Modeling in equine research involves the use of mathematical, statistical, or computational techniques to simulate and analyze various aspects of horse biology, behavior, and health. These models can help researchers understand complex systems, predict outcomes, and optimize management practices. Applications of modeling in equine studies include gait analysis, disease spread prediction, and nutritional requirement assessment. By integrating data from diverse sources, models can offer insights into physiological processes and inform decision-making in veterinary care and equine management. This page assembles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and advancements in modeling within the context of equine science.
Leathwick DM, Sauermann CW, Geurden T, Nielsen MK.A previously described model for the dynamics of the parasitic stages of Parascaris spp. was modified to include eggs outside the host and the genetics of anthelmintic resistance before being used to address questions regarding the development of resistance. Three broad questions were addressed; i) How sustainable is the current common practice of treating foals monthly for their first year of life (i.e. 12 treatments/year)? ii) Does the timing of treatments have an effect on resistance development? (i.e. do certain treatments select for resistance more strongly than others?), and iii) How sus...
Symons JE, Hawkins DA, Fyhrie DP, Upadhyaya SK, Stover SM.The metacarpophalangeal joint (fetlock) is the most commonly affected site of racehorse injury, with multiple observed pathologies consistent with extreme fetlock dorsiflexion. Race surface mechanics affect musculoskeletal structure loading and injury risk because surface forces applied to the hoof affect limb motions. Race surface mechanics are a function of controllable factors. Thus, race surface design has the potential to reduce the incidence of musculoskeletal injury through modulation of limb motions. However, the relationship between race surface mechanics and racehorse limb motions is...
Arbabi V, Pouran B, Weinans H, Zadpoor AA.Investigation of the solute transfer across articular cartilage and subchondral bone plate could nurture the understanding of the mechanisms of osteoarthritis (OA) progression. In the current study, we approached the transport of neutral solutes in human (slight OA) and equine (healthy) samples using both computed tomography and biphasic-solute finite element modeling. We developed a multi-zone biphasic-solute finite element model (FEM) accounting for the inhomogeneity of articular cartilage (superficial, middle and deep zones) and subchondral bone plate. Fitting the FEM model to the concentra...
Malekipour F, Oetomo D, Lee PV.Subchondral bone microdamage due to high-impact loading is a key factor leading to post-traumatic knee osteoarthritis. A quantified assessment of the mechanical characteristics of subchondral bone at the tissue-level is essential to study the mechanism of impact-induced microdamage. We combined mechanical impact testing of equine cartilage-bone with µCT image-based finite element models (μFEM) of each specimen to determine subchondral bone (including calcified cartilage: CCSB) elastic tissue modulus and local stresses and strains associated with micro-fractures within the CCSB tissue. The ma...
Symons JE, Hawkins DA, Fyhrie DP, Upadhyaya SK, Stover SM.Race surface mechanics contribute to musculoskeletal injury in racehorses. These mechanics affect ground reaction forces applied to the hoof, and thus limb motions during stance that can contribute to musculoskeletal pathologies. Race surface design has been largely empirical within the industry, with little uniform consensus for injury prevention and performance. Furthermore, race surface installations are too expensive to install experimentally. The objective of this research was to develop and evaluate an integrated racehorse limb and race surface computational model. Combined forward/inver...
Gan Z, Wiestner T, Weishaupt MA, Waldern NM, David Remy C.This paper presents a simplistic passive dynamic model that is able to create realistic quadrupedal walking, tölting, and trotting motions. The model is inspired by the bipedal spring loaded inverted pendulum (SLIP) model and consists of a distributed mass on four massless legs. Each of the legs is either in ground contact, retracted for swing, or is ready for touch down with a predefined angle of attack. Different gaits, that is, periodic motions differing in interlimb coordination patterns, are generated by choosing different initial model states. Contact patterns and ground reaction forces...
O'Hare LM, Cox PG, Jeffery N, Singer ER.To improve understanding of the internal structure of the proximal phalanx (P1), response of the bone to load and possible relation to the pathogenesis of fractures in P1. Objective: To model the P1 and replicate the loads experienced by the bone in stance, walk, trot and gallop using finite element analysis. Methods: The geometry of the P1 was captured using micro-computed tomography (μCT) and was reconstructed in 3 dimensions. Values for material properties and forces experienced at stance, walk, trot and gallop were taken from the literature and were applied to the reconstructed model. Usi...
