key: cord-0792716-wyrv3d83
authors: nan
title: 12(th) Annual European College of Equine Internal Medicine Congress
date: 2020-12-18
journal: J Vet Intern Med
DOI: 10.1111/jvim.15994
sha: c105af9d0c7e7f2f38420ea0a2a73762cac20ac2
doc_id: 792716
cord_uid: wyrv3d83

nan

pNfH concentrations were significantly higher in both serum (Padjusted= 0.001) and CSF (Padjusted= 0.003) of eNAD/EDM affected horses compared to unaffected horses. CSF pNfH concentrations were significantly higher in eNAD/EDM affected horses compared to unaffected horses (Padjusted= 0.003) but not significantly different from CVCM affected horses. Serum and CSF pNfH testing can provide useful antemortem diagnostic information regarding neurodegenerative diseases in neurologic horses.

ABSTRACT SESSION 2 FRIDAY 21 Evaluation of glycine and riboflavin in vitro as therapeutic agents for horses with atypical myopathy S. González-Medina * , R.J. Piercy

Comparative Neuromuscular Diseases Laboratory, The Royal Veterinary College of London, NW1 0TU, UK Equine atypical myopathy (AM) is an acute, severe and often fatal toxic rhabdomyolysis of grazing horses. Treatment efficacy in horses is limited and most therapies are empirical. Glycine and riboflavin have been tested in rodent models of hypoglycin A intoxication, but their suitability for affected horses has never been examined. This work aimed to test the hypothesis that riboflavin and glycine would protect cultured equine muscle-derived cells from the toxic effects of hypoglycin A's principal metabolite, methylene-cyclopropyl acetic acid (MCPA). Following calculation of toxicity range for MCPA, equine skeletal muscle-derived cells (2 replicates derived from 3 different horses) were incubated for 2h with either glycine or riboflavin at varying concentrations, before addition of 6mM MCPA. After 24h, cell viability was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) mitochondrial metabolism assay.

Riboflavin, but not glycine supplementation was significantly protective, partially mitigating the toxic effects of MCPA in vitro. Specifically, pre-treatment with 50μM (p=0.01) and 100 μM (p<0.001) riboflavin reduced cell toxicity by 42% and 74% respectively. Results obtained in vitro are encouraging and support further studies. Riboflavin supplementation is recommended for affected horses and might also be helpful as a preventive therapy in horses considered at high risk of sycamore material ingestion. Insulin dysregulated (ID) horses are prone to develop laminitis. Recent studies show promise that ID may be improved and laminitis may be prevented by the sodium-glucose linked cotransporter 2 (SGLT-2) inhibitor velagliflozin. The aim of the study was to investigate the metabolic responses and efficacy of velagliflozin treatment during the transition from winter hay feeding to pasture. Nineteen Icelandic horses were monitored. Six horses were metabolically healthy (H) and thirteen were insulin-dysregulated (ID), of which seven were treated three weeks prior to transition to pasture with velagliflozin (ID-V), once daily orally at 0.3 mg/kg body weight (BW), while the six others were treated with a placebo (ID-P). Parameters related to ID (e.g., insulin, glucose, and leptin) were measured at resting state and in response to oral glucose tests (OGT, 0.5 g glucose/kg BW, nasogastric tubing). After transition to pasture, in comparison to their pre-pasture metabolic status, ID-P horses exhibited a worsened ID, i.e., an increase of resting insulin and leptin levels. The baseline corrected AUC OGT insulin was increased in ID-P ((geomean, μIU/mL) 72.5 -> 86.7), slightly reduced in H (40.5 -> 33.6), and significantly decreased in ID-V (71. varied throughout the study with the highest in Dec and lowest in Feb. In this cohort using a 0.45 ml/kg OST, season appears to play a role in insulin response. ID status can vary throughout the year; therefore, interpretation of an OST in various seasons and in other breeds should be used as part of a more comprehensive diagnostic plan.

