Regression analysis is a statistical method used to examine the relationship between variables, often employed to predict outcomes or understand associations in equine studies. In the context of horses, regression analysis can be applied to a variety of research areas, including performance metrics, health parameters, and genetic traits. By analyzing data, researchers can identify patterns or correlations that may inform breeding decisions, training regimens, or health interventions. This page compiles peer-reviewed research studies and scholarly articles that explore the application of regression analysis in equine research, focusing on methodologies, findings, and implications for horse management and care.
Ferris DJ, Frisbie DD, McIlwraith CW, Kawcak CE.Medications are frequently employed to treat intra-articular (IA) problems in the performance horse. Actual usage of the different IA medications in horses is not available. Objective: To determine the most common usage of these medications, members of the American Association of Equine Practitioners (AAEP) were surveyed. Methods: An email link to an online survey was electronically sent to 6305 AAEP members and the responses tabulated and analysed with a logistic regression model. Results: A total of 831 survey responses were submitted and tabulated. Eighty per cent of the respondents indicat...
Nagy A, Dyson S.Detailed magnetic resonance imaging (MRI) and histological appearances of the proximal aspect of the suspensory ligament (PSL) in the forelimb of nonlame horses have not been previously documented. Objective: 1) to describe detailed anatomy of the PSL, 2) describe high- and low-field MRI and histological appearances of the PSL and surrounding structures in the forelimb of horses with no carpal or proximal metacarpal pain, 3) assess the relationship between age, breed, gender, height, bodyweight and MRI findings and 4) describe the histological appearance of the PSL and compare this with MRI fi...
Butudom P, Foreman JH, Kline KH, Whittem EL.Some methods of lactate (LA) measurement have not been validated appropriately for use in horses. Objective: To validate 2 LA analysers (YSI 2300 Stat Plus and TDx Lactic Acid Assay) for use with equine plasma and to compare plasma [LA] determined by the 2 methods. Methods: Both instruments were evaluated for linearity, parallelism, recovery and precision using serial dilutions of standard LA solutions and equine plasma and then comparing results with linear regression or paired t tests. Plasma [LA] results were compared in 275 blood samples collected from horses exercising at various intensit...
Thomsen MH, Persson AB, Jensen AT, Sørensen H, Andersen PH.Equine lameness examination is based on subjective visual scoring of lameness. Instrumented objective methods for lameness examinations may be complicated to perform and the equipment is often stationary. Accelerometry has a potential clinical use; however, the reduction and interpretation of equine accelerometric data are not yet routine and the value of accelerometry in equine lameness examination is unclear. Objective: To use accelerometric data to calculate 2 different accelerometric symmetry scores and to evaluate the agreement of these with traditional lameness scores done by experienced...
Weishaupt MA, Hogg HP, Auer JA, Wiestner T.Gait analysis parameters are sensitive to alterations in velocity. For comparison of nonspeed-matched data, the velocity dependency needs to be known. Objective: To describe the changes in gait pattern and determine the relationships between stride duration, vertical impulse, contact time and peak vertical force within a range of walking and trotting speeds. Methods: Thirty-eight nonlame Warmblood horses were subjected to an incremental speed test. The spans of speed were adjusted individually to each horse and ranged from 1.1-2.1 m/s at walk and from 2.5-5.8 m/s at trot. Time, force and spati...
Dahlberg JA, Valdes-Martinez A, Boston RC, Parente EJ.Loss of arytenoid abduction is a common post operative complication of laryngoplasty without a definitive cause. It has been a clinical impression during laryngoplasty surgery that there is great conformational variability along the caudal edge of the Thoroughbred cricoid cartilage that could impact post operative retention of suture position. A change in suture position would probably lead to some loss of abduction. Defining any structural variability of the cricoid would be an initial step in determining whether this variability could impact on the retention of suture position. Objective: An...
Dziezyc J, Taylor L, Boggess MM, Scott HM.To determine the effect of ocular blinkers on driving horses' reactions to visual and audible stimuli. Methods: Balanced crossover trial with horses randomly assigned to either wear blinkers or not wear blinkers first or second, then subjected to repeated sequences of four distinct stimuli (chain rattle, cap gun, umbrella opening, and shaking of an aluminum can containing coins). Two weeks later, this process was repeated with the ordering of wearing blinkers reversed. Methods: Eight driving horses of various breeds. Methods: Responses were recorded quantitatively as inter-beat times (the time...
