Objective Assessment of Equine Locomotor Symmetry Using an Inertial Sensor System and Artificial Intelligence: A Comparative Study.

In horses, quantitative assessment of gait parameters, as with the use of inertial measurement units (IMUs) systems, might help in the decision-making process. However, it requires financial investment, is time-consuming, and lacks accuracy if displaced. An innovative artificial intelligence marker-less motion tracking system (AI-MTS) may overcome these limitations in the field. Our aim was to compare the level of agreement and accuracy between both systems and visual clinical assessment. Twenty horses underwent locomotion analysis by visual assessment, IMUs, and AI-MTS systems, under the following conditions: straight hard (SH), straight soft (SS), left and right circle hard (LCH, RCH), and soft (LCS, RCS). A greater number of horses were considered sound by clinical examination, compared to those identified as symmetric by the two gait analysis systems. More limbs were considered asymmetric by the AI-MTS compared to IMUs, suggesting its greater sensitivity. The greatest agreement between the two systems was found for the difference between two minima in vertical head position in SH, while the lowest for the difference between two minima in vertical pelvis position in SS, reflecting the difficulties in assessing asymmetry of the hindlimbs. It is unknown what degree of asymmetry is clinically relevant, suggesting that more consistent use in training horses may help determine the thresholds for asymmetry. Some degree of asymmetry may be clinically relevant, suggesting its regular use in training horses.

Cytokine mRNA expression in the bronchoalveolar lavage cells from horses affected by different equine asthma subtypes.

Equine asthma (EA) is a respiratory syndrome associated with the increase of different leukocyte populations in the bronchoalveolar lavage fluid (BALF). Its pathogenetic mechanisms remain unclear. This study aimed to evaluate the associations between the mRNA expression of different cytokines in the BALF, different EA subtypes and lung function. Fifteen horses underwent physical examination, airway endoscopy, BALF cytology and lung function testing (8/15). One horse did not have evidence of EA and was used as healthy reference, while the others were classified as affected by neutrophilic or mixed granulocytic EA. Cells isolated from the residual BALF were used for IL-1ß, IL-2, IFN-γ, IL-4, IL-17A genes expression by quantitative RT-PCR., Cytokine expression was compared between groups, and their correlations with BALF leukocyte and lung function were evaluated. IL-1ß expression was positively correlated with BALF neutrophils count (p=0.038, r=0.56) and with increased expiratory resistance (p=0.047, r=0.76). IFN-γ was correlated with BALF mast cells (p=0.029, r=0.58). IL-4 was higher in horses with mixed granulocytic EA than neutrophilic (p=0.008), positively correlated with BALF mast cells (p=0.028, r=0.59) and inversely with whole-breath (p=0.046, r=-0.76) and expiratory reactance (p=0.003, r=-0.93). Finally, IL-17A was inversely correlated with expiratory reactance (p=0.009, r=-0.92). These results support that multiple immune responses are involved in EA pathogenesis; innate, Th2, and Th17 responses. Innate immunity appeared associated with neutrophilic inflammation, and Th2 response with increased mast cells. The role of Th1 response in EA remains questionable.

Respiratory oscillometry testing in relation to exercise in healthy and asthmatic Thoroughbreds.