Key words: OST, insulin dysregulation, seasonal variation, equine Effect of α-tocopherol deficiency and repletion on skeletal muscle morphology in horses.

clinically normal, serum a-TOH deficient horses would demonstrate histologic and ultrastructural SC abnormalities, which would be ameliorated by a-TOH repletion. Our objectives were to quantify the effects of a-TOH deficiency and subsequent supplementation on SC mitochondrial staining, fiber morphology, fiber type composition, and ultrastructure. Blood and SC biopsies were obtained from 16 clinically normal a-TOH deficient adult horses before and 8 weeks after supplementation (n = 8; 5000 IU/day oral water dispersible a-TOH) or no supplementation (n = 8). A significant increase in serum a-TOH occurred in supplemented horses (1.2 ± 0.3 ug/mL to 2.6 ± 0.5 ug/ml, p < 0.0001). Prior to treatment, 4/8 control and 4/8 treatment horses were diagnosed with VEM based on blindly scored histopathologic abnormalities. Supplementation with a-TOH significantly improved scores for mitochondrial staining (p = 0.045), fiber size variability (p = 0.005) and fiber splitting (p < 0.0001), with a trend for increased fiber areas (p = 0.069) and no change in the type 1 fiber predominance. Electron microscopy demonstrated SC lipofuscin accumulation before and after a-TOH supplementation. In conclusion, histologic and ultrastructural changes exist in the SC of clinically normal a-TOH deficient horses, which improve but do not resolve following 8-week Smartphone-based ECGs are increasingly used in horses but have not specifically been assessed during atrial fibrillation (AF). In 23 healthy and 24 AF horses a standard electrocardiogram (ECG) (Televet100, Kruuse) was recorded at rest together with different smartphonebased ECGs: three AliveCor devices (veterinary AC-002, human AC-009 and self-adapted (larger spacing between electrodes) AC-009 device) were tested, each with 2 applications (AliveCorVet (veterinary) and Kardia (human)). The automatic AF detection algorithm of the Kardia application was checked for accuracy. ECGs were blinded and scored for baseline wander and presence of artefacts, P or f-wave visibility and overall quality. Smartphone-based ECGs were compared with the standard ECG using the non-parametric Friedman's 2-way analysis of variance by ranks. In SR only the self-adapted AC-009 scored equally compared to the standard ECG for all criteria, independent of the application used. In horses with AF the overall quality of the ECG was significantly lower for all smart-phone based devices compared to standard ECG and P and f-waves could hardly be identi- Atrial fibrillation (AF) may be a risk factor for Exercise-Induced Pulmonary Hemorrhage (EIPH) because of an increased pressure in the left atrium. The aim of this study was to evaluate if AF was associated with an increased likelihood of EIPH after a standardized exercise test (SET) to fatigue.

Ten Standardbred mares were included. The horses performed a SET on the treadmill before (sinus rhythm, SET1) and 25-44 days after induction of self-sustained AF (SET2). AF was induced by tachypacing using an implanted pacemaker. Endoscopy, including bronchoalveolar lavage (BAL), was performed 72-48 hours prior to and 24 hours after the two SETs, in addition endoscopic graduation of tracheal blood was performed 2 hours after each SET. Significant increase in BAL neutrophils was observed 24 hours after SET2 compared to before SET2 (p=0.043). Two horses had grade 1 blood in trachea 2 hours after SET2 and three horses had hemosiderophages in BAL 24 hours after SET2. Maximal velocity and HR did not differ between horses with and without visible blood in trachea after SET2. Previous studies have shown that horses with AF had tachypnea and increased pulmonary wedge pressure during exercise. In the present study 3/10 horses showed signs of EIPH when exercising in AF compared to sinus rhythm demonstrating a possible link between AF and EIPH. However, a larger study population is needed to finally conclude that AF predispose for EIPH. Furthermore, the link between EIPH, pulmonary pressure and AF needs to be further elucidated. Torsemide, a potent loop diuretic, has a good pharmacokinetic profile and produces marked diuresis after oral administration in horses. The aim of the study was to investigate the effects of torsemide on fractional excretion of Na+ (FENa+), K+ (FEK+) and Cl-(FECl-), and serum concentration of symmetric dimethylarginine (SDMA) in healthy horses. Torsemide (2mg/kg/q12 hours) was administered orally to 6 healthy mares for 6 consecutive days. Paired blood and urine samples were collected on days 0 (before torsemide administration), 1, and 6, at hours 0, 1, 3, 5, 7, 9 and 11 each day. Treatment effects

