Simulation and horses involve the use of computational and virtual models to study and analyze equine behavior, physiology, and biomechanics. These simulations can replicate various scenarios, such as movement patterns, training regimens, and environmental interactions, to better understand horse dynamics and performance. Applications of equine simulations include optimizing training programs, improving rehabilitation strategies, and enhancing rider-horse communication. This page gathers peer-reviewed research studies and scholarly articles that explore the development, validation, and applications of simulation models in equine science.
Vernemmen I, Demeyere M, Van Steenkiste G, Buschmann E, Decloedt A, van Loon G.Ultrasonographic guidance of catheter-based interventions in horses is based primarily on transthoracic echocardiography (TTE). Intracardiac echocardiography (ICE) has the potential to provide detailed imaging of specific cardiac regions. Insight and training in echocardiographic guidance can be acquired using an echocardiography simulator. Objective: Use an echocardiography simulator for horses to determine specific ICE views for catheter-based interventions and validate these in live horses. Methods: Six adult healthy experimental horses. Methods: Observational study. An echocardiographic ph...
Coutinho GH, Ragle CA.The objective of this demonstration was to describe and simulate a surgical technique for removing subepiglottic cysts in horses via an oral approach under endoscopic guidance using a cadaver model for simulation and clinical data. The technique aims to provide a minimally invasive method for the removal of these cysts. Methods: 2 clinical case images from the Washington State University Teaching Hospital were used in the video. In a third horse euthanized for reasons unrelated to the study, the procedure was simulated after the head was frozen and transected transversally. Methods: Files from...
Kuroda T, Minamijima Y, Niwa H, Mita H, Tamura N, Fukuda K, Toutain PL, Ohta M.Fosfomycin (FOM) is an approved veterinary medicinal product for large animals in Japan, but Clinical breakpoint (CBP) for antimicrobial susceptibility test (AST) is not defined for animals. This study aimed at conducting a pharmacokinetics/pharmacodynamics (PK/PD) analysis to determine the PK/PD cutoff for the CBP in horses. Drug concentrations following single intravenous administration (IV) of 20 mg/kg body weight (BW) FOM in nine horses were measured using liquid chromatography/mass spectrometry. The data were modelled using a nonlinear mixed-effects model, followed by Monte Carlo simulati...
Bronstein A, Marx A.Comparison of myoglobin structures reveals that protein isolated from horse heart consistently adopts an alternate turn conformation in comparison to its homologues. Analysis of hundreds of high-resolution structures discounts crystallization conditions or the surrounding amino acid protein environment as explaining this difference, that is also not captured by the AlphaFold prediction. Rather, a water molecule is identified as stabilizing the conformation in the horse heart structure, which immediately reverts to the whale conformation in molecular dynamics simulations excluding that structur...
Prutton AM, Lenaghan HAH, Baillie S.Simulation in veterinary education is an important means of providing a safe, welfare-friendly way for students to hone their skills prior to performing procedures on live animals. Students may not get many chances to practice passing a nasogastric tube and checking for reflux in live horses during clinical rotations and extra-mural studies. A low-cost equine nasogastric intubation model was created at the University of Surrey, allowing students to practice passing a tube and checking for reflux. Thirty-two equine veterinarians evaluated the model for realism, and its potential usefulness in t...
Kuroda T, Minamijima Y, Mita H, Tamura N, Fukuda K, Kuwano A, Toutain PL, Sato F.A pharmacokinetics/pharmacodynamics (PK/PD) approach was used to determine the best empirical dosage regimen of cefazolin (CEZ) after intramuscular (IM) administration of CEZ in horses. Seven horses received a single IM or intravenous (IV) administration of CEZ of 5 mg/kg bodyweight (BW) according to a crossover design. CEZ plasma concentrations were measured using LC-MS/MS. The plasma concentrations in these seven horses and those of six other horses obtained in a previous study with an IV CEZ dose of 10 mg/kg were modelled simultaneously using NonLinear Mixed-Effect modelling followed by M...