BACKGROUND: Racehorses may experience exercise-induced bronchodilation or bronchoconstriction, with potential differences between healthy and asthmatic individuals. OBJECTIVES: To identify exercise-related lung function variations by oscillometry in racehorses, compare lung function between healthy and mild equine asthma (MEA) horses, assess oscillometry's potential as a predictor of racing fitness. STUDY DESIGN: Prospective case-control clinical study. METHODS: Fourteen Thoroughbred racehorses (5 healthy, 9 MEA) underwent a protocol including respiratory oscillometry at rest, exercise with fitness monitoring, oscillometry at 15 and 45 min post-exercise, and bronchoalveolar lavage fluid (BALf) cytology. Oscillometry parameters (resistance [Rrs] and reactance [Xrs]) were compared within and between healthy and MEA groups at different timepoints. Associations between Rrs and Xrs at rest and 15 min post-exercise and BALf cytology and fitness indices were evaluated. RESULTS: MEA horses showed higher Rrs at 15 min post-exercise (0.6 ± 0.2 cmH2 O/L/s) than healthy horses (0.3 ± 0.1 cmH2 O/L/s) (p < 0.01). In healthy horses, Rrs decreased at 15 min post-exercise compared with resting values (0.5 ± 0.1 cmH2 O/L/s) (p = 0.04). In MEA horses, oscillometry parameters did not vary with time. Post-exercise Xrs inversely correlated with total haemosiderin score (p < 0.01, r2 = 0.51). Resting Rrs inversely correlated with speed at 200 bpm (p = 0.03, r2 = -0.61), and Xrs with maximum heart rate (HR) during exercise (p = 0.02, r2 = -0.62). Post-exercise Rrs inversely correlated with mean (p = 0.04, r2 = -0.60) and maximum speed (p = 0.04, r2 = -0.60), and HR variability (p < 0.01, r2 = -0.74). MAIN LIMITATIONS: Small sample size, oscillometry repeatability not assessed, potential interference of upper airway obstructions, external variables influencing fitness indices. CONCLUSIONS: Oscillometry identified lung function differences between healthy and MEA horses at 15 min post-exercise. Only healthy horses exhibited exercise-induced bronchodilation. Oscillometry showed potential in predicting subclinical airway obstruction.

Evaluation of fitness parameters in relation to racing results in 245 Standardbred trotter horses submitted for poor performance examination: A retrospective study.

In racehorses, the associations between physiological parameters obtained by exercise testing and racing results have been questioned. We hypothesized that fitness variables measured during a treadmill incremental test may be related with racing outcomes and lifetime career. Our study aimed to investigate the role of fitness parameters obtained during a treadmill test in performance evaluation and career prediction in poorly performing Standardbreds, through a retrospective review of the clinical records of 245 trotters that underwent an incremental treadmill test. Several fitness parameters were assessed, and their correlations with racing data (number of starts, wins and placings) in the 3 months before and 6 months after examination were evaluated; moreover their associations and predictive power for lifetime racing results and earnings were considered. The associations between fitness parameters and measures of racing performance as well as the associations between racing results over time were evaluated by Spearman's correlation in the whole population and in different age groups. Multivariate regression models predicting the total number of starts, wins and earnings based on fitness parameters were constructed, controlling for age, weight, and sex. Maximum speed and the speed at the aerobic threshold were the parameters correlated with the most racing results, in the three evaluation periods (3 months before, 6 months after, lifetime). Other parameters predictive of career outcomes were maximum blood lactate concentration and maximum hematocrit. Interestingly, in 2-year-old Standardbreds, the only parameters correlated with racing results were maximum hematocrit and minimum pH, suggesting they may reflect individual potential. Both the racing results obtained before and after examination were predictive of lifetime career, with those following hospitalization being more strongly correlated. In conclusion, parameters obtained during treadmill tests both reflect the racing outcomes and the career potential.

Equine Respiratory Medicine and Cardiology.

In the last few years, the attention regarding the health of the lungs and heart of equine patients has been continuously growing [...].

Associations between Medical Disorders and Racing Outcomes in Poorly Performing Standardbred Trotter Racehorses: A Retrospective Study.

Poor performance in racehorses is commonly associated with subclinical diseases. This study aims to evaluate the associations between medical disorders and racing results in Standardbred trotters. The clinical records of 248 poorly performing Standardbreds were retrospectively reviewed, and their racing results were extracted from an online database, concerning the periods 3 months before and 6 months after hospitalization and the entire lifetime. Generalized linear models were used to evaluate the effects of different disorders on racing outcomes. Airway neutrophilia was associated with limiting lifetime starts and wins pre- and post-hospitalization, while mastocytosis was associated with less wins in the post-hospitalization period. Therefore, lower airway inflammation showed both short- and long-term impacts on racing performance. Severe upper airway obstructions and gastric ulcers showed associations with less placings in the post-discharge period but no long-term influence on performance. The significance of exertional rhabdomyolysis was indeterminable, yet interference with the number of starts in the post-discharge period was reported and associated with lower total career earnings. Exercise-induced pulmonary hemorrhage and cardiac arrhythmias were not associated with worse racing outcomes: therefore, their role in poor performance remains unclear.