were assessed with repeated measures ANOVA and the post-hoc Bonferroni test with α at 0.05. Relative to Day 0 (mean±SD), FENa + day0 (0.08%±0.05) and FECl-day0 (0.55%±0.29) increased on Day Zaventem) of the entire jugular vein to screen for presence of thrombi and vascular abnormalities was performed using a 9-12 MHz linear transducer (9L-RS, GE Healthcare) starting 12-24h after catheter placement with a 48h interval until catheter removal and 12-24h after catheter removal with a 48h interval until leaving the hospital. At the level of insertion, distal outer catheter and distal inner catheter (Cavafix ® ) the medial jugular vein wall thickness was measured.

Results were analyzed using repeated measures. Mean wall thickness at the level of insertion, distal outer and inner catheter ranged between 0.56 and 1.20 mm but did not increase significantly over time (p=0.770, 0.425, 0.157,respectively). However in 60%(9/15) of the horses subclinical changes could be visualized. Thrombi were present in 40%(6/15), thickened venous valves in 33%(5/15) and a fibrin sleeve partially covering the catheter in 13%(2/15) of the horses.

Results indicate that repeated jugular vein ultrasonography can be used to detect early catheter-related changes and might therefore be useful to reduce the incidence and severity of thrombophlebitis in Atrial fibrillation (AF) can decrease performance in horses. Initially AF may be paroxysmal AF (PAF) with spontaneous onset and termination.

The short durations complicate diagnosis of AF. Implantable loop recorders (ILRs) are small ECG devices placed subcutaneously and programmed to detect arrhythmias by continuously measuring the RR interval. The objective of this study was to test whether ILRs can be used to diagnose PAF in horses.

We enrolled four Standardbreds with a history of intermittent decreased performance of unknown origin. All horses underwent a clinical examination, 24h ECG recording and an echocardiographic examination before implantation of an ILR. The ILRs were placed in the sixth left intercostal space and programmed to detect AF episodes. The horses went back to their regular work load and the ILRs were interrogated every two to six months.

All of the ILRs showed stable ECG signals throughout the study. In one horse, two PAF episodes of 7.87 and 7.33 hours duration were detected within 5 months. The ECG obtained by the ILR (Fig.1 ) confirmed the episodes. No other horses had AF episodes registered.

A previous study have shown that ILRs were able to register approximately 80 % of induced AF burden in horses and therefore we cannot rule out that the horses without any registered episodes did not experience PAF during the study.Undiagnosed PAF can have consequences in terms of disease progression and safety for horses and owners; therefore, this study suggests ILRs as an important ECG tool in the clinic for diagnosis confirmation. horses showed a significantly reduced end-diastolic ventricular internal diameter (LVIDd) (11.6±1.0 cm) but heart rate (50±13 bpm) was also significantly increased. LVIDd and fractional shortening (FS) increased progressively after cardioversion, although FS changes did not reach statistical significance. From 24h to 6 weeks in sinus rhythm, the pre-ejection period (102±24 and 88±17 m/s) decreased significantly, while the late diastolic LV myocardial velocity (A wave) (3.9±1.8 and 6.5 ±2.0 cm/s), early diastolic myocardial velocity (E wave) (18.2±4.0 and 19.9±4.2 cm/s) and the A/E ratio increased progressively. This study suggests that left ventricular systolic and diastolic function is reduced during AF and increases progressively after successful cardioversion.

The resulting reduced cardiac output may affect cardiac function during exercise. Therefore, assessment of both left ventricular and atrial function might be useful before the horse returns to full athletic performance.

First catheter-based high-density endocardial electroanatomical mapping of the right atrium in standing horses

In humans, catheter-based mapping of voltage and activation times of endocardial atrial bipolar electrograms (EGM) is used to identify arrhythmia mechanisms and to characterize electroanatomical substrates. We tested, whether this technique could be used in standing horses.