Senior JM, Proudman CJ, Leuwer M, Carter SD.Endotoxaemia is frequently presumed on the basis of clinical signs in horses with colic. Objective: Measurements of plasma endotoxin (LPS) are rarely made in clinical cases and there is little information on the correlations between this variable, clinical variables and outcomes. Objective: To measure LPS levels in plasma of horses presented to the Philip Leverhulme Equine Hospital on admission and daily for up to 4 days and to relate LPS levels to selected clinical parameters, such as heart rate and packed cell volume, and outcomes. Methods: Blood samples were collected and stored at -20°C p...
Durando MM, Birks EK, Hussey SB, Lunn DP.Myocarditis is thought to occur secondary to equine influenza virus (EIV) infections in horses, but there is a lack of published evidence. Objective: We proposed that EIV challenge infection in ponies would cause myocardial damage, detectable by increases in plasma cardiac troponin I (cTnI) concentrations. Methods: Twenty-nine influenza-naïve yearling ponies: 23 were part of an influenza vaccine study (11 unvaccinated and 12 vaccinated), and were challenged with 10⁸ EID₅₀ EIV A/eq/Kentucky/91 6 months after vaccination. Six age-matched healthy and unvaccinated ponies concurrently housed...
Jenner F, Kirker-Head C.To determine the effect of core decompression surgery and bone mineral density (BMD) on the mechanical properties of equine navicular bones. Methods: Experimental, in vitro study. Methods: Fore limb navicular bones (n=36 pairs) from sound 2-5-year-old horses with no radiographic abnormalities of the distal aspect of the forelimbs. Methods: Navicular BMD was measured using dual energy X-ray absorptiometry. One randomly assigned navicular bone from each pair served as control. The contralateral test specimen was allocated to 1 of 6 treatment groups defined by drill bit size (3.2 versus 2.5 mm di...
Alberghina D, Giannetto C, Piccione G.The purpose of this study was to evaluate the influence of exercise on plasma tryptophan (TRP) and free serotonin (f5-HT), whole blood-5-HT (WB-5-HT) and f5-HT/WB-5-HT ratio in Italian Saddle horses. Six clinically healthy Italian Saddle horses were subjected to a 450 meters obstacles course. Blood samples were collected from each horse by jugular venipuncture using vacutainer tubes with K(3)-EDTA at rest, immediately after exercise, and after 30 min. TRP, f5-HT and WB-5-HT were analyzed by HPLC. Immediately after exercise, statistically significant increases of f5-HT (p <0.001) and WB-5-HT (p...
Nolen-Walston RD, Norton JL, Navas de Solis C, Underwood C, Boston R, Slack J, Dallap BL.Central venous pressure (CVP) is used in many species to monitor right-sided intravascular volume status, especially in critical care medicine. Objective: That hypohydration in adult horses is associated with a proportional reduction in CVP. Methods: Ten healthy adult horses from the university teaching herd. Methods: In this experimental study, horses underwent central venous catheter placement and CVP readings were obtained by water manometry. The horses were then deprived of water and administered furosemide (1 mg/kg IV q6h) for up to 36 hours. Weight, CVP, vital signs, PCV, total protein (...
Franz R, Soliva CR, Kreuzer M, Hummel J, Clauss M.It is assumed that small herbivores produce negligible amounts of methane, but it is unclear whether this is a physiological peculiarity or simply a scaling effect. A respiratory chamber experiment was conducted with six rabbits (Oryctolagus cuniculus, 1.57±0.31 kg body mass) and six guinea pigs (Cavia porcellus, 0.79±0.07 kg) offered grass hay ad libitum. Daily dry matter (DM) intake and DM digestibility were 50±6 g kg⁻⁰·⁷⁵ d⁻¹ and 55±6% in rabbits and 59±11 g kg⁻⁰·⁷⁵ d⁻¹ and 61±3% in guinea pigs, respectively. Methane production was similar for both species (0.2...
Simhofer H, Niederl M, Anen C, Rijkenhuizen A, Peham C.The objective of this study was to compare masticatory movements before and after dental treatment using kinematic analysis. The masticatory movements of 15 adult Warmblood horses with mild dental pathology chewing standardised hay were recorded on three consecutive days before and three times after (days 7, 21, 28) dental correction. The results of the leading mandibular tracking marker, located at the caudal edge of the inter-mandibular suture, were compared statistically. Reproducibility of measurements prior to dental treatment was excellent (P<0.05). Rostrocaudal mandibular motion was ...