Medical causes of poor performance and their associations with fitness in Standardbred racehorses.

BACKGROUND: Poor performance is a multifactorial syndrome of racehorses, commonly associated with subclinical disorders, which can be diagnosed by exercise testing. OBJECTIVES: Describe the prevalence of medical causes of poor performance in Standardbreds unassociated with lameness, and evaluate their relationships with fitness variables measured by exercise treadmill test. ANIMALS: Hospital population of 259 nonlame Standardbred trotters referred for poor performance. METHODS: The horses' medical records were retrospectively reviewed. Horses underwent a diagnostic protocol including resting examination, plasma lactate concentration, treadmill test with continuous ECG and assessment of fitness variables, creatine kinase activity, treadmill endoscopy, postexercise tracheobronchoscopy, bronchoalveolar lavage (BAL), and gastroscopy. The prevalence of different disorders was evaluated, including cardiac arrhythmias, exertional myopathies, dynamic upper airway obstructions (DUAOs), exercise-induced pulmonary hemorrhage (EIPH), moderate equine asthma (MEA), and gastric ulcers (EGUS). The associations of these disorders with fitness variables were investigated individually and using multivariable models. RESULTS: Moderate equine asthma and EGUS were the most common disorders, followed by EIPH, DUAOs, cardiac arrhythmias, and exertional myopathies. Hemosiderin score was positively correlated with BAL neutrophils, eosinophils, and mast cells; increased creatine kinase activity was associated with BAL neutrophilia, DUAOs, premature complexes, and squamous gastric disease. Treadmill velocity at a plasma lactate concentration of 4 mmol/L and at heart rate of 200 beats per minute was negatively affected by BAL neutrophilia, multiple DUAOs, exertional myopathies, and squamous gastric disease. CONCLUSIONS: The multifactorial nature of poor performance was confirmed, with MEA, DUAOs, myopathies and EGUS representing the main diseases involved in fitness impairment.

Equine Gastric Ulcer Syndrome affects fitness parameters in poorly performing Standardbred racehorses.

Introduction: Equine Gastric Ulcer Syndrome (EGUS) is a highly prevalent disorder in horses, which can be classified, based on the localization of the lesions, as Equine Squamous Gastric Disease (ESGD) or Equine Glandular Gastric Disease (EGGD). Although EGUS is recognized as a common cause of poor performance in racehorses, objective investigations about its relation with athletic capacity are lacking. Therefore, the present retrospective study aims to evaluate the associations between EGUS severity and some fitness parameters measured during an incremental treadmill test in Standardbred racehorses in training. Methods: With this aim, data from 87 Standard bred racehorses which underwent a complete diagnostic evaluation for poor performance was reviewed. During gastroscopic examination, a 0-4 score was assigned to ESGD, while EGGD was evaluated for absence/presence; a total EGUS score was obtained by adding 1 point to ESGD score in horses showing concomitant EGGD. Fitness parameters obtained during incremental treadmill test included speed at a heart rate of 200 bpm (V200), speed and heart rate at a blood lactate of 4 mmol/L (VLa4, HRLa4), peak lactate, lactate and heart rate at 30 minutes post-exercise, maximum speed, minimum pH and maximum hematocrit. The associations between fitness parameters and EGUS and ESGD scores were evaluated by Spearman correlation, while Mann-Whitney test was used to compare them between horses with or without EGGD. Statistical significance was set at p<0.05. Results: EGUS grade was inversely correlated with V200 (p = 0.0025) and minimum pH (p = 0.0469); ESGD grade was inversely correlated with V200 (p = 0.0025) and VLa4 (p = 0.0363). Although a trend was observed, no significant differences in V200 were observed between horses with or without EGGD (p = 0.073); horses with EGGD reached a lower minimum pH (p = 0.0087). Discussion: These results show a negative association between aerobic capacity and EGUS, in particular ESGD. Although different hypotheses have been proposed, including abdominal pain and decreased appetite due to lactate accumulation, the underlying mechanisms are still unknown, and it is not clear whether EGUS represents a cause or a consequence of an early lactate accumulation and post-exercise acidosis.