Cordes V, Gardemin M, Lüpke M, Seifert H, Borchers L, Staszyk C.Periodontal diseases occur frequently in equine dentistry and excessive strain in biological tissues is assumed to be a predisposing factor in their development. Finite element (FE) analysis enables strains and stresses occurring in the periodontium to be calculated and is a useful tool for testing this hypothesis. The current study aimed to establish reliable 3-D models from equine maxillary and mandibular cheek teeth for use in FE simulations, with particular attention to the detailed construction of the periodontal ligament (PDL). Age-related morphological aspects of the teeth and the perio...
Aljuffali IA, Brainard BM, Moore JN, Kwon S, Allen D, Robertson TP, Arnold RD.The purpose of this study was to determine the pharmacokinetics (PK) of the 5-HT(2A) receptor antagonist ketanserin in healthy adult horses, and to develop a computational model that could be used to optimize dosing. Plasma concentrations of ketanserin were determined using liquid chromatography with mass spectrometry after single and multiple intravenous administration in the horse. A two-compartment linear pharmacokinetic model described the plasma concentration-time profile of ketanserin after single and multiple doses in healthy horses; the terminal half-life was 11.5 h; steady-state volum...
Garner MG, Cowled B, East IJ, Moloney BJ, Kung N.To use modelling and epidemiological analyses to assess the effectiveness of control strategies employed during the equine influenza outbreak and determine if early vaccination might have had a beneficial effect. Methods: Transmission of infection was modelled using stochastic, spatial simulation, based on data from 16 regions in New South Wales and Queensland over the first month of the outbreak. Results: The model accurately represented the spread of infection in both space and time and showed that vaccination strategies would have reduced new infections by ∼60% and reduced the size of the...
Wullschleger L, Weisse B, Blaser D, Fürst AE.Four radii of different horses were tested in three-point bending and in pure torsion. Detailed finite element (FE) models of these long bones were established by means of computed-tomography (CT) images and tests simulated for both load cases. For the allocation of the local isotropic material stiffness, individual exponential functions were applied whose factor and exponent were determined solely by fitting them to the measured torsional stiffness and bending stiffness of the entire bones. These stiffness functions referring directly to the CT number and having exponents between 1.5 and 2 we...
Forero Rueda MA, Cui L, Gilchrist MD.Jockey head injuries, especially concussions, are common in horse racing. Current helmets do help to reduce the severity and incidences of head injury, but the high concussion incidence rates suggest that there may be scope to improve the performance of equestrian helmets. Finite element simulations in ABAQUS/Explicit were used to model a realistic helmet model during standard helmeted rigid headform impacts and helmeted head model University College Dublin Brain Trauma Model (UCDBTM) impacts. Current helmet standards for impact determine helmet performance based solely on linear acceleration....
Garner MG, Cowled B, East IJ, Moloney BJ, Kung NY.In August 2007, Australia which had previously been free of equine influenza, experienced a large outbreak that lasted approximately 4 months before it was eradicated. The outbreak required a significant national response by government and the horse industries. The main components of the response were movement controls, biosecurity measures, risk-based zoning and, subsequently, vaccination to contain the outbreak. Although not initially used, vaccination became a key element in the eradication program, with approximately 140000 horses vaccinated. Vaccination is recognised as a valuable tool fo...
Thomason JJ, McClinchey HL, Faramarzi B, Jofriet JC.The horse's hoof is structurally modified for its mechanical functions, but studying the functional design of internal structures is hampered by the external keratinous capsule. Finite-element analysis offers one method for evaluating mechanical function of components within the capsule, such as the laminar junction. This is the epidermodermal connection that binds the hoof wall strongly to the distal phalanx. Primary epidermal laminae (PEL), projecting inward from the wall, vary in morphology and are remodeled despite being keratinous. The aim of this study is to investigate the suggestion th...
Thomason JJ, McClinchey HL, Jofriet JC.Finite-element (FE) methods have great potential in equine biomechanics in evaluating mechanical stresses and strains in tissues deep within the hoof. In this study, we critically assessed that potential by comparing results of FE analyses of capsular strain with in vivo data. Nine FE models were developed, corresponding to the shape of hooves for which in vivo principal strain data are available. Each model had the wall, laminar junction, sole and distal phalanx (PIII). In a first loading condition (LC1), force is distributed uniformly to the bearing surface of the wall to determine reaction ...