Sterkenburgh T, Schulz-Kornas E, Nowak M, Staszyk C.Equine mastication, as well as dental wear patterns, is highly important for the development of treatments in equine dentistry. During the last decades, the stress and strain distributions of equine teeth have been successfully simulated using finite element analysis. Yet, to date, there is no simulation available for dental tooth wear in equines. In this study, we developed a simplified two-dimensional computer simulation of dental wear. It provides a first tentative explanation for the development of the marked physiological inclination of the occlusal surface and for pathological conditions...
Kuroda T, Minamijima Y, Nomura M, Yamashita S, Yamada M, Nagata S, Mita H, Tamura N, Fukuda K, Kuwano A, Kusano K, Toutain PL, Sato F.For medication control in several jurisdictions, withdrawal time is the period of refrain from racing after drug administration. It is set by adding a safety period to an experimental detection time. However, there are no reports of statistical analyses of detection time for the determination of withdrawal time in flunixin meglumine-treated horses. Objective: To analyse the population pharmacokinetics of flunixin in horses through the generation of a dataset for detection time statistical analysis and predictions via Monte Carlo simulation. Methods: Experimental study. Methods: Drug plasma and...
Lupala CS, Kumar V, Su XD, Wu C, Liu H.The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 pandemic. Angiotensin-converting enzyme 2 (ACE2) has been identified as the host cell receptor that binds to the receptor-binding domain (RBD) of the SARS-COV-2 spike protein and mediates cell entry. Because the ACE2 proteins are widely available in mammals, it is important to investigate the interactions between the RBD and the ACE2 of other mammals. Here we analyzed the sequences of ACE2 proteins from 16 mammals, predicted the structures of ACE2-RBD complexes by homology modeling, and refi...
Chardonnet JR, Ryard J, Secheppet M, Benezet C, Azema G, Leblanc S.Animal welfare has become an increasingly important concern in the sports field. Learning horse-drawn carriage driving requires much time and effort for both the drivers and the horses because the associated gestures to avoid harming the horses are difficult to acquire. This raises the need to develop realistic simulation environments for future drivers. To this end, two haptic interface prototypes were designed, coupled with dedicated simulation software. The first was developed based on a SPIDAR haptic device and implemented simple behaviors of the carriage. A user study demonstrated interes...
Arias KD, Cervantes I, Gutiérrez JP.In genetic evaluation of horses, the genetic trend does not correspond into a phenotypic trend when using ranking as a phenotype due to its uniform distribution, and some other effects might be absorbing that trend. From a founder population, a further four discrete generations of 100 individuals were simulated under random mating. Then, ten additional discrete generations were simulated by selecting the best 10% of the animals. Likewise, an underlying variable with heritability 0.1 or 0.2, affected by an event environmental influence, generation and permanent environment, was simulated to est...
Schenk I, Machnik M, Broussou D, Meuly A, Roques BB, Lallemand E, Düe M, Röttgen H, Lagershausen H, Toutain PL, Thevis M.In horses, the benzodiazepine diazepam (DIA) is used as sedative for pre-medication or as an anxiolytic to facilitate horse examinations. As the sedative effects can also be abused for doping purposes, DIA is prohibited in equine sports. DIA is extensively metabolized to several active metabolites such as nordazepam, temazepam and oxazepam (OXA). For veterinarians, taking into account the detection times of DIA and its active metabolites is needed for minimizing the risk of an anti-doping rule violation. Therefore, a pharmacokinetic study on 6 horses was conducted using a single intravenous (...
Makhaeva GF, Lushchekina SV, Kovaleva NV, Yu Astakhova T, Boltneva NP, Rudakova EV, Serebryakova OG, Proshin AN, Serkov IV, Trofimova TP, Tafeenko VA....We synthesized eleven new amiridine-piperazine hybrids 5a-j and 7 as potential multifunctional agents for Alzheimer's disease (AD) treatment by reacting N-chloroacetylamiridine with piperazines. The compounds displayed mixed-type reversible inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Conjugates were moderate inhibitors of equine and human BChE with negligible fluctuation in anti-BChE activity, whereas anti-AChE activity was substantially dependent on N4-substitution of the piperazine ring. Compounds with para-substituted aromatic moieties (5g, 5h, and bis-amirid...