Impact of Lower Airway Inflammation on Fitness Parameters in Standardbred Racehorses.

Mild-moderate equine asthma (MEA) is a common respiratory disorder among racehorses, characterized by lower airway inflammation. Although it is generally agreed that MEA causes poor performance, contrasting results have been reported about the effects of tracheal mucus and the leukocyte populations of the bronchoalveolar lavage (BAL) on performance. This study aims to investigate the associations between airway inflammation and fitness parameters measured during an incremental treadmill test on Standardbred racehorses. For this purpose, the clinical records of 116 Standardbreds subjected to a diagnostic protocol for poor performance were retrospectively reviewed. Parametric and nonparametric statistics were used to evaluate the relationships between endoscopic scores, BAL cytological results, and fitness parameters. Moreover, horses were divided into MEA and non-MEA groups and into neutrophilic, eosinophilic-mastocytic, and mixed MEA groups; fitness parameters were compared between groups. Neutrophils percentages were inversely correlated with the speed at a heart rate of 200 bpm, the speed and heart rate at a plasma lactate concentration of 4 mmol/L (VLa4 and HRLa4), and the maximal speed, while they were positively correlated with higher lactate concentrations. Moreover, significant differences were detected between different MEA subtypes concerning VLa4, HRLa4, and lactate concentrations. These results suggest that airway neutrophilic inflammation impairs athletic capacity in Standardbreds.

Effect of the Administration of a Nutraceutical Supplement in Racehorses with Lower Airway Inflammation.

Mild−moderate equine asthma (MEA) is a chronic inflammatory disorder of the lower airways of the horse, characterized by tracheal mucus accumulation, cough and poor performance. The therapeutic approach is based on pharmacological treatment and environmental management. Moreover, the efficacy of the administration of antioxidant molecules has been reported. The aim of the present study was to evaluate the effect of the administration of a commercial nutraceutical supplement, composed of several herbal extracts, on lower airway inflammation in racehorses. Twelve Thoroughbreds affected by MEA were selected. All horses underwent a clinical examination with assignment of a clinical score, airway endoscopy and cytological examination of bronchoalveolar lavage fluid. In seven horses, the supplement was administered for 21 days in association with environmental changes, while in five horses only environmental changes were performed. All procedures were repeated at the end of the study. Data concerning the clinical score, the endoscopic scores and the cytology at the beginning and at the end of the study were statistically compared. Data showed a significant reduction (p < 0.0156) of the clinical score and a significant reduction (p < 0.0156) of the tracheal mucus score. The results showed the beneficial effect of the supplement on mild−moderate lower airway inflammation, probably due to its antioxidant activity.

Association between dynamic upper airway obstructions and fitness parameters in Standardbred racehorses during high-speed treadmill exercise.

OBJECTIVE: To evaluate the association between the severity of dynamic upper airway obstruction (DUAO) and selected fitness parameters in Standardbred racehorses measured by treadmill test. ANIMALS: 191 Standardbred racehorses that underwent a standardized diagnostic protocol for poor performance evaluation between 2002 and 2021 at the Veterinary Teaching Hospital, University of Milan. PROCEDURES: Horses underwent a diagnostic protocol including clinical examination, lameness evaluation, laboratory analyses, ECG, resting upper airway endoscopy, metabolic incremental treadmill test, high-speed treadmill endoscopy, postexercise tracheobronchoscopy, and bronchoalveolar lavage fluid cytology. On the basis of findings of the high-speed treadmill endoscopy, horses were divided into the following groups: no DUAO, mild DUAO (medial deviation of the aryepiglottic folds or epiglottic entrapment), severe DUAO (dorsal displacement of the soft palate, nasopharyngeal collapse, dynamic laryngeal collapse, or epiglottic retroversion), and multiple DUAOs (different forms of DUAO occurring concomitantly). Fitness parameters, measured by incremental treadmill test, included speed at a heart rate of 200 bpm (V200), speed and heart rate at a lactate concentration of 4 mmol/L (VLa4, HRLa4), peak lactate, maximum speed, maximum hematocrit, and minimum pH. Data were compared between groups by use of descriptive and statistical analyses. RESULTS: Horses affected by severe or multiple DUAOs showed lower V200 and VLa4, compared to the no-DUAO group; horses with multiple DUAOs also had higher peak lactate concentrations compared to horses without DUAOs. CLINICAL RELEVANCE: While mild forms of DUAO do not affect athletic capacity, severe forms of DUAO and multiple DUAOs may lead to reduced fitness in Standardbred racehorses by impairing aerobic capacity.