Christen-Clottu O, Klocke P, Burger D, Straub R, Gerber V.Equine sarcoids (ES) are common, difficult to treat, and have high recurrence rates. Viscum album extracts (VAE) are used in human cancer treatment. Objective: That therapy with VAE (Iscador P) is effective in the treatment of ES. Methods: Fifty-three horses (444 ES); 42 were treated with VAE or placebo as monotherapy; 11 were treated with VAE or placebo after selective excision of ES. Methods: Prospective, randomised, blinded, clinical trial. Horses were randomly assigned to treatment (VAE; n=32) or control group (Placebo; n=21). One milliliter of VAE (Iscador P) in increasing concentrations ...
Peeters M, Sulon J, Beckers JF, Ledoux D, Vandenheede M.In horses, serum cortisol concentration is considered to provide an indirect measurement of stress. However, it includes both free and bound fractions. The sampling method is also invasive and often stressful. This is not the case for salivary cortisol, which is collected using a more welfare-friendly method and represents a part of the free cortisol fraction, which is the biologically active form. Objective: To compare salivary and serum cortisol assays in horses, in a wide range of concentrations, using an adrenocorticotropic hormone (ACTH) stimulation test, in order to validate salivary cor...
Clutton RE, Chase-Topping M, Squires R, Lawson H, Minard H, Rose S.The dimensions of anaesthetised hobbled horses during suspension and transfer onto the operating table are unknown. These data are required for the cost-effective construction of equine surgical facilities. Objective: To measure the distance from the toe to dependent back margin (Bsusp) and poll (Psusp) of anaesthetised suspended horses and correlate them with readily obtained measures from standing animals. Methods: Digital photographs of suspended horses were taken in the anaesthesia induction box at a fixed position that allowed trigonometric determination of Bsusp and Psusp. These values w...
Gómez MD, Menendez-Buxadera A, Valera M, Molina A.A total of 71 522 records (from 3154 horses) with the times per kilometre (TPK), recorded in Spanish Trotter horses (individual races) from racing performances held from 1991 to 2007, were available for this study. The TPK values for the different age groups (young and adult horses) and different distances (1600-2700 m) were considered as different traits, and a bi character random regression model (RRM) was applied to estimate the (co)variance components throughout the trajectory of age groups and distances. The following effects were considered as fixed: the combination of hippodrome-dat...
Chiavaccini L, Hassel DM.Esophageal obstruction is common in horses and can result in life-threatening complications. Previous studies have described clinical findings in horses with esophageal obstruction, but there are no reports that attempt to make correlations of clinical findings with outcome. Objective: Specific clinical features of horses with esophageal obstruction are associated with increased likelihood of complications. Methods: One hundred and nine horses with esophageal obstruction. Methods: Retrospective cross-sectional study. All clinical records of horses admitted between April 1992 and February 2009 ...
Curtis GC, Grove-White D, Ellis RN, Argo CM.Standard and modified measuring sticks were used to record height at the withers and a 'non-contact' laser was used to measure withers and loin heights. Sixty horses and ponies, ranging in height (115 to 155 cm) and body condition score (BCS) (moderate to obese) were measured by each method at 10-minute intervals for 40 minutes. Measurement series were repeated over three successive days. Unique regression models were constructed for method-specific data. Coefficients of variation were similar for stick and laser methods (0.002 to 0.004 per cent). Models were not influenced by day of measureme...
Posta J, Malovhr S, Mihók S, Komlósi I.The aim of this study was to estimate the genetic parameters for show-jumping competition performance of Hungarian Sporthorses using a random regression model. There were 21,210 records from 739 horses collected in Hungary between 1996 and 2004. Performance was expressed as shifted Blom normalized ranks and as the difference between fence height and fault points. The random regression model (RRM) included fixed effects for sex, year, location, and obstacle height and random effects for animal, rider and permanent environment. Regressions for the random effects in the RRM were modelled with Leg...
van Heel MC, van Dierendonck MC, Kroekenstoel AM, Back W.Foot stance in grazing significantly influences hoof conformation and development from foal to yearling age. Objective: To conduct a longitudinal study to establish if the relationship between motor laterality and uneven front feet persisted in 3-year-old horses at the time of studbook selection and to investigate if such laterality and unevenness might influence the horses' ability to perform symmetrically while trotting, cantering and free jumping. Methods: Seventeen clinically sound but untrained (with only minimal experience of handling) and sound Warmblood horses that had participated in ...