Mure S, Oishi K, Hirooka H.The objective of the present study was to develop a deterministic simulation model for evaluating the reproductive performance of Thoroughbred mares. As an application, the model was used to estimate the herd level asymptotic foaling percentage (AFP) for evaluating the performance of mares in stabilized mare herds using the convergent method for estimating a steady-state distribution of mares. In this model, it was assumed that the mares were mated only during the breeding season. The effects of early pregnancy loss and fetal loss on reproductive performance were investigated. The sensitivitie...
Bousquet-Mélou A, Schneider M, El Garch F, Broussou DC, Ferran AA, Lallemand EA, Triboulloy C, Damborg P, Toutain PL.Marbofloxacin (MBX), a fluoroquinolone (FQ), is considered as a critical antibiotic requiring antimicrobial susceptibility testing (AST) for prudent use. No clinical breakpoint (CBP) currently exists to interpret the results of such tests in horses. Objective: To compute PK/PD cut-offs (PK/PDCO ) that is one of the three minimum inhibitory concentrations (MICs) considered establishing a CBP for antimicrobial susceptibility test interpretation. Methods: A meta-analysis conducted by combining five sets of previously published pharmacokinetic data, obtained in clinical and nonclinical settings. M...
Du H, Yousefian O, Horn T, Muller M.The mode-converted (longitudinal to transverse, L-T) ultrasonic scattering method was utilized to characterize the structural anisotropy of a phantom mimicking the structural properties of trabecular bone. The sample was fabricated using metal additive manufacturing from high-resolution computed tomography (CT) images of a sample of trabecular horse bone with strong anisotropy. Two focused transducers were used to perform the L-T ultrasonic measurements. A normal incidence transducer was used to transmit longitudinal ultrasonic waves into the sample, while the scattered transverse signals were...
Nassar M.The present longitudinal study ascertained training-associated transformations in the neural underpinnings of diagnostic reasoning, using a simulation game named "Equine Virtual Farm" (EVF). Twenty participants underwent structural, EVF/task-based and resting-state MRI and diffusion tensor imaging (DTI) before and after completing their training on diagnosing simulated veterinary cases. Comparing playing veterinarian versus seeing a colorful image across training sessions revealed the transition of brain activity from scientific creativity regions pre-training (left middle frontal and temporal...
Beaulieu A, Linden AZ, Phillips J, Arroyo LG, Koenig J, Monteith G.In the equine racehorse industry, reduced athletic performance due to joint injury and lameness has been extensively reviewed. Intra-articular injections of glucocorticoids are routinely used to relieve pain and inflammation associated with osteoarthritis. Intra-articular injections of pharmaceutical agents require practice for precise needle placement and to minimize complications. Training on simulators or models is a viable alternative for developing these technical skills. The purpose of this study was to compare the qualitative ultrasonographic characteristics of three-dimensional (3D) pr...
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...
Elarbi MM, Ragle CA, Fransson BA, Farnsworth KD.OBJECTIVE To develop and validate a simulation model for laparoscopic ovariectomy in standing horses. DESIGN Prospective cohort study. SAMPLE 15 third-year veterinary students and 4 equine surgeons with experience in laparoscopy. PROCEDURES A simulation model that mimicked laparoscopic ovariectomy in standing horses was developed. Face validity of the model was determined with a questionnaire completed by the equine surgeons. Construct validity was determined by comparing performance scores (based on time to completion and accuracy completing various operative tasks) for simulated laparoscopic...
Tong KJ, Duchêne DA, Duchêne S, Geoghegan JL, Ho SYW.Phylogenetic analysis of DNA from modern and ancient samples allows the reconstruction of important demographic and evolutionary processes. A critical component of these analyses is the estimation of evolutionary rates, which can be calibrated using information about the ages of the samples. However, the reliability of these rate estimates can be negatively affected by among-lineage rate variation and non-random sampling. Using a simulation study, we compared the performance of three phylogenetic methods for inferring evolutionary rates from time-structured data sets: regression of root-to-tip...