Upper and Lower Airways Evaluation and Its Relationship with Dynamic Upper Airway Obstruction in Racehorses.

Dynamic upper airway obstructions (DUAO) are common in racehorses, but their pathogenetic mechanisms have not been completely clarified yet. Multiple studies suggest that alterations of the pharyngo-laryngeal region visible at resting endoscopy may be predictive of the onset of DUAO, and the development of DUAO may be associated with pharyngeal lymphoid hyperplasia (PLH), lower airway inflammation (LAI) and exercise-induced pulmonary hemorrhage (EIPH). The present study aims to investigate the possible relationship between the findings of a complete resting evaluation of the upper and lower airways and DUAO. In this retrospective study, 360 racehorses (Standardbreds and Thoroughbreds) referred for poor performance or abnormal respiratory noises were enrolled and underwent a diagnostic protocol including resting and high-speed treadmill endoscopy, cytological examination of the bronchoalveolar lavage fluid and radiographic assessment of the epiglottis length. In this population, epiglottis flaccidity was associated with dorsal displacement of the soft palate, while no relationship was detected between DUAO and epiglottis length. No associations were detected between DUAO and PLH, LAI or EIPH. In conclusion, it is likely that epiglottis plays a role in upper airway stability, while airways inflammation does not seem to be involved in the pathogenesis of DUAO.

Feasibility of Echocardiographic Estimation of Pulmonary Artery Stiffness in Horses.

Pulmonary artery stiffness (PAS) is an index of pulmonary artery elasticity that permits to evaluate the pulmonary vascular bed in humans. It can early detect an increase in pulmonary artery stiffness as a consequence of remodeling of the vessel wall caused by chronic pulmonary and congenital heart diseases. This remodeling can occur also in horses with chronic respiratory diseases. Thus, PAS could be a useful echocardiographic parameter also in horses. However, in literature, there are no studies regarding PAS in horses. The aim of this study is to evaluate the feasibility of PAS in horses. Fifteen healthy horses were included in this prospective study. Maximal frequency shift and acceleration time were measured from the pulsed-wave Doppler trace of the pulmonary artery flow, obtained from the right parasternal short-axis view at the level of the pulmonary artery, and then PAS was calculated as the ratio of Maximal frequency shift to acceleration time. The low variability assessed for intra- and inter-observer variability, day-to-day variability and image acquisition variability suggests that PAS can be measured consistently in horses. Further studies could be useful to assess the clinical usefulness of PAS in unhealthy horses, such as those affected by chronic respiratory diseases.

Associations between Exercise-Induced Pulmonary Hemorrhage (EIPH) and Fitness Parameters Measured by Incremental Treadmill Test in Standardbred Racehorses.

Exercise-induced pulmonary hemorrhage (EIPH) is a condition affecting up to 95% of racehorses, diagnosed by detecting blood in the trachea after exercise and/or the presence of hemosiderophages in the bronchoalveolar lavage fluid (BALf). Although EIPH is commonly associated with poor performance, scientific evidence is scarce. The athletic capacity of racehorses can be quantified through some parameters obtained during an incremental treadmill test; in particular, the speed at a heart rate of 200 bpm (V200), and the speed (VLa4) and the heart rate (HRLa4) at which the blood lactate concentration reaches 4 mmol/L are considered good fitness indicators. The present retrospective study aims to evaluate whether EIPH could influence fitness parameters in poorly performing Standardbreds. For this purpose, data from 81 patients regarding their V200, VLa4, HRLa4, peak lactate, maximum speed, minimum pH, and maximum hematocrit were reviewed; EIPH scores were assigned based on tracheobronchoscopy and BALf cytology. The association between the fitness parameters and EIPH was evaluated through Spearman's correlation analysis. No relationship between EIPH and V200, VLa4, and HRLa4 was observed. Interestingly, EIPH-positive horses showed higher hematocrit values (p = 0.0072, r = 0.47), suggesting the possible influence of the hemoconcentration on the increase of pulmonary capillary pressure as a part of the pathogenesis of EIPH.