Kamm JL, Bramlage LR, Schnabel LV, Ruggles AJ, Embertson RM, Hopper SA.Analysis was performed to examine a method for refining the preoperative prognosis for horses that had surgery to remove apical fractures of the proximal sesamoid bones (PSBs). Objective: To determine if: 1) there was a difference in size or configuration of apical fractures between the different anatomical locations of the PSBs, which have been shown to affect the prognosis; and 2) the size or configuration could predict the prognosis for racehorses with these fractures. Methods: The study included 110 weanlings and yearlings and 56 training racehorses that underwent surgery to remove apical ...
Loesch A, Mayhew TM, Tang H, Ladd FV, Ladd AA, de Melo MP, da Silva AA, Coppi AA.The superior cervical ganglion (SCG) in mammals varies in structure according to developmental age, body size, gender, lateral asymmetry, the size and nuclear content of neurons and the complexity and synaptic coverage of their dendritic trees. In small and medium-sized mammals, neuron number and size increase from birth to adulthood and, in phylogenetic studies, vary with body size. However, recent studies on larger animals suggest that body weight does not, in general, accurately predict neuron number. We have applied design-based stereological tools at the light-microscopic level to assess ...
Cheetham J, Riordan AS, Mohammed HO, McIlwraith CW, Fortier LA.There is no consensus on objective outcome measures that can be used to determine if a medical or surgical treatment affects race performance. Objective: To determine the association between 2 commonly used outcome measures (total starts and total earnings) and age, sex, gait and race surface. Methods: A cross-sectional study was performed using the race performance data for all Thoroughbred horses age 2, 3, 4 and 5 years racing in the United States, and Standardbred horses of the same ages racing in the United States and Canada during the year 2006. Median earnings and starts were determined ...
Kaps M, Curik I, Baban M.Heterogeneity of variance of growth traits over age is a common issue in estimating genetic parameters and is addressed in this study by selecting appropriate variance structure models for additive genetic and environmental variances. Modeling and partitioning those variances connected with analyzing small data sets were demonstrated on Lipizzan horses. The following traits were analyzed: withers height, chest girth, and cannon bone circumference. The measurements were taken at birth, and at approximately 6, 12, 24, and 36 mo of age of 660 Lipizzan horses born in Croatia between 1948 and 2000....
Vecchi I, Sabbioni A, Bigliardi E, Morini G, Ferrari L, Di Ciommo F, Superchi P, Parmigiani E.Standardbred maiden mares are generally stressed and in poor physical condition because of their incorrect management at the end of their racing careers. The purpose of this study was to identify an objective assessment that, similar to body condition score (BCS) determination, is easy to measure and able to confirm or improve fattening status assessment, as well as to ascertain whether a relationship with reproduction efficiency exists in subjects destined for a first-time insemination program. The authors assessed 29 Standardbred maiden mares (7 +/- 2 years old) during the breeding season. O...
Barakzai SZ, Boden LA, Dixon PM.To (1) assess the degree of arytenoid cartilage abduction lost after laryngoplasty (LP) in Thoroughbred National Hunt racehorses and (2) to correlate postoperative racing performance with degree of arytenoid abduction after LP. Methods: Case series. Methods: National Hunt Thoroughbred racehorses (n=68). Methods: Grade of postoperative arytenoid abduction for National Hunt racehorses that had LP with ventriculocordectomy was assessed at 1 day, 6 days, and 6 weeks after LP. Race records were analyzed to ascertain if there was correlation between the degree of arytenoid cartilage abduction and va...
Tabar-Rodriguez JJ, Cruz AM, Monteith G, Gordon K, Hurtig MB.OBJECTIVE-To use quantitative ultrasonography to evaluate the association between the speed of sound (SOS) at 9 sites in the third metacarpal bone (MCIII) of racing Thoroughbreds with workload accumulation and the effect that MCIII failure has on this association. ANIMALS-Sixty-two 2- and 3-year-old Thoroughbreds in racing condition. PROCEDURES-Cumulative work index (CWI) was used to calculate total workload (CWI(total)) and also 3 independent CWIs for the various gaits (ie, trot [CWI(trot)], gallop [CWI(gallop)], and race [CWI(race)]) used during training and racing. Speed of sound was monito...