Spence KL, O'Sullivan TL, Poljak Z, Greer AL.On-farm biosecurity measures are an important part of a control plan to minimize the introduction and spread of infectious diseases, such as equine influenza, in an equine facility. It can be challenging, however, to evaluate the efficacy of biosecurity measures under field conditions. We used an agent-based computer simulation model to describe the impact of: i) preventive vaccination; ii) reduced horse-to-horse contact; and iii) a combination of vaccination and reduced contact during an outbreak of equine influenza in a simulated horse facility. The model demonstrated that the most effective...
Spence KL, O'Sullivan TL, Poljak Z, Greer AL.Participation in equestrian shows provides opportunities for contact between horses, increasing the risk of disease introduction and spread within the population. The magnitude of a potential outbreak, and the impact of disease prevention and control strategies, can be estimated using simulation modeling. The objectives of this study were to (1) examine the potential spread of equine influenza in a network of horses associated with a 2-day equestrian show in Ontario, Canada; and (2) determine the effectiveness of several interventions during a simulated outbreak. A discrete-event, continuous-t...
Kim MJ, Kim T, Oh S, Yoon B.Horseback riding is an effective exercise for improving postural control and balance. To reduce costs and improve accessibility, simulated horseback riding has been developed; but no differential effects of simulated and real horseback riding on muscle activation patterns in older adults have been studied. Thus, we compared muscle activation patterns for older and younger adults engaged in real and simulated horseback riding exercises, using surface electromyography recordings of the erector spinae, rectus abdominis, internal oblique abdominis, and rectus femoris muscles. We recorded muscle ac...
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...
Tanase M, Ambe Y, Aoi S, Matsuno F.Among quadrupedal gaits, the galloping gait has specific characteristics in terms of locomotor behavior. In particular, it shows a left-right asymmetry in gait parameters such as touchdown angle and the relative phase of limb movements. In addition, asymmetric gait parameters show a characteristic dependence on locomotion speed. There are two types of galloping gaits in quadruped animals: the transverse gallop, often observed in horses; and the rotary gallop, often observed in dogs and cheetahs. These two gaits have different footfall sequences. Although these specific characteristics in quadr...
Jauch SY, Wallstabe S, Sellenschloh K, Rundt D, Püschel K, Morlock MM, Meenen NM, Huber G.Horse-related injuries are manifold and can involve the upper and lower limbs, the trunk, spine or head. Cervical spine injuries are not among the most common injuries. However, they can be fatal and often result in neurological symptoms. This study investigated the influence of the posture of the cervical spine on the ultimate strength and the pattern of vertebrae failure with the aim to provide some guidance for protective clothing design. Methods: Eighteen human cervical spines, each divided into two specimens (three vertebrae each), were subjected to a simulator test designed to mimic a sp...
Legarra A, Croiseau P, Sanchez MP, Teyssèdre S, Sallé G, Allais S, Fritz S, Moreno CR, Ricard A, Elsen JM.With dense genotyping, many choices exist for methods to detect quantitative trait loci (QTL) in livestock populations. However, no across-species study has been conducted on the performance of different methods using real data. We compared three methods that correct for relatedness either implicitly or explicitly: linkage and linkage disequilibrium haplotype-based analysis (LDLA), efficient mixed-model association (EMMA) analysis, and Bayesian whole-genome regression (BayesC). We analyzed one chromosome in each of five datasets (dairy cattle, beef cattle, sheep, horses, and pigs) using real g...
Rosanowski SM, Cogger N, Rogers CW, Stevenson MA.New Zealand has never experienced an equine influenza (EI) outbreak. The 2007 outbreak of EI in Australia showed that in a naïve population EI spreads rapidly and substantial efforts (in terms of movement restrictions, mass vaccination and post-vaccination surveillance) were required to achieve eradication. To control EI, it is essential that animal health authorities have well-defined strategies for containment, control and eradication in place before an incursion occurs. A spatially explicit stochastic simulation model, InterSpread Plus, was used to evaluate EI control strategies for the Ne...