Hinterhofer C, Stanek C, Haider H.A finite element (FE) hoof capsule was built as a small, symmetrical forelimb hoof on IDEAS* as a model for calculation and visualisation of stress and displacement of the equine hoof capsule. The model's loading was performed according to the suspension of the coffin bone within the hoof wall (pulling force) and over the sole and frog (compressing force) with a total of 3000 N. Restraints of the model's ground nodes and surface wall nodes were defined for simulation of 4 shoeing situations: a regular horseshoe, a horseshoe with a toe clip, a horseshoe with regular side clips and a horseshoe w...
Pellegrini M, Corda M, Manca L, Olianas A, Sanna MT, Fais A, De Rosa MC, Bertonati C, Masala B, Giardina B.A study was made of the haemoglobin (Hb) system from the Sardinian dwarf horse (Equus caballus jara), one of the last surviving wild horse species in Europe. The oxygen binding properties of the whole haemolysate and of the four different horse Hbs, separated by ion-exchange chromatography, were studied with special regard to the effect of chloride, 2,3-diphosphoglycerate and lactate. Results indicate that no significant functional differences exist between the four Hb components of horse haemolysate. Moreover, the molecular basis of the intrinsically low oxygen affinity and of the weak intera...
Chu KK, Wang N, Stanley S, Cohen ND.The pharmacokinetic behavior of furosemide concentrations in performance horses is of great interest to the equine industry and equine researchers. Specifically, such information is useful for the evaluation of the existing guidelines in several racing jurisdictions and for the possible development of new guidelines for varying time periods after administration. We studied several approaches within the framework of nonlinear mixed effects models to increase the accuracy of evaluating these guidelines. Theoretical properties of the proposed methods were examined and the variances of the resulti...
Hinterhofer C, Stanek C, Haider H.The biomechanical effects of lowering and raising the heels were studied using a finite element (FE) computer model of the equine hoof capsule consisting of 18,635 finite elements. A static load of 3000 N was distributed to nodes of the inner hoof wall (80%) according to the suspension of the coffin bone, 20% loaded sole and frog. When loaded the FE hoof capsules showed the following deformations: the proximal dorsal wall moves back, the quarters flare to the side and sole and frog perform a downward movement. Stresses are high in the material surrounding the quarter nails, in the heels and in...
Schroter RC, Leeming A, Denny E, Bharath A, Marlin DJ.Recently we proposed that exercise-induced pulmonary haemorrhage (EIPH) results from locomotory-impact-induced trauma by impact of the scapula on the chest wall during footfall and the consequent transmission of waves through the lung. A computational model has been developed to demonstrate that wave amplification and focusing occur in the dorsocaudal tip of the lung for waves originating on the anterior subscapular surface. The propagation of an acoustic wave was investigated in a simplified 2-dimensional representation of a vertical anterio-dorsal section of horse lung. It was demonstrated t...
Newlyn HA, Collins SN, Cope BC, Hopegood L, Latham RJ, Reilly JD.A finite element model of donkey hoof wall was constructed from measurements taken directly from the hoof capsule of the left forefoot. The model was created with a 2 mm mesh and consisted of 11,608 nodes. A linear elastic analysis was conducted assuming isotropic material properties in response to a 375 newton (N) load, to simulate static loading. The load was applied to the wall via 400 laminae in order to simulate the way in which the pedal bone is suspended within the donkey hoof capsule. Displacement, stress concentration, principal strain, and force distribution across the hoof wall were...
Vorstenbosch MA, Buchner HH, Savelberg HH, Schamhardt HC, Barneveld A.To study the role of head movements in lame horses. Methods: 11 Dutch Warmblood horses. Methods: A 2-segment 2-dimensional inverse dynamic model of trotting horses was developed: trunk and head/neck segment joined in a neck joint. Model input consisted of averaged segmental inertial properties and averaged kinematic data, taken from 11 horses, trotting on a treadmill (3.5 m/s) in 3 conditions of induced lameness: sound, mildly lame, and moderately lame. Dynamic and static effects were analyzed. Results: Dynamic effects were found to be considerably larger than static effects. In the moderately...