Rustin M, Janssens S, Buys N, Gengler N.Genetic parameters for the height at withers, 27 linear type and six linear gait traits were estimated for the Belgian warmblood horse. Observations on 987 mares, mostly 3 years old, were analysed using a multi-trait animal model. The statistical model included appraiser, age and location (date x place of appraisal) as fixed effects. Genetic parameters were estimated using a canonical transformation and an expectation-maximization restricted maximum likelihood algorithm with an additional deceleration step. Estimates of heritability for the 33 linear traits were between 0.15 and 0.55. Heritabi...
Furr MO, Bender H.To determine the effects of age on each analyte, CSF variables were evaluated in healthy foals from birth through 42 days of age. Cerebrospinal fluid was collected from 14 clinically normal, naturally delivered cross-bred foals and was analyzed for glucose, sodium, potassium, magnesium, and total protein concentrations, total and differential WBC counts, RBC count, and lactate dehydrogenase, aspartate transaminase, and creatine kinase activities. Samples were collected in 3 foals < 48 hours old, and at 11 to 14 days of age in 4 foals, 21 to 22 days of age in 3 foals, and 31 to 42 days of ag...
Brown JA, Derksen FJ, Stick JA, Hartmann WM, Robinson NE.Laryngoplasty is the technique of choice for treatment of laryngeal hemiplegia, with the aim of improving airway function and/or eliminating respiratory noise. However, there are no quantitative data in the literature describing the effect of laryngoplasty on upper airway noise or its relationship to upper airway mechanics in horses with laryngeal hemiplegia. Objective: To determine whether laryngoplasty reduces respiratory noise in exercising horses with laryngeal hemiplegia; and to establish whether the degree of upper airway obstruction can be predicted by upper airway noise, or the degree ...
Jansen MO, van Buiten A, van den Bogert AJ, Schamhardt HC.The in vivo strains of the musculus interosseus medius (suspensory ligament) and its rami extensorii (extensor branches) in the forelimb of the horse were determined from angular changes of the metacarpophalangeal and the distal interphalangeal joints. For this purpose, regression models were fitted to strains and joint angle combinations measured in in vitro limb loading experiments. The in vivo strains were computed from the kinematics of 8 horses at the walk, the trot and the canter. It was found that the extensor branches were strained about 1.0% at hoof impact, which indicates that they p...
Lapsina S, Riond B, Hofmann-Lehmann R, Stirn M.Bronchoalveolar lavage (BAL) is a diagnostic method for the assessment of the lower respiratory airway health status in horses. Differential cell count and sometimes also total nucleated cell count (TNCC) are routinely measured by time-consuming manual methods, while faster automated methods exist. The aims of this study were to compare: 1) the Sysmex XN-V body fluid (BF) mode with the manual techniques for TNCC and two-part differential into mononuclear and polymorphonuclear cells; 2) the Olympus VS200 slide scanner and software generated deep-learning-based algorithm with manual techniques f...
Mouncey R, Arango-Sabogal JC, de Mestre AM, Verheyen KL.Flexural and angular limb deformities (LD) are an important cause of early-life morbidity and mortality/euthanasia in Thoroughbred foals. The majority are congenital in origin but, to date, their precise aetiology is poorly understood. We hypothesised that maternal- and pregnancy-level factors, particularly those with potential to influence in-utero growth and development, could play an important role. The aim of this study was therefore to investigate associations between such factors and early-life LD in Thoroughbred foals. A birth cohort was established on seven farms across the United King...
Mohammed HO, Cummings JF, Divers TJ, de la Rua-Domenech R, de Lahunter A.Equine motor neuron disease (EMND) is a newly recognized neurodegenerative disorder of bulbospinal motor neurons in the horse. We conducted a case-control study to identify intrinsic factors associated with the risk of this disorder. Seventy-four cases and 160 controls were assembled. Controls included horses diagnosed with equine protozoal myelitis, equine degenerative myeloencephalopathy, and cervical stenotic myelopathy during the same time period as the cases. Logistic regression analysis was used to evaluate the association of each hypothesized factor while simultaneously controlling for ...