Lopez BS, Giguère S, Berghaus LJ, Mullins MA, Davis JL.The objectives of this study were to investigate the pharmacokinetics of danofloxacin and its metabolite N-desmethyldanofloxacin and to determine their concentrations in synovial fluid after administration by the intravenous, intramuscular or intragastric routes. Six adult mares received danofloxacin mesylate administered intravenously (i.v.) or intramuscularly (i.m.) at a dose of 5 mg/kg, or intragastrically (IG) at a dose of 7.5 mg/kg using a randomized Latin square design. Concentrations of danofloxacin and N-desmethyldanofloxacin were measured by UPLC-MS/MS. After i.v. administration, da...
Band GP, van der Molen MW, Logan GD.In the stop-signal paradigm, subjects perform a standard two-choice reaction task in which, occasionally and unpredictably, a stop-signal is presented requiring the inhibition of the response to the choice signal. The stop-signal paradigm has been successfully applied to assess the ability to inhibit under a wide range of experimental conditions and in various populations. The current study presents a set of evidence-based guidelines for using the stop-signal paradigm. The evidence was derived from a series of simulations aimed at (a) examining the effects of experimental design features on in...
Anastasiou A, Hall LD.Cramer-Rao theory and computer simulations were used to show that the errors involved in calculating the magnetization and relaxation parameters of a two-component system decrease with: (1) increasing SNR, (2) increasing number of echoes used in the fitting procedure, and (3) increasing ratio of the relaxation times of the two components, T(22)/T(21). Images of bi-compartmental phantoms of known T(2) values were acquired using an optimized imaging sequence, and an optimized fitting algorithm was used to calculate the T(2) values of the two components by fitting the resulting images to a bi-exp...
Legarra A, Croiseau P, Sanchez MP, Teyssèdre S, Sallé G, Allais S, Fritz S, Moreno CR, Ricard A, Elsen JM.With dense genotyping, many choices exist for methods to detect quantitative trait loci (QTL) in livestock populations. However, no across-species study has been conducted on the performance of different methods using real data. We compared three methods that correct for relatedness either implicitly or explicitly: linkage and linkage disequilibrium haplotype-based analysis (LDLA), efficient mixed-model association (EMMA) analysis, and Bayesian whole-genome regression (BayesC). We analyzed one chromosome in each of five datasets (dairy cattle, beef cattle, sheep, horses, and pigs) using real g...
Wang HH, Kung NY, Grant WE, Scanlan JC, Field HE.Zoonoses from wildlife threaten global public health. Hendra virus is one of several zoonotic viral diseases that have recently emerged from Pteropus species fruit-bats (flying-foxes). Most hypotheses regarding persistence of Hendra virus within flying-fox populations emphasize horizontal transmission within local populations (colonies) via urine and other secretions, and transmission among colonies via migration. As an alternative hypothesis, we explore the role of recrudescence in persistence of Hendra virus in flying-fox populations via computer simulation using a model that integrates publ...
Makhaeva GF, Lushchekina SV, Kovaleva NV, Yu Astakhova T, Boltneva NP, Rudakova EV, Serebryakova OG, Proshin AN, Serkov IV, Trofimova TP, Tafeenko VA....We synthesized eleven new amiridine-piperazine hybrids 5a-j and 7 as potential multifunctional agents for Alzheimer's disease (AD) treatment by reacting N-chloroacetylamiridine with piperazines. The compounds displayed mixed-type reversible inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Conjugates were moderate inhibitors of equine and human BChE with negligible fluctuation in anti-BChE activity, whereas anti-AChE activity was substantially dependent on N4-substitution of the piperazine ring. Compounds with para-substituted aromatic moieties (5g, 5h, and bis-amirid...
Weng X, Cloutier G, Pibarot P, Durand LG.Erythrocyte aggregation levels in pig, horse, sheep, and calf blood samples were investigated and compared to that of normal human blood. The aggregation kinetics and adhesive forces between red cells, and an index of structure of the aggregates were determined with an erythroaggregameter (Regulest, France) at constant hematocrit (0.40 l/l) and temperature (37 degrees C). The adhesive forces and the index of structure in pig blood were close to those of normal human blood. The results for horse blood showed a very high level of aggregation kinetics and adhesive forces between red cells. For sh...