Les CM, Keyak JH, Stover SM, Taylor KT.Three-dimensional finite element (FE) models of the left metacarpi of five adult horses were developed from quantitative computed tomography data, using the algorithms of Keyak et al. (1990, J Biomed. Engng 12, 389-397). The metacarpi were then equipped with 12 rosette strain gauges and loaded non-destructively in a mechanical testing machine. The bones and the models were loaded in axial compression, with the load evenly distributed across the distal row of carpal bones, and with a point load placed mediad to the sagittal midline, to a load equivalent to three times body weight (-15 kN); and ...
Giguère S, Sweeney RW, Bélanger M.To investigate the pharmacokinetics of enrofloxacin in adult horses. Methods: 2-dose oral and i.v. cross-over trial followed by multiple oral doses. Methods: 8 clinically normal adult horses. Methods: Enrofloxacin was administered at dosages of 2.5 mg/kg of body weight to 4 horses and 5.0 mg/kg to 4 other horses. Each dose was given by the intragastric and i.v. routes, using a cross-over design. After the first intragastric dose, 5 additional doses were administered at 12-hour intervals. Enrofloxacin concentrations were measured in serum, synovial fluid, peritoneal fluid, urine, CSF, and endom...
Richardson JD, Cripps PJ, Lane JG.The prediction of the age of a horse from its dentition has been widely accepted as an accurate technique, but recent reports have questioned this belief. In this study the dental features of 434 thoroughbreds of known age were documented and a multiple regression equation was calculated from the 13 dental features which had the highest correlation with true age. The accuracy of the ages assessed by a computer model were compared with the ages estimated by experienced equine clinicians. There was little difference between the accuracy of the computer model and the human observers, and neither ...
Thomas DA, Furman PA.The reverse transcriptase of Equine Infectious Anemia Virus (EIAV) was partially purified from virus particles and appeared to be a heterodimer with subunit molecular masses of 70 kdal and 59 kdal. The polymerase activity of this enzyme had an absolute requirement for a divalent cation, preferring Mg++ over Mn++. Addition of a monovalent cation to the reaction mixture enhanced, but was not required for enzyme activity. Kinetically, the reverse transcriptase of EIAV is similar to the reverse transcriptase of Human Imunodeficiency Virus Type 1 (HIV-1). Both enzymes have similar Km values for 2'-...
Newlyn HA, Collins SN, Cope BC, Hopegood L, Latham RJ, Reilly JD.A finite element model of donkey hoof wall was constructed from measurements taken directly from the hoof capsule of the left forefoot. The model was created with a 2 mm mesh and consisted of 11,608 nodes. A linear elastic analysis was conducted assuming isotropic material properties in response to a 375 newton (N) load, to simulate static loading. The load was applied to the wall via 400 laminae in order to simulate the way in which the pedal bone is suspended within the donkey hoof capsule. Displacement, stress concentration, principal strain, and force distribution across the hoof wall were...
Wang L, Zhang W, Wang C, Meng F, Du W, Wang T.In this study, the configuration of a bionic horse robot for equine-assisted therapy is presented. A single-leg system with two degrees of freedom (DOFs) is driven by a cam-linkage mechanism, and it can adjust the span and height of the leg end-point trajectory. After a brief introduction on the quadruped bionic horse robot, the structure and working principle of a single-leg system are discussed in detail. Kinematic analysis of a single-leg system is conducted, and the relationships between the structural parameters and leg trajectory are obtained. On this basis, the pressure angle characteri...
Vera L, Campos Arias D, Muylle S, Stergiopulos N, Segers P, van Loon G.Arterial rupture in horses has been observed during exercise, after phenylephrine administration or during parturition (uterine artery). In human pathophysiological research, the use of computer models for studying arterial hemodynamics and understanding normal and abnormal characteristics of arterial pressure and flow waveforms is very common. The objective of this research was to develop a computer model of the equine arterial circulation, in order to study local intra-arterial pressures and flow dynamics in horses. Morphologically, large differences exist between human and equine aortic arc...
Les CM, Keyak JH, Stover SM, Taylor KT.Three-dimensional finite element (FE) models of the left metacarpi of five adult horses were developed from quantitative computed tomography data, using the algorithms of Keyak et al. (1990, J Biomed. Engng 12, 389-397). The metacarpi were then equipped with 12 rosette strain gauges and loaded non-destructively in a mechanical testing machine. The bones and the models were loaded in axial compression, with the load evenly distributed across the distal row of carpal bones, and with a point load placed mediad to the sagittal midline, to a load equivalent to three times body weight (-15 kN); and ...
