is required to identify pain in the proximal metacarpal (metatarsal) region. Transverse ultrasonographic images of the suspensory ligament usually yiel...
Freestone JF, Wolfsheimer KJ, Ford RB, Church G, Bessin R.Ponies were evaluated for their response to feed withholding and exogenous administration of corticosteroids (dexamethasone 0.04 mg/kg intramuscular [IM]) in an attempt to reproduce the hyperlipemia syndrome. Because insulin resistance has been associated with hyperlipemia, all ponies were initially evaluated for insulin response to an oral glucose load and normal dexamethasone suppression of serum cortisol. Four ponies were identified as hyperinsulinemic reflecting insulin resistance. All ponies had suppressed cortisol concentrations following dexamethasone administration. Feed withdrawal res...
Shoemaker RS, Martin GS, Hillmann DJ, Haynes PF, McClure JR, Schneiter HL.Two horses became acutely lame following a fall during strenuous exercise and were diagnosed as having disruption of the caudal component of the reciprocal apparatus. Clinical signs consisted of lameness of the right pelvic limb, characterized by flexion of the hock and simultaneous extension of the stifle. Radiography revealed an avulsion fracture from the supracondylar tuberosity and fossa of the distal portion of the femur in one horse. Clinical and radiographic findings indicated avulsion of the lateral origin of the gastrocnemius and superficial digital flexor muscles. Treatment consisted...
Freitas TV, Fortes-Dias CL, Diniz CR, Velarde DT, Freitas CF.1. A comparative study was carried out on horses immunized with Crotalus durissus terrificus venom using four different inoculation procedures, which included the use of Freund's adjuvant, A1(OH)3 and liposomes as adjuvants. The antibody titer was assessed by enzyme linked immunosorbent assay (ELISA) and the neutralizing potency by the neutralizing median effective dose (ED50). 2. The inoculation schedule used in horses to obtain antivenom serum consisted of sc injections of a 7.5 mg venom starting dose in 5.0 ml sterile saline emulsified with an equal volume of Freund's complete adjuvant. One...
Enders AC, Liu IK.The equine blastocyst becomes fixed in position in the uterus on approximately Day 16 of gestation, but allantochorionic villi are not formed until about Day 50. The purpose of this study was to examine evidence that the blastocyst is orientated during this time period, and to determine what morphological features might assist retention of the position of the blastocyst within the uterus. Implantation sites were collected on Days 10-42 of gestation, and the reproductive tracts perfused with fixative for light and electron microscopic examination. The conceptus is found at the bend of a uterine...
Nielsen AH, Gotfredsen P, Nielsen PB, Hyttel P, Poulsen K.1. Species specific problems complicating the measurement of prorenin and renin concentrations were studied in bovine, hog and horse plasma. 2. In contrast to horse renin, bovine and hog renin reacted with rat angiotensinogen, allowing measurement of the plasma renin concentration in cattle and hog with rat angiotensinogen as exogenous substrate. 3. Trypsin treatment of plasma in order to activate prorenin generated an interfering angiotensin I immunoreactive material in all three species, most extensively in horse plasma. 4. This material could be removed in bovine and hog plasma by a cation-...
Medina-Bautista F, Nocera I, Sánchez de Medina A, Di Franco C, Briganti A, Morgaz J, Granados MDM.The objective of this study was to evaluate the feasibility and efficacy of the ultrasound-guided thoracolumbar erector spinae plane (TL-ESP) block in standing horses. A total of 24 injections ( = 12) were performed at the L1 level using either 0.1 mL/kg of saline solution (SS group) or 2% lidocaine (LID group). The block feasibility was assessed based on needle visualization and injection time, while efficacy was evaluated through craniocaudal and dorsoventral (DV) spread using the pinprick technique over 270 min. Desensitization was observed at least once in 100% of horses in the LID group a...
Taylor DEF, Lancaster BE, Ellis AD.Visual observation to record grass intake is time-consuming and labour-intensive. Technological methods, such as activity monitors, have been used but only record head position. This study aimed to evaluate sound recorders attached to headcollars to acoustically measure grass intake behaviour in horses as a low-cost alternative method. Pilot Study 1 assessed 6 × 11 min periods comparing bites/min and chews/min between video footage (VD) and sound recorders (SR). Grazing was identified audibly (SR) and visually through soundwave pattern software (SR). Chew rates (SR: 47 ± 5 chews/min, VD: 43 ...