Tong KJ, Duchêne DA, Duchêne S, Geoghegan JL, Ho SYW.Phylogenetic analysis of DNA from modern and ancient samples allows the reconstruction of important demographic and evolutionary processes. A critical component of these analyses is the estimation of evolutionary rates, which can be calibrated using information about the ages of the samples. However, the reliability of these rate estimates can be negatively affected by among-lineage rate variation and non-random sampling. Using a simulation study, we compared the performance of three phylogenetic methods for inferring evolutionary rates from time-structured data sets: regression of root-to-tip...
van den Bogert AJ, Schamhardt HC, Crowe A.Locomotion of the horse is simulated using a mathematical model based on rigid body dynamics. A general method to generate the equations of motion for a two-dimensional rigid body model with an arbitrary number of hinge joints is presented and a numerical solution method, restricted to tree-structured models, is described. Joint movements originating from muscular forces or moments are simulated, but the method also allows that parts of the model follow strictly the pattern of kinematic data. Moment-generators with first-order linear feedback were used as a rotational muscle-equivalent. Ground...
Lupala CS, Kumar V, Su XD, Wu C, Liu H.The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 pandemic. Angiotensin-converting enzyme 2 (ACE2) has been identified as the host cell receptor that binds to the receptor-binding domain (RBD) of the SARS-COV-2 spike protein and mediates cell entry. Because the ACE2 proteins are widely available in mammals, it is important to investigate the interactions between the RBD and the ACE2 of other mammals. Here we analyzed the sequences of ACE2 proteins from 16 mammals, predicted the structures of ACE2-RBD complexes by homology modeling, and refi...
Gunther MR, Sturgeon BE, Mason RP.The reaction between metmyoglobin (metMb) and hydrogen peroxide has been known since the 1950s to produce globin-centered free radicals. The direct electron spin resonance spectrum of a solution of horse metMb and hydrogen peroxide at room temperature consists of a multilined signal that decays in minutes at room temperature. Comparison of the direct ESR spectra obtained from the system under N(2)- and O(2)-saturated conditions demonstrates the presence of a peroxyl radical, identified by its g-value of 2.014. Computer simulations of the spectra recorded 3 s after the mixture of metMb and H(2)...
Swanstrom MD, Zarucco L, Hubbard M, Stover SM, Hawkins DA.Because thoroughbred racehorses have a high incidence of forelimb musculoskeletal injuries, a model was desired to screen potential risk factors for injuries. This paper describes the development of a musculoskeletal model of the thoroughbred forelimb and a dynamic simulation of the motion of the distal segments during the stance phase of high-speed (18 m/s) gallop. The musculoskeletal model is comprised of segment, joint, muscle-tendon, and ligament information. The dynamic simulation incorporates a proximal forward-driving force, a distal ground reaction force model, muscle activations, and ...
Elarbi MM, Ragle CA, Fransson BA, Farnsworth KD.OBJECTIVE To develop and validate a simulation model for laparoscopic ovariectomy in standing horses. DESIGN Prospective cohort study. SAMPLE 15 third-year veterinary students and 4 equine surgeons with experience in laparoscopy. PROCEDURES A simulation model that mimicked laparoscopic ovariectomy in standing horses was developed. Face validity of the model was determined with a questionnaire completed by the equine surgeons. Construct validity was determined by comparing performance scores (based on time to completion and accuracy completing various operative tasks) for simulated laparoscopic...
Antosiewicz J, Porschke D.Hemoglobins from normal human cells, from sickle cells, and from horse were investigated by electrooptical methods in their oxy and deoxy forms. The reduced linear dichroism measured as a function of the electric field strength demonstrates the existence of permanent dipole moments in the range of 250-400 Debye units. The reduced limiting dichroism is relatively small (< or = 0.1); it is negative for hemoglobin from sickle cells and positive for the hemoglobins from normal human cells and from horse. The dichroism decay time constants are in the range from about 55 to 90 ns. Calculations of th...
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....