Aljuffali IA, Brainard BM, Moore JN, Kwon S, Allen D, Robertson TP, Arnold RD.The purpose of this study was to determine the pharmacokinetics (PK) of the 5-HT(2A) receptor antagonist ketanserin in healthy adult horses, and to develop a computational model that could be used to optimize dosing. Plasma concentrations of ketanserin were determined using liquid chromatography with mass spectrometry after single and multiple intravenous administration in the horse. A two-compartment linear pharmacokinetic model described the plasma concentration-time profile of ketanserin after single and multiple doses in healthy horses; the terminal half-life was 11.5 h; steady-state volum...
Chu KK, Wang N, Stanley S, Cohen ND.The pharmacokinetic behavior of furosemide concentrations in performance horses is of great interest to the equine industry and equine researchers. Specifically, such information is useful for the evaluation of the existing guidelines in several racing jurisdictions and for the possible development of new guidelines for varying time periods after administration. We studied several approaches within the framework of nonlinear mixed effects models to increase the accuracy of evaluating these guidelines. Theoretical properties of the proposed methods were examined and the variances of the resulti...
Akbari Shahkhosravi N, Kakavand R, Davies HMS, Komeili A.The health and performance of horses are significantly affected by diseases associated with the hoof. Laminitis is a critical hoof disease that causes pain and, potentially, severe hoof and bone pathology. Objective: To generate an equine hoof finite element (FE) model to investigate the impact of normal and toe-in hoof conformations on the degeneration (decrease in elastic modulus) of the laminar junction (LJ), as occurs in chronic laminitis. Methods: Computer software modelling. Methods: A hoof FE model was generated to investigate the biomechanics of hoof laminitis. A 3D model, consisting o...
Wullschleger L, Weisse B, Blaser D, Fürst AE.Four radii of different horses were tested in three-point bending and in pure torsion. Detailed finite element (FE) models of these long bones were established by means of computed-tomography (CT) images and tests simulated for both load cases. For the allocation of the local isotropic material stiffness, individual exponential functions were applied whose factor and exponent were determined solely by fitting them to the measured torsional stiffness and bending stiffness of the entire bones. These stiffness functions referring directly to the CT number and having exponents between 1.5 and 2 we...
Nielsen MK, Sauermann CW, Leathwick DM.Anthelmintic resistance is widespread in equine cyathostomin populations across the world, and with no new anthelmintic drug classes in the pharmaceutical pipeline, the equine industry is forced to abandon traditional parasite control regimens. Current recommendations aim at reducing treatment intensity and identifying high strongylid egg shedders in a targeted treatment approach. But, virtually nothing is known about the effectiveness of these recommendations, nor their applicability to different climatic regions, making it challenging to tailor sustainable recommendations for equine parasite...
Lee AKK, Uhl EW, Osborn ML.Therapies based upon whole-body biomechanical assessments are successful for injury prevention and rehabilitation in human athletes. Similar approaches have rarely been used to study equine athletic injury. Degenerative osteoarthritis caused by mechanical stress can originate from chronic postural dysfunction, which, because the primary dysfunction is often distant from the site of tissue injury, is best identified through modeling whole-body biomechanics. To characterize whole-body equine kinematics, a realistic skeletal model of a horse was created from equine computed tomography (CT) data t...
Yamada T, Aoi S, Adachi M, Kamimura T, Higurashi Y, Wada N, Tsuchiya K, Matsuno F.Horses use the transverse gallop in high-speed running. However, different animals use different gaits, and the gait preference of horses remains largely unclear. Horses have fore-aft asymmetry in their body structure and their center of mass (CoM) is anteriorly located far from the center of the body. Since such a CoM offset affects the running dynamics, we hypothesize that the CoM offset of horses is important in gait selection. In order to verify our hypothesis and clarify the gait selection mechanisms by horses from a dynamic viewpoint, we developed a simple model with CoM offset and inves...