Da Silva E, Martín-Cano FE, Gómez-Arrones V, Gaitskell-Phillips G, Alonso JM, Rey J, Becerro L, Gil MC, Peña FJ, Ortega-Ferrusola C.Equine endometritis is one of the main causes of subfertility in the mare. Unraveling the molecular mechanisms involved in this condition and pinpointing proteins with biomarker potential could be crucial in both diagnosing and treating this condition. This study aimed to identify the endometritis-induced changes in the endometrial proteome in mares and to elucidate potential biological processes in which these proteins may be involved. Secondly, biomarkers related to bacterial endometritis (BE) in mares were identified. Uterine lavage fluid samples were collected from 28 mares (14 healthy: ne...
Lawson EF, Ghosh A, Grupen C, Netherton J, Aitken RJ, Smith ND, Lim R, Drury HR, Pickford R, Gibb Z, Baker M, Tanwar PS, Swegen A.In many mammals, the lipid platelet-activating factor (PAF) has important functions in female reproduction and fertility. This study shows that PAF is present in the reproductive tissues of mares and is involved in processes related to ovulation and early pregnancy. Platelet-activating factor (PAF) has been implicated in a number of reproductive processes ranging from ovulation to embryo motility but has not been widely explored in the mare. To identify the presence and examine the role of PAF in the equine periconception processes, targeted mass spectrometry coupled with chromatographic separ...
Byron M, Lection J, Foster RA, Chenier T, Wagner B, Diel de Amorim M.Prostaglandins have many roles in the equine reproductive tract, including but not limited to luteolysis, luteal support, ovulation, transport through the uterine tube, uterine contraction, embryonic mobility, inflammation, and fibrosis. Altered secretion of inflammatory proteins are likely to disrupt the balance of endometrial function and could impair fertility. Our overall goal was to measure the expression of several prostaglandin- and inflammation-related genes in mares with different degrees of endometrial histological changes. Our hypothesis was that mares with neutrophilic and lymphocy...
Leduc L, Abraham M, Slack J.Atrial fibrillation (AF) is a rarely reported arrhythmia in otherwise healthy newborn foals, with a single case of cardioversion using procainamide administration described in the literature. Two neonatal Thoroughbred colts were presented to an equine hospital because of an irregularly irregular tachyarrhythmia and poor latching when trying to nurse. History, physical examination, and initial diagnostic testing including ECG and echocardiography confirmed AF without structural heart disease. The 1st foal converted into normal sinus rhythm after treatment with IV metoprolol and quinidine. The 2...
Fiske-Jackson A.Equine neoplasia poses challenges in surgical management owing to their diverse locations and potential for aggressive behavior. Surgical interventions aim for complete excision while minimizing cosmetic and functional impairments. Techniques such as laser ablation and electrochemotherapy offer minimally invasive options for accessible tumors. For deeper or larger masses, surgical excision with adequate margins remains the gold standard. Preoperative biopsy and imaging guides surgical planning, ensuring complete tumor removal while preserving vital structures. Close adherence to a strict surgi...
Eertink LG, Swope M, Uprety T, Sreenivasan C, Page AE, Adam EN, Wang D, Li F.Equine rotavirus A (ERVA) can cause foal diarrhoea and the most common ERVA genotypes are G3P[12] and G14P[12]. Since the introduction of a monovalent killed G3P[12] vaccine, infection in neonates has decreased. We aimed to determine the dynamics and longevity of maternally derived anti-G3P[12] neutralizing antibodies (NAbs) in foals and what, if any, cross-reactivity exists between maternally derived NAbs against G14P[12]. Serum samples were collected from 50 mare-foal pairs before each vaccination and up to 6 months post-foaling for mares and up to 7 months of age for foals. These samples we...
Knych HK.Pharmacokinetics is the study of the movement of drug in the body and includes the processes of absorption, distribution, metabolism, and excretion. Pharmacodynamics is the pharmacologic effect of the drug on the body. The pharmacokinetics of a drug determines its pharmacologic effect. Pharmacokinetic studies describe drug concentrations while pharmacodynamics allow for assessment of drug effects. Combined pharmacokinetic/pharmacodynamic studies allow for integration of drug concentrations with pharmacologic effect. Data generated from pharmacokinetic studies can be especially useful in establ...