A portable fan-based device for evaluating lung function in horses by the forced oscillation technique.

Objective. The assessment of lung mechanics in horses is nowadays based on invasive methods that may require sedation. The forced oscillation technique (FOT) allows the non-invasive assessment of respiratory mechanics during spontaneous breathing, but current devices are complex, cumbersome, expensive, and difficult to be applied in horses.Approach. We developed a portable FOT device based on a novel approach in which the pressure waveforms are generated by a servo-controlled ducted fan. This new approach allows the design of devices that are more sturdy, compact, and portable compared to already existing approaches. The prototype includes 1) a small microcontroller-based electronic board for controlling the fan and measuring flow and pressure and 2) an optimized data processing algorithm.Main results. This device provides a maximum error of 0.06 cmH2O·s/L and 0.15 cmH2O·s/L in measuring respiratory resistance and reactance duringin-vitrovalidation. A pilot study was also performed on three healthy horses and three horses with severe equine asthma (SEA) and it demonstrated good tolerability and feasibility of the new device. Total respiratory system resistance (Rrs) and reactance (Xrs) significantly differed (p< 0.05) between groups. At 5 Hz,Rrswas 0.66 ± 0.02 cmH2O·s/L and 0.94 ± 0.07 cmH2O·s/L in healthy and in SEA, respectively.Xrs0.38 ± 0.02 cmH2O·s/L and -0.27 ± 0.05 cmH2O·s/L.Significance. This novel approach for applying FOT allowed the development of a small, affordable, and portable device for the non-invasive evaluation of respiratory mechanics in spontaneously breathing horses, providing a useful new tool for improving veterinary respiratory medicine. Moreover, our results provide supporting evidence of the value of this novel approach for developing portable FOT devices also for applications in humans.

Innovative Blood Antioxidant Test in Standardbred Trotter Horses.

In athletic horses, prolonged and intense training gives rise to an imbalance between the production of free radicals and antioxidant molecules, leading to oxidative stress. Considering the relation between exercise and oxidative stress in horses, the present work aims to validate the Kit Radicaux Libres (KRL) test as a tool to verify the influence of taming, training and racing on the total blood antioxidant activity and some haematochemical parameters. Five Italian Standardbred racehorses (two males and three females, aged 12 ± 1 months) from the same training center were selected and monitored upon arrival and during the following year until the racing season. Blood samples were obtained at different timepoints, corresponding to different steps of training. The data showed that KRL values were higher (p < 0.001) before the beginning of the taming period and at 60 days of taming, compared with the training and racing periods; additionally, the total protein value was affected by the training program, whereas no effects of training on muscle enzymes were detected. These results confirm that exercise plays a role in the production of free radicals and show that the KRL test may represent a valid method to determine oxidative stress in athletic horses.

The Role of Thoracic Ultrasonography and Airway Endoscopy in the Diagnosis of Equine Asthma and Exercise-Induced Pulmonary Hemorrhage.

Mild-moderate (MEA), severe (SEA) equine asthma and exercise-induced pulmonary hemorrhage (EIPH) are common respiratory disorders in horses. The present retrospective study aims to evaluate the role of ultrasonography and endoscopy in the diagnosis of these conditions. Three hundred and three horses were included and divided into SEA, MEA and MEA + EIPH groups, on the basis of history, clinical examination and bronchoalveolar lavage fluid (BALf) cytology; scores were assigned to lung ultrasonography, pharyngeal lymphoid hyperplasia (PLH), tracheal mucus (TM) and tracheal bifurcation edema (TB). These scores were compared between groups, and their associations with age, BALf cytology, tracheal wash microbiology and between endoscopic and ultrasonographic scores were statistically analyzed. Ultrasonographic scores were higher in the SEA and MEA + EIPH groups and associated with increased BALf neutrophils and hemosiderophages. The PLH score was higher in younger horses affected by MEA and EIPH and associated with increased eosinophils and hemosiderophages. TM and TB scores were greater in older horses affected by SEA, associated with increased neutrophils and inversely correlated with hemosiderophages. Moreover, TM grade was negatively correlated with mast cells. Thoracic ultrasonography and airway endoscopy can provide useful information about the inflammatory status of upper and lower airways in the horse.