Assal AN, Poulsen JS.The changes in pH, pCO2, pO2, BE, SBC, and lactic during storage of equine venous and arterial blood in 24 hours at different temperatures were measured (tables I, II), and illustrated (fig, 1, 2, 3). Correction tables (tables VI, VII) for determination of the initial acid-base data are constructed based on regression equations (tables IV, V) of the in vitro changes of the blood. The changes in the acid-base values of equine blood differ from that of bovine and canine blood (table III).
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 ...
Cymbaluk NF, Schryver HF, Hintz HF.The effects of copper intake on stable copper and 64Cu metabolism and on the excretory pathways of absorbed copper were examined in ponies. Bile and feces collected from two bile duct-cannulated ponies following an intravenous dose of 64Cu showed that bile was the main route of endogenous copper excretion. Stable copper and 64Cu metabolism were examined in three intact ponies fed dietary copper to provide 5.6, 16.6 and 25.7 mg Cu/100 kg body weight/day. The amount of copper excreted in urine was not influenced by dietary treatment. Stable copper absorption and 64Cu retention significantly incr...
Bennet ED, Cameron-Whytock H, Parkin TDH.The equestrian discipline of eventing tests athletes' and horses' skill over three phases: dressage, jumping and cross-country. Falls during cross-country can be particularly serious and result in serious or fatal injury for both horse and athlete. Cross-country course and fence design are crucial contributory factors to safety. Objective: To provide descriptive statistics and identify fence-level risk factors for horses competing in Fédération Equestre Internationale (FEI) events worldwide. Methods: Retrospective cohort study. Methods: Data were collected for every horse start worldwide in ...
Magdesian KG, Brook D, Wickler SJ.The temporal response of blood and serum proteins to chronic plasmapheresis was determined in 8 horses used in a commercial antibody enterprise. Plasmapheresis of between 4 and 11 L induced significant decreases in total protein, albumin, and IgG values. With the exception of a high hematocrit value for the first postplasmapheresis blood sample, there were no changes in erythrocyte or leukocyte measurements, and no changes in the proportions of serum protein in an electrophoretic profile. Regression equations generated for recovery of proteins after plasmapheresis indicated a return to preplas...
Albertsdóttir E, Arnason T, Eriksson S, Sigurdsson A, Fikse WF.The genetic evaluation of Icelandic horses is currently based on results from breeding field tests of riding ability and conformation. The effect of integrating competition traits and/or test status into the genetic evaluation was studied concerning estimation bias, predictive ability, accuracy, correlations between breeding values and ranking of sires. Breeding field test data included 19 954 records from horses assessed in 11 countries during 1994-2008. Competition data included 44 160 records from 7687 horses competing in Iceland and Sweden in 1998-2008. Test status was defined as attendanc...
Pre-clinical studies on human isolated bronchi have relevant translational value in human in vivo, conversely no investigation has been performed to assess whether data resulting from equine isolated airways can have any translational application in asthmatic horses. Thus, a meta-regression analysis via random-effect method was carried out to correlate the pharmacological characteristics of bronchodilators resulting from experiments performed in equine isolated bronchi with their impact on the lung function outcomes in asthmatic horses. Data on the potency of different bronchodilators were ext...
Klingberg J, Cawley A, Shimmon R, Fu S.The constant evolution of the illicit drug market makes the identification of unknown compounds problematic. Obtaining certified reference materials for a broad array of new analogues can be difficult and cost prohibitive. Machine learning provides a promising avenue to putatively identify a compound before confirmation against a standard. In this study, machine learning approaches were used to develop class prediction and retention time prediction models. The developed class prediction model used a naïve Bayes architecture to classify opioids as belonging to either the fentanyl analogues, AH...
Augustinsson KB, Bartfai T, Mannervik B.The steady-state kinetics of the butyrylcholinesterase-catalysed hydrolysis of butyrylthiocholine and thiophenyl acetate were shown to deviate from Michaelis-Menten kinetics. The ;best' empirical rate law was selected by fitting different rate equations to the experimental data by non-linear regression methods. The results were analysed in view of two alternative interpretations: (1) the reaction is catalysed by a mixture of enzymes, or (2) the activity is due to a single enzyme displaying deviations from Michaelis-Menten kinetics. It was concluded that the second alternative applies, and this...