Pusterla N, Lawton K, Barnum S, Vitomirov A, Anaya S, Naranatt P, Swadia H, Mendonsa E.The objective of this study was to evaluate a point-of-care (POC) PCR assay for the detection of Salmonella spp. in pooled environmental samples collected at an equine veterinary hospital. A total of 945 environmental samples were collected from high-risk areas, including ICU and isolation stalls, high-traffic areas, treatment rooms, and surgical suites. The environmental samples were collected using drag swabs placed in selenite broth and individually incubated at 35 °C for 20 h. Following the incubation period, 1 mL of up to 10 individual environmental samples were pooled together. Each poo...
Nabenishi H, Tsuda T, Omoya Y, Ishii T.This study aimed to detect characteristic changes in the behavior and body surface temperature (BST) of pregnant mares before parturition using camera image analysis. A total of 53 pregnant Thoroughbred mares, which were individually stabled in box stalls, were included in this study. The mares were continuously monitored using a digital camera system comprising a thermal imaging camera and a visible camera. For the automatic determination of the x and y coordinates of each mare, the centroid of the mares was calculated using image processing software. Subsequently, trajectory analysis was per...
Maurer T, de Preux M, Precht C, Vidondo B, Koch C.To assess the accuracy of computer-assisted surgery (CAS) of equine cervical vertebrae using a purpose-built cervical frame (CF) for neck stabilization. Methods: Experimental cadaveric study. Methods: Six whole fresh equine cadavers. Methods: Cadavers were positioned in dorsal recumbency with the neck extended within the CF. A cone-beam computed tomography (CBCT)-based surgical navigation system with optical tracking was used. A ventral approach exposed cervical vertebrae C3-C5. In each cadaver, 12 drill corridors were prepared with the patient tracker on the CF (position CF), followed by 12 c...
Marchio SP, El-Sheikh Ali H, Scott MA, Barbosa Fernandes C, Scoggin KE, Troedsson M, Boakari Y.Despite its critical role in protecting the fetus, the amniotic membrane remains poorly understood in the context of disease response. The equine amniotic membrane is an important physical barrier to the amniotic compartment, and there is evidence that it may contribute to surfactant synthesis. Surfactants are essential for normal fetal lung development, and disruptions in its availability may be linked to future neonatal complications. Therefore, understanding the molecular changes that occur in fetal-maternal tissues during placentitis would clarify how this condition leads to abortion, pret...
Pfau T, Forbes B, Sepulveda-Caviedes F, Chan Z, Weller R.Based on fundamental mechanics, movement and force associate head and pelvic movement asymmetry with asymmetry of force production. We investigate, how often racehorses undergoing strenuous training regimens show evidence of switching between "preferred" limbs, i.e. one limb producing increased force, when assessed at monthly intervals? We hypothesize that clinical asymmetry thresholds designed for "detecting lameness" are frequently exceeded and that when applying previously established Thoroughbred-specific repeatability values, horses rarely switch between showing left- and right-sided asym...
Carmona JU, López C, Jurado-Grisales C.Platelet-rich plasma (PRP) is widely utilized as a routine treatment for chronic musculoskeletal conditions in horses, such as osteoarthritis, tendinopathies, and desmopathies. This effectiveness stems from the high concentration of growth factors and anti-inflammatory cytokines that are released upon activation of this orthobiologic agent, whether activated endogenously or exogenously. Despite its growing popularity, there is a notable absence of instructional videos that demonstrate the techniques for obtaining PRP in horses. This study examines a double centrifugation tube method for obtain...
Turcotte G, O'Sullivan TL, Rossi TM, Spence KL, Winder CB, Greer AL.Horses are frequently transported, creating opportunities for the spread of pathogens. Disease transmission models for equine infectious diseases face limitations on their generalizability due to challenges in describing equine movement and the structure of their contact networks beyond simplistic assumptions. This study aimed to combine a stochastic, agent-based, SEIR model for equine influenza disease dynamics with an observed Ontario, Canada equine contact network structure to quantify the potential magnitude of equine influenza outbreaks in Ontario competition horses under different condit...