Beaulieu A, Linden AZ, Phillips J, Arroyo LG, Koenig J, Monteith G.In the equine racehorse industry, reduced athletic performance due to joint injury and lameness has been extensively reviewed. Intra-articular injections of glucocorticoids are routinely used to relieve pain and inflammation associated with osteoarthritis. Intra-articular injections of pharmaceutical agents require practice for precise needle placement and to minimize complications. Training on simulators or models is a viable alternative for developing these technical skills. The purpose of this study was to compare the qualitative ultrasonographic characteristics of three-dimensional (3D) pr...
Kim MJ, Kim T, Oh S, Yoon B.Horseback riding is an effective exercise for improving postural control and balance. To reduce costs and improve accessibility, simulated horseback riding has been developed; but no differential effects of simulated and real horseback riding on muscle activation patterns in older adults have been studied. Thus, we compared muscle activation patterns for older and younger adults engaged in real and simulated horseback riding exercises, using surface electromyography recordings of the erector spinae, rectus abdominis, internal oblique abdominis, and rectus femoris muscles. We recorded muscle ac...
Spence KL, O'Sullivan TL, Poljak Z, Greer AL.Participation in equestrian shows provides opportunities for contact between horses, increasing the risk of disease introduction and spread within the population. The magnitude of a potential outbreak, and the impact of disease prevention and control strategies, can be estimated using simulation modeling. The objectives of this study were to (1) examine the potential spread of equine influenza in a network of horses associated with a 2-day equestrian show in Ontario, Canada; and (2) determine the effectiveness of several interventions during a simulated outbreak. A discrete-event, continuous-t...
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...
Rosanowski SM, Cogger N, Rogers CW, Stevenson MA.New Zealand has never experienced an equine influenza (EI) outbreak. The 2007 outbreak of EI in Australia showed that in a naïve population EI spreads rapidly and substantial efforts (in terms of movement restrictions, mass vaccination and post-vaccination surveillance) were required to achieve eradication. To control EI, it is essential that animal health authorities have well-defined strategies for containment, control and eradication in place before an incursion occurs. A spatially explicit stochastic simulation model, InterSpread Plus, was used to evaluate EI control strategies for the Ne...
Tanase M, Ambe Y, Aoi S, Matsuno F.Among quadrupedal gaits, the galloping gait has specific characteristics in terms of locomotor behavior. In particular, it shows a left-right asymmetry in gait parameters such as touchdown angle and the relative phase of limb movements. In addition, asymmetric gait parameters show a characteristic dependence on locomotion speed. There are two types of galloping gaits in quadruped animals: the transverse gallop, often observed in horses; and the rotary gallop, often observed in dogs and cheetahs. These two gaits have different footfall sequences. Although these specific characteristics in quadr...
Bousquet-Mélou A, Schneider M, El Garch F, Broussou DC, Ferran AA, Lallemand EA, Triboulloy C, Damborg P, Toutain PL.Marbofloxacin (MBX), a fluoroquinolone (FQ), is considered as a critical antibiotic requiring antimicrobial susceptibility testing (AST) for prudent use. No clinical breakpoint (CBP) currently exists to interpret the results of such tests in horses. Objective: To compute PK/PD cut-offs (PK/PDCO ) that is one of the three minimum inhibitory concentrations (MICs) considered establishing a CBP for antimicrobial susceptibility test interpretation. Methods: A meta-analysis conducted by combining five sets of previously published pharmacokinetic data, obtained in clinical and nonclinical settings. M...
Newman JC, Prange T, Jennings S, Barlow BM, Davis JL.The objectives of this study were to examine the pharmacokinetics of tobramycin in the horse following intravenous (IV), intramuscular (IM), and intra-articular (IA) administration. Six mares received 4 mg/kg tobramycin IV, IM, and IV with concurrent IA administration (IV+IA) in a randomized 3-way crossover design. A washout period of at least 7 days was allotted between experiments. After IV administration, the volume of distribution, clearance, and half-life were 0.18 ± 0.04 L/kg, 1.18 ± 0.32 mL·kg/min, and 4.61 ± 1.10 h, respectively. Concurrent IA administration could not be...