Lescun TB, Adams SB, Main RP, Nauman EA, Breur GJ. The objectives of this study were to validate a finite element model of the equine distal limb transfixation cast and to determine the effect of six transcortical pin parameters on bone-pin interface (BPI) stresses in the third metacarpal bone. Methods: A transfixation cast finite element model was developed from a computed tomography scan of the third metacarpal bone and modelled pin elements. The model was validated by comparing strain measured around a 6.3-mm transfixation pin in the third metacarpal bone with the finite element model. The pin parameters of diameter, number, location,...
Adachi M, Aoi S, Kamimura T, Tsuchiya K, Matsuno F.Quadrupedal mammals have fore-aft asymmetry in their body structure, which affects their walking and running dynamics. However, the effects of asymmetry, particularly in the transverse plane, remain largely unclear. In this study, we examined the effects of fore-aft asymmetry on quadrupedal trotting in the transverse plane from a dynamic viewpoint using a simple model, which consists of two rigid bodies connected by a torsional joint with a torsional spring and four spring legs. Specifically, we introduced fore-aft asymmetry into the model by changing the physical parameters between the fore a...
Zellmann P, Ribitsch I, Handschuh S, Peham C.We developed a finite element model (FEM) of the equine stifle joint to identify pressure peaks and simulate translocation and deformation of the menisci. A series of sectional magnetic resonance images (1.5 T) of the stifle joint of a 23 year old Shetland pony gelding served as basis for image segmentation. Based on the 3D polygon models of femur, tibia, articular cartilages, menisci, collateral ligaments and the meniscotibial ligaments, an FEM model was generated. Tissue material properties were assigned based on data from human (Open knee(s) project) and bovine femoro-tibial joint available...
Martin LM, Bukoski AD, Whelchel DD, Evans TJ, Wiedmeyer CE, Black SJ, Johnson PJ.Pharmacokinetics of lithium chloride (LiCl) administered as a bolus, once i.v. have not been determined in horses. There is no point-of-care test to measure lithium (Li ) concentrations in horses in order to monitor therapeutic levels and avoid toxicity. Objective: To determine the pharmacokinetics of LiCl in healthy adult horses and to compare agreement between two methods of plasma Li concentration measurement: spectrophotometric enzymatic assay (SEA) and inductively coupled plasma mass spectrometry (ICP-MS). Methods: Nonrandomised, single exposure with repeated measures over time. Methods: ...
Houck EL, Papich MG, Delk KW.Southern white rhinoceros (Ceratotherium simum simum) frequently develop painful conditions, such as traumatic injuries or osteoarthritis, necessitating the administration of pain-relieving medications. One of the preferred treatments is the nonsteroidal anti-inflammatory drug phenylbutazone because of the availability of oral formulations and the familiarity of its use in horses. For the main study, a single oral dose of phenylbutazone at 2 mg/kg was administered to healthy adult rhinoceros (n = 33) housed at six North American zoological institutions. Each rhinoceros had up to four blood ...
Pagliara E, Pasinato A, Valazza A, Riccio B, Cantatore F, Terzini M, Putame G, Parrilli A, Sartori M, Fini M, Zanetti EM, Bertuglia A.A catastrophic fracture of the radial carpal bone experienced by a racehorse during a Palio race was analyzed. Computational modelling of the carpal joint at the point of failure informed by live data was generated using a multibody code for dynamics simulation. The circuit design in a turn, the speed of the animal and the surface characteristics were considered in the model. A macroscopic examination of the cartilage, micro-CT and histology were performed on the radio-carpal joint of the limb that sustained the fracture. The model predicted the points of contact forces generated at the level ...
Gan Z, Wiestner T, Weishaupt MA, Waldern NM, David Remy C.This paper presents a simplistic passive dynamic model that is able to create realistic quadrupedal walking, tölting, and trotting motions. The model is inspired by the bipedal spring loaded inverted pendulum (SLIP) model and consists of a distributed mass on four massless legs. Each of the legs is either in ground contact, retracted for swing, or is ready for touch down with a predefined angle of attack. Different gaits, that is, periodic motions differing in interlimb coordination patterns, are generated by choosing different initial model states. Contact patterns and ground reaction forces...
Oda D, Onogi A.The inheritance of racing performance in Thoroughbreds is of interest to breeders and geneticists. Therefore, the genetic parameters of racing performance have been investigated in various populations of Thoroughbreds. However, the predictability of the racing performance of a racehorse has not been assessed well. In this study, we built mixed-effects models for Japanese Thoroughbreds and assessed their predictability of racing performance. We used the average velocity as an index of racing performance and treated each category of racecourse and distance as different traits. Model selection us...