Arantes JA, Rabelo IP, Bermudes L, Lacerenza MD, Mendes RP, Corrêa RR, Yamada DI, Valadão CAA, Dória RGS.This study aimed to compare the sedation quality and cardiorespiratory and behavioral effects of detomidine administered intravenously, either in intermittent boluses or as a continuous rate infusion, with butorphanol in horses pre-medicated with acepromazine for odontoplasty procedures. Unassigned: A prospective clinical study was conducted with fifteen adult horses randomly assigned to two groups: Bolus group (BG, = 7) and Infusion group (IG, = 8). Both groups received acepromazine premedication, followed by detomidine administration (bolus or infusion). Butorphanol was administered either...
Aragona F, Rizzo M, Arfuso F, Arrigo F, Fazio F, Giudice E, Faggio C, Piccione G, Giannetto C.Homeostasis and inflammation are two opposing physiological processes that are driven by the circadian clock. Objective: The study aim was to investigate the biological rhythm of the C-reactive protein (CRP) and Interleukin-6 (IL-6) in horses. Methods: Eight clinically healthy Italian saddle gelding horses, housed in individual boxes and subjected to a natural 12/12 L/D cycle, were enrolled. Blood samples were performed every 4 hours over a 48-hour period. Results: A positive correlation was found between CRP and IL-6 on both days of monitoring. Both parameters showed a daily rhythm; CRP acrop...
Duggan MJS, Kearney C, Baltrimaite M, Labberté MC, Gibney R, Brama PAJ.The aim of this study was to refine the lipopolysaccharide (LPS)-induced synovitis model in normal carpal joints of Thoroughbred horses by comparing two low LPS doses. A further aim was to investigate the relationship between the induced synovitis and lameness. The study design consisted of two phases using nine horses with a unilateral crossover design and a within-animal saline control. Synoviocentesis was performed at post-injection hour (PIH) 0, 8, 24, 72 and 168, allowing for synovial fluid cytology and biomarker analysis. Objective gait and thermographic analysis were used to objectively...
In light of the increasing reports of anthelmintic (AH) resistance in equids, a national survey on helminth control practices was distributed to 42 528 keepers. A total of 4 344 responses was obtained. Respondents implemented preventive pasture practices with varying frequency according to the age of the animals, such as pasture rotations (78.1-80.6 %), excrement removal from pastures several times a year (15.9-27.2 %) and/or mixed or rotational grazing with ruminants (14.5-18.1 %). A majority of keepers routinely used AH treatments even though they did not perceive any major risk to the...
subsp. (SEZ) is a bacterium that primarily affects horses but can also infect other animals and humans. In 2021-2022, two SEZ outbreaks occurred in Abruzzo, Italy: one in humans linked to unpasteurized cheese (37 cases) and another in donkeys (4 deaths). These events led researchers to investigate SEZ in horses, donkeys, and a mule in the regions of Abruzzo and Molise, focusing on antibiotic resistance and genetic traits. A total of 490 nasal and genital swabs were collected from equids and analyzed for SEZ presence, with 61 positive samples. Isolated strains underwent antimicrobial suscepti...
Gillen A, Hassel D, Gonzalez S, Savage V, Bauck A, Freeman D, Archer DC.Obstruction by strangulating lipoma (SLO) is one of the most common causes of small intestinal strangulation in horses and is fatal without surgery. Current knowledge of risk factors for SLO is limited to horse signalment features. To date, other risk factors have not been investigated. Objective: To investigate horse- and management-level risk factors for SLO using a population of healthy horses as controls. Methods: Matched, case-control study. Methods: A prospective, international multicentre study was conducted in the UK and USA between January 2022 and May 2024. Cases were horses with SLO...
Klass LG, Diekmann I, Andreotti S, Mbedi S, Sparmann S, Schenk T, Anderson HP, Bellaw J, Nielsen MK, Krücken J, von Samson-Himmelstjerna G.Strongyles, especially non-migratory Strongylidae, are the most common equine gut parasites, and typically occur in mixed infections with 10 - 20 species per host. Current knowledge on strongyle species prevalence and within-host tropism is sparse. Herein species composition of mixed strongyle infections of 12 naturally infected untreated young horses, based on strongyle eggs extracted from faeces, cultured third stage larva and luminal worms collected from ventral and dorsal colon was examined. Species were identified using a cytochrome c oxidase I (COI) metabarcoding approach allowing differ...