Wilson BJ, Thompson KR, McGreevy PD.The annual Melbourne Cup Thoroughbred horse race has iconic status among many Australians but sits in the context of increasing criticism of the welfare of Thoroughbred racing horses and the ethics of gambling. Despite heated debates and protests playing out in the public domain, there is scant empirical research to document Australian attitudes to the Melbourne Cup, or horse racing more generally. Specifically, little is known about how support for or against the Melbourne Cup correlate with age, gender, income and level of education. To provide a more nuanced understanding of attitudes towar...
Lores M, Stryhn H, McD￮ L, Rose P, Muirhead T.To develop a transcutaneous ultrasonography (TUS) method for measuring the location of the stomach during various levels of fluid distension and evaluate any correlation between gastric fluid distension and stomach position. Methods: 6 adult horses. Methods: Known volumes of water were administered in 2 trials. In trial 1, the stomach was evaluated prior to and after the administration of 2, 4, and 6 L of water. In trial 2, the stomach was evaluated after administration of 6, 8, 10, and 12 L of water. The TUS was performed at the 7th through 16th left intercostal spaces (ICSs). For each volume...
Gmel AI, Haraldsdóttir EH, Bragança FMS, Cruz AM, Neuditschko M, Weishaupt MA.In gait quality assessments of horses, stride length (SL) is visually associated with spectacular movements of the front limbs, and described as ground coverage, while the movement of the hind limb under the body is supposedly essential to a longer over-tracking distance (OTD). To identify movement patterns with strong associations to SL and OTD, limb and body kinematics of 24 Franches-Montagnes (FM) stallions were measured with 3D optical motion capture (OMC) on a treadmill during an incremental speed test at trot (3.3-6.5 m/s). These measurements were correlated to the scores of ground cover...
Silva DEC, Penitente-Filho JM, Souza Netto DL, Waddington B, de Oliveira RR, Guimarães JD.This study aimed to describe the testicular growth curve in Mangalarga Marchador stallions fitting nonlinear models to data of total scrotal width (TSW) and testicular volume (TV). A cross-sectional study was conducted with 120 stallions, aging from 1.75 to 21.93 years. The parameters of nonlinear models (Brody, Gompertz, Hill, Logistic I and II, Meloun I and II, Michaelis-Menten, Mitscherlich, and von-Bertalanffy) were estimated by Gauss-Newton iterative process. Goodness of fit was evaluated by the corrected Akaike (AICc) and Bayesian (BIC) information criteria, adjusted R, error sum of squa...
Valente AC, Brosnan RJ, Guedes AG.To evaluate pharmacokinetics, recovery times, and recovery quality in horses anesthetized with 1.2 times the minimum alveolar concentration of sevoflurane or desflurane. Methods: 6 healthy adult horses. Methods: Anesthesia was maintained with sevoflurane or desflurane for 2 hours at 1.2 times the minimum alveolar concentration. Horses recovered without assistance. During recovery, end-tidal gas samples were collected until horses spontaneously moved. Anesthetic concentrations were measured by use of gas chromatography. After a 1-week washout period, horses were anesthetized with the other inha...
Franzén Lindgren E, Hammarqvist F, Ahl Hulme R.Horse-riding is practiced on a regular basis by 500,000 people in Sweden. It is reputed to be one of the most dangerous sports. On average, there were 1756 acute injuries and three fatalities each year between 1997 and 2014 in Sweden related to horses. The primary aim of this study was to outline the injury spectrum related to equestrian activities cared for at a large Swedish trauma centre. The secondary aim was to identify trends in clinical outcomes and to investigate the association between age and such outcomes. Methods: The electronic medical records system at Karolinska University Hosp...
Daniels A, Pezzanite LM, Griffenhagen GM, Hendrickson DA.The frequency of surgical site infection (SSI) following orthopaedic implant placement in horses has been reported but not compared with respect to specific antibiotic protocols administered. To determine factors associated with SSI in horses undergoing proximal interphalangeal joint (PIPJ) arthrodesis including perioperative antibiotic protocols. Records were evaluated (2010-2019), and horses undergoing PIPJ arthrodesis were identified. Patient signalment, supervising surgeon, reason for surgery, limb, implants placed, anaesthetic time, duration casting/coaptation postoperatively, antibiotic ...
Hanson CM, Kline KH, Foreman JH.Heart scores (the arithmetic mean of the QRS durations of the three bipolar limb leads for 10 cycles) and heart weights were determined from five draft type horses and five racing type horses, and evaluated for relationships between heart score and heart size within and between the two different types of horses. Horses were killed using a captive bolt gun, and actual heart weights were recorded using an electronic digital scale. The linear regression equation for heart weight versus heart score had a significant (P < 0.05) negative slope for racing types. The regression coefficients for heart ...