Effects of a nutraceutical supplement in the management of mild equine squamous gastric disease in endurance horses.

INTRODUCTION: Equine squamous gastric disease (ESGD) may require prolonged treatments with acid suppressants; therefore, interest in nutraceutical supplements with anti-ulcerogenic properties has increased. This study aims to investigate the efficacy of Trophogast pellet for the treatment of ESGD in endurance horses. MATERIAL AND METHODS: Fifteen endurance horses were included based on their gastroscopic examination and randomly assigned to a treatment group, receiving Trophogast pellet for 30 days together with management changes, or to a control group, only subjected to management modifications. At the end of treatment, gastroscopy was repeated. Scores were assigned according to the Equine Gastric Ulcer Council scoring system. All horses were weighed at the beginning and at the end of the study. ESGD grades and weight before and after treatment were compared. RESULTS: At enrolment, median ESGD score in the treatment group was 2, while in the control group it was 1. After the treatment period, a significant decrease in ESGD grade was observed in the treatment group (median 1, p = 0.0078), while there was no change in the control group (median 2). No significant weight change was observed in either group. CONCLUSION: Trophogast pellet was effective at promoting healing of mild ESGD in endurance horses.

Intradermal Testing Results in Horses Affected by Mild-Moderate and Severe Equine Asthma.

Equine asthma is an inflammatory respiratory disorder, classified as mild-moderate (MEA) and severe (SEA). SEA is characterized by recurrent exacerbations, consisting of dyspnea, coughing and exercise intolerance; MEA causes poor performance, occasional cough and mucus hypersecretion. Although a precise pathogenesis is not completely understood, allergic mechanisms are considered an important pathophysiological feature of equine asthma. In equine medicine, intradermal testing (IDT) is effective in identifying hypersensitivity to specific allergens. However, to date, the studies about IDT in asthmatic horses obtained contradictory results. This study aims to evaluate IDT responses in MEA and SEA horses and to identify the most significant allergens. Thirty-eight asthmatic horses were enrolled and underwent IDT using 50 allergens; reactions were evaluated at 30 min, 4, 24 and 48 h and were assigned a score from 0 to 4. In SEA horses, the most frequent and strongest reactions were observed at 30 min and 4 h, suggesting the involvement of type I hypersensitivity; in MEA horses, also type IV hypersensitivity seemed to play a major role. Insects, Dermatophagoides spp. and dog epithelium induced in MEA and SEA horses the most significant hypersensitivity responses and could therefore be considered as the main allergenic antigens in our geographic area.

Evaluation of Cardiac Arrhythmias before, during, and after Treadmill Exercise Testing in Poorly Performing Standardbred Racehorses.

The incidence of significant arrhythmias in sport horses and knowledge about their exact influence on athletic performance need to be clarified. The aims of the present study are to report the prevalence of cardiac arrhythmias during maximal treadmill exercise in poorly performing Standardbreds, and to investigate the possible relationship of demographic, cardiac and performance indices on premature complexes (PCs). Electrocardiographic Holter recordings before, during and after treadmill exercise testing of 158 poorly performing Standardbreds were analyzed retrospectively. Fifty horses did not have any type of arrhythmia. One hundred and eight horses had at least one type of arrhythmia, such as sinus arrhythmia (8.2%), sinoatrial block (3.2%), second-degree atrioventricular block (33.5%), supraventricular PCs (7.6%), and ventricular PCs (48.1%). A multiple regression analysis showed weak evidence that the occurrence of premature complexes decreases as the minimum heart rate increases, and a tendency for these arrhythmias to increase with increasing age and maximum lactate concentration. Our results suggest that PCs are frequent in poorly performing Standardbred racehorses, but further studies are necessary to clarify their role and clinical significance.