Takahashi Y, Pfau T, Tsuruoka F, Yoshida T, Edwards WB, Mukai K.To identify the race- and horse-level factors affecting stride parameters during Thoroughbred races in Japan. Unassigned: Global Navigation Satellite System sensors were attached to 921 horses (1,189 starts) participating in 83 races, with distances ranging from 1,000 to 1,800 m, held from April through July 2024. Stride frequency and stride length were calculated from speed spectrograms at 3 racing phases (phase 1, 200 m after gate open; phase 2, 10 m after reaching the final straight stretch; and phase 3, 130 m before the finishing line). Additionally, 10 variables (race distance, surface ty...
Boado A, Pollard D, Lopez-Sanroman FJ, Dyson S.There is limited information regarding orthopaedic injuries in dressage horses. This study assessed the prevalence of injuries in a mixed referral and first opinion population of 272 horses training and competing in dressage, 238 of which were followed up one to five years after injury. Warmblood (55.8%) and Iberian (38.6%) breeds predominated. The median age was 8 years (interquartile range [IQR] 5,11; range 1,21). Horses were examined due to lameness (85.3%) or poor performance (14.7%). The median lameness grade was 2/5 (IQR 2,4; range 0,4). Forelimb lameness was more prevalent than hindlimb...
Ren W, Zhou J, Zhu J, Zhang J, Zhao X, Yao X.The ovary is among the earliest organs to undergo age-related degeneration, limiting the reproductive potential of elite horses and constraining the growth of the equine industry. Follicular development during estrus is a key determinant of fertility, yet the molecular mechanisms underlying its decline, particularly at the level of specific ovarian cell types, remain poorly understood in equids. Here, we constructed a single-cell transcriptomic atlas to investigate ovarian changes in Kazakh horses. Using single-cell RNA sequencing (scRNA-seq), we profiled 112,861 cells from follicle-containing...
Gröndahl G, Righetti F, Aspán A, Bjerketorp J, Frosth S, Frykberg L, Jacobsson K, Guss B, Paillot R, Flock JI, Henriques-Normark B, Waller AS.Strangles, caused by Streptococcus equi subspecies equi (S. equi), is a prevalent infectious disease of horses. This is the first report on the use of a new vaccine, Strangvac, in a natural outbreak of strangles. Objective: To measure the effects of Strangvac vaccination during an outbreak of strangles at a Swedish farm. Methods: Longitudinal cohort study. Methods: Healthy horses (n = 17) were vaccinated on day 0, which occurred 23 days after strangles was first confirmed in three unvaccinated horses on the same farm. Blood serum samples were collected on day 0, day 28 and day 489. A com...
Castanheira CIGD, Taylor S, Skiöldebrand E, Rubio-Martinez LM, Hackl M, Clegg PD, Peffers MJ.The aim of this study was to identify differentially expressed microRNAs (miRNAs) in serum and synovial fluid (SF) samples of control horses and those with osteoarthritis (OA) to identify potential candidates for biomarkers of disease. Total RNA was extracted from serum and SF samples of control (n = 4) and OA (n = 9) horses and sequenced. Differential expression analysis, pathway analysis and miRNA target prediction were performed. A group of six miRNAs (eca-miR-199a-3p, eca-miR-148a, eca-miR-99b, eca-miR-146a, eca-miR-423-5p and eca-miR-23b) was selected for validation in an independent coho...
Lee S, Hector RC, Hess AM, Wotman KL.To determine whether dexmedetomidine prolongs corneal anesthesia following subconjunctival ropivacaine injection in healthy equine eyes. Methods: Ten horses with normal ophthalmic exams were enrolled in a randomized, blinded, crossover experiment with a minimum 4-week washout between treatments. Baseline corneal touch thresholds (CTT, cm) were measured via esthesiometry and a subconjunctival injection was performed in the treatment eye with ropivacaine (R, 0.3 mL 0.5%) or dexmedetomidine-ropivacaine (DR, 0.1 mL 0.5 mg/mL + 0.2 mL 0.5%) and saline (control, 0.3 mL) in the contrala...