Gómez MD, Menéndez-Buxadera A, Valera M, Molina A.The performance results of Spanish Trotter Horses were merged with the information from the nearest official weather stations, to estimate the effects of temperature (T) on speed during the day of the race. The resulting data set included: 104 125 individual results from 7653 races with 3772 participant horses and driven by 1402 jockeys. After a classical repeatability animal model in which the effects of T were assumed null, a total of five different random regression models (RRM) with the same fixed part were applied in a parsimonious nested process in which the (co)variance components for ...
Atwill ER, Mohammed HO, de la Rua-Domenech R.A total of 2,579 serum samples from horses in New York state during 1985-1986 were examined for seropositivity to Ehrlichia risticii using the indirect fluorescent antibody technique. Cluster analysis statistical technique was used to group counties according to their estimated EME-disease rate (seropositive proportion of sampled horses). Counties were clustered into 4 groups of different EME-disease rates, representing high (86% seropositive), medium (66% seropositive), medium-low (47% seropositive) and low (6% seropositive) risk regions. The logistic regression statistical technique was used...
Fubini SL, Erb HN, Freeman KP, Todhunter RJ.Between July 1, 1983 and December 31, 1990, risk factors were determined for all horses with joint disease presented to a referral center, of being discharged, of ever becoming sound, or of being alive at 3 mo follow-up. Logistic multiple-regression models were done separately for foals (< or = 4 mo), yearlings (> 4-24 mo) and racing or nonracing adult horses (> 24 mo). The breakdown in this study was 53 foals, 87 yearlings, 141 nonracing adults, and 226 racing adults. Thirty-one foals (58%), 68 yearlings (78%), 119 non-racing adults (84%), and 213 racing adults (94%) were discharged. Foals wi...
Nielsen K, Vibe-Petersen G.Heart scores increased with age and training. Yearlings had average heart scores of approximately 90 milliseconds (msecs). This increased to approximately 110 msecs in 5-year-old horses, after which there was only slight further increase. In horses 4 years or older, regression analysis revealed a highly significant correlation between heart score and kilometre time. In younger horses the level of significance was less. There was a positive correlation between heart scores and earnings in races. Thus, horses with heart scores above 115 msecs had won considerably more than horses with lower hear...
Jenner F, Kirker-Head C.To determine the effect of core decompression surgery and bone mineral density (BMD) on the mechanical properties of equine navicular bones. Methods: Experimental, in vitro study. Methods: Fore limb navicular bones (n=36 pairs) from sound 2-5-year-old horses with no radiographic abnormalities of the distal aspect of the forelimbs. Methods: Navicular BMD was measured using dual energy X-ray absorptiometry. One randomly assigned navicular bone from each pair served as control. The contralateral test specimen was allocated to 1 of 6 treatment groups defined by drill bit size (3.2 versus 2.5 mm di...
Tayari H, Flaherty D, Schauvliege S, La Rosa L, Auckburally A.To assess the accuracy and trending capability of continuous measurement of haemoglobin concentration [Hb], haemoglobin oxygen saturation (SaO) and oxygen content (CaO) measured by the Masimo Radical-7 pulse co-oximeter in horses undergoing inhalational anaesthesia. Methods: Prospective observational clinical study. Methods: A group of 23 anaesthetized adult horses. Methods: In 23 healthy adult horses undergoing elective surgical procedures, paired measurements of pulse co-oximetry-based haemoglobin concentration (SpHb), SaO (SpO), and CaO (SpOC) and simultaneous arterial blood samples were co...
Laukkanen T, Karma L, Virtala AM, Mykkänen A, Pehkonen J, Rossi H, Tuomola K, Raekallio M.Equine dental diseases are often underdiagnosed and their signs inadequately reported. Many horse owners have difficulties in recognizing pain-related behavioral signs and in associating them with dental pain. Our objective was to determine what type and degree of dental findings may cause behavioral signs associated with dental pain. In this cross-sectional study, dental examination was performed on 183 adult horses and cheek tooth findings were scored. Owners filled in an internet-based questionnaire including 35 questions concerning eating behavior, bit behavior, and general behavior of the...