Thomas DA, Furman PA.The reverse transcriptase of Equine Infectious Anemia Virus (EIAV) was partially purified from virus particles and appeared to be a heterodimer with subunit molecular masses of 70 kdal and 59 kdal. The polymerase activity of this enzyme had an absolute requirement for a divalent cation, preferring Mg++ over Mn++. Addition of a monovalent cation to the reaction mixture enhanced, but was not required for enzyme activity. Kinetically, the reverse transcriptase of EIAV is similar to the reverse transcriptase of Human Imunodeficiency Virus Type 1 (HIV-1). Both enzymes have similar Km values for 2'-...
Ripley NE, Gravatte HS, Britton LN, Davis SM, Perrin GM, Warner S, Rexroat EK, Vetter AL, Maron EES, Finnerty CA, Stanton V, Nielsen MK.Parascaris spp. infect foals worldwide and foals typically shed eggs in the feces from about three to six months of age, upon which natural immunity is incurred. High levels of anthelmintic resistance of Parascaris spp. are a global concern, and further understanding egg shedding patterns and fecal egg counting (FEC) data variability is of high importance. The aims of this study were to monitor Parascaris spp. egg shedding in untreated foals during 12-23 weeks of age, estimate sources of data variability, and assess precision of two ascarid FEC techniques. Fecal samples were collected weekly f...
White SJ, Couetil L, Richard EA, Marti E, Wilson PB.Severe asthma (SA) in horses, resembling human asthma, is a prevalent, debilitating allergic respiratory condition marked by elevated allergen-specific immunoglobulin E (IgE) against environmental proteins; however, research exploring the exposome's influence on IgE profiles is currently limited but holds paramount significance for diagnostic and therapeutic developments. Methods: Thirty-five sports horses were analyzed, consisting of environmentally matched samples from France (5 SA; 6 control), the United States (6 SA; 6 control), and Canada (6 SEA; 6 control). Methods: This intentional cros...
Ask K, Rhodin M, Rashid-Engström M, Hernlund E, Andersen PH.A number of facial expressions are associated with pain in horses, however, the entire display of facial activities during orthopedic pain have yet to be described. The aim of the present study was to exhaustively map changes in facial activities in eight resting horses during a progression from sound to mild and moderate degree of orthopedic pain, induced by lipopolysaccharides (LPS) administered in the tarsocrural joint. Lameness progression and regression was measured by objective gait analysis during movement, and facial activities were described by EquiFACS in video sequences (n = 348...
Verdegaal EJMM, Howarth GS, McWhorter TJ, Delesalle CJG.Hyperthermia and exertional heat illness (EHI) are performance and welfare issues for all exercising horses. Monitoring the thermoregulatory response allows for early recognition of metabolic heat accumulation during exercise and the possibility of taking prompt and effective preventative measures to avoid a further increase in core body temperature (Tc) leading to hyperthermia. Skin temperature (Tsk) monitoring is most used as a non-invasive tool to assess the thermoregulatory response pre- and post-exercise, particularly employing infrared thermographic equipment. However, only a few studies...
Marín Navas C, Delgado Bermejo JV, McLean AK, León Jurado JM, Camacho Vallejo ME, Navas González FJ.The historical increase in the occurrence of extreme weather events in Spain during the last thirty years makes it a perfect location for the evaluation of climate change. Modeling the effects of climate change on domestic animals' genetic diversity may help to anticipate challenging situations. However, animal populations' short life cycle and patent lack of historical information during extended periods of time drastically compromise the evaluation of climate change effects. Locally adapted breeds' gene pool is the base for their improved resilience and plasticity in response to climate chan...
Toutain PL.Population pharmacokinetics (POP PK) is a powerful pharmacokinetic tool, which measures quantitatively, and explains the variability in drug exposure and drug effect between individuals. POP PK uses an observational (nonexperimental) approach; it is conducted in the target population living in its normal environment (e.g., farm and race-track). The strength of the POP PK approach lies in its greater relevance for the population studied in its different natural environments than experimental studies carried out in more or less biased laboratory conditions. In clinical settings, it is commonly n...