Lord CC, Woolhouse ME, Mellor PS.A simulation model including two hosts (horses and donkeys) and one vector (Culicoides imicola) for African horse sickness in Spain is extended to consider vaccination strategies. If hosts were protected prior to virus introduction, elimination of simulated epidemics was related nonlinearly to the fraction protected. Protecting donkeys as well as horses increased the effectiveness of vaccination. Prevention of 50% of epidemics required 75% coverage of horses and donkeys or 90% coverage of horses only. Protection after the introduction of the virus was rarely successful in preventing outbreaks....
Sterkenburgh T, Schulz-Kornas E, Nowak M, Staszyk C.Equine mastication, as well as dental wear patterns, is highly important for the development of treatments in equine dentistry. During the last decades, the stress and strain distributions of equine teeth have been successfully simulated using finite element analysis. Yet, to date, there is no simulation available for dental tooth wear in equines. In this study, we developed a simplified two-dimensional computer simulation of dental wear. It provides a first tentative explanation for the development of the marked physiological inclination of the occlusal surface and for pathological conditions...
van den Bogert AJ, Schamhardt HC.Multi-body models of musculoskeletal systems can be used to determine internal forces from measured external forces and movements ('inverse dynamics') and to perform simulations of movements using muscle forces or activations as input ('direct dynamics'). Examples of 'direct' simulations of movements in the horse are presented. With a model of the equine hindlimb, the function of the 'passive stay apparatus' could be explained. A model of the forelimb was used to determine force distributions in the digital flexor tendons, and to experiment with various methods to change the force distribution...
Burns EM, Enns RM, Garrick DJ.We examined the impact of censored data on estimates of heritability of longevity. Longevity, defined as the length of productive racing life of an individual, is influenced by many factors. A simulated data set, modelled on the Irish Thoroughbred industry, was used to estimate heritabilities of longevity. Several scenarios representing various levels of censoring of performance data were created. The heritability of longevity was estimated for each scenario and compared to the estimated heritability of 0.120 for the complete data set. It was found that the estimates of heritability (0.107, 0....
Hitchens PL, Curry B, Blizzard CL, Palmer AJ.The profession of a horse-racing jockey is a dangerous one. We developed a decision tree model quantifying the effects of implementing different safety strategies on jockey fall and injury rates and their associated costs. Methods: Data on race-day falls were obtained from stewards' reports from August 2002 to July 2009. Insurance claim data were provided by Principal Racing Authorities and workers' compensation authorities in each jurisdiction. Fall and claim incidence data were used as baseline rates. The model considered (1) the status quo, in which policy was unchanged; and (2) compared it...
Nielsen MK, Vidyashankar AN, Hanlon BM, Diao G, Petersen SL, Kaplan RM.Anthelmintic resistance is an increasing challenge for the control of equine parasites. The fecal egg count reduction test (FECRT) is the practical gold standard method for evaluating reduction in anthelmintic efficacy, but the interpretation is complicated due to high levels of variability. A hierarchical statistical model was described for analysis of FECRT data from multiple farms to evaluate the role of biological factors in determining the strongyle efficacy of pyrantel pamoate in a study performed in Denmark. The model was then used to describe two notions of farm efficacy, namely condit...
Kuroda T, Minamijima Y, Nomura M, Yamashita S, Yamada M, Nagata S, Mita H, Tamura N, Fukuda K, Kuwano A, Kusano K, Toutain PL, Sato F.For medication control in several jurisdictions, withdrawal time is the period of refrain from racing after drug administration. It is set by adding a safety period to an experimental detection time. However, there are no reports of statistical analyses of detection time for the determination of withdrawal time in flunixin meglumine-treated horses. Objective: To analyse the population pharmacokinetics of flunixin in horses through the generation of a dataset for detection time statistical analysis and predictions via Monte Carlo simulation. Methods: Experimental study. Methods: Drug plasma and...
Brownstein AL, Read SJ, Simon D.These studies were designed to test cognitive dissonance theory's assertion that alternatives are not reevaluated before a choice. Participants viewed information about horses in a simulated race and rated each one's chance of winning three times before placing their bet and once after placing it. It was found that ratings of the chosen horse increased within the predecision period as well as after betting. Predecision bolstering occurred even when participants did not expect to bet, and predecision preference increased with task importance and participant expertise. The findings are attribute...