Four Standardbred horses (2 geldings, 2 mares, mean age 5 [4] [5] [6] [7] [8] [9] years, mean body weight 485 [440-550] kg) were sedated (0.01mg/kg detomidine, 0.01mg/kg butorphanol followed by constant rate infusion of 1.0 mg/ml xylazin). Through an 11F sheath in the jugular vein, a high-density multipolar grid catheter ( does not rely on such assumptions and may allow more accurate assessment of left atrial volume. To determine the intra-observer variability of equine left atrial volume measurement using a 3DE software analysis package. Graded datasets of the left atrium from athletic Thoroughbreds horses (n=24; 4-9yrs; 411-534kg), using a Vivid E9 with 3V transducer (GE Healthcare) were retrospectively analysed.

Selection criteria excluded horses with grade >3/6 cardiac murmurs.

Random generated order measurements were obtained by a single observer on 4 occasions. Real-time three-dimensional end-systolic (ESV) and end-diastolic (EDV) left atrial volumes were measured using the 4D Manual LVQ function v. 202 (EchoPAC, GE Healthcare). Intraobserver variability was assessed via calculation of 1 -the intra-class correlation coefficient (ICC) from random-effect linear models on EDV and ESV with horse added as the random effect (1-ICC horse ) in R (v 3.5.2) using the lmer and sjPlot packages. Average EDV was 593.1ml (range 349-1029ml) while ESV was 381ml (range 200-695ml), n=24. Lower observer variation (1-ICC horse ) for ESV measurements was observed (16%) compared to EDV (23%). There was good agreement between measurements (1-ICC horse <25%). The purpose of this study was to investigate the pulmonary artery distensibility index (PADI), quantifying the percent change in PAD during a cardiac cycle, for diagnosis of PHT in horses. 37 healthy horses, 94 horses with TR or PR and normal intracardiac pressure gradients, and 40 horses with PHT were chosen from the echocardiography database. PAD and PADI were measured and compared between groups using ANOVA and Tukey's post-hoc test.

Receiver operating characteristic curves served to determine the cutoff for diagnosis of PHT. The alpha-level was 0.05.

Horses with PHT had significantly larger PAD (7.21±0.99cm; mean ±SD) and smaller PADI (14.51±7.89%) than healthy horses (6.71 ±0.64cm; 20.56±4.22%) and horses with TR or PR but no PHT (6.84 ±0.68cm; 18.61±4.81%). At a cut-off of 7.7cm, PAD predicted PHT with a sensitivity (Sn) of 32% and a specificity (Sp) of 92% (AUC=0.604, p=0.048). At a cut-off of 15%, PADI predicted PHT with Sn=50% and Sp=89% (AUC=0.687, p=0.0003).

PAD and PADI were moderately specific but not very sensitive to diagnose PHT in horses. Hence, PADI may be used as a complementary index to diagnose PHT but cannot replace Doppler confirmation of PHT in the absence of valvular regurgitation. Advanced second or third-degree atrioventricular (AV) block can be treated by pacemaker implantation. Pacemaker rate-adaptability has typically been obtained by a built-in accelerometer. Closed-loop (CLS) stimulation is a new rate adaptive technology which is based on myocardial impedance changes due to altered sympathetic tone, and achieves a rate-adaptation closer to physiological needs. Automatic remote monitoring allows daily wireless based exchange of pacemaker functional parameters between the patient and an online server, which automatically sends warning messages to the clinician in case of suboptimal pacemaker function. Both CLS and remote monitoring

have not yet been investigated in veterinary medicine so far. In two miniature donkeys with symptomatic AV block, a rate-adaptive single chamber pacemaker with accelerometer, CLS and remote monitoring functionality (Eluna 8 SR-T, Biotronik) was implanted. A bipolar steroid eluting screw-in lead in the right ventricular apex was connected to the pacemaker. After full recovery, rate-adaptivity was assessed. In contrast to periods where no physical activity was present, during low-level exercise, increases in heart rate could be obtained with both the accelerometer and CLS function. During periods of stress, without any physical activity, only the CLS function produced physiological heart rates. With a receiver nearby the donkey (<4m distance), successful wireless remote monitoring was obtained in both cases with exchange of data to the clinician.

CLS functionality successfully allowed to achieve physiologicallypaced heart rate adaptation in relation to actual needs. It also resulted in rate response without physical motion. Remote monitoring allowed automatic reporting of pacemaker function which facilitate follow-up. In equine adults iron is a sensitive marker of systemic inflammation.

The aim of our study was to determine plasma iron concentration in healthy equine neonates, to assess its utility as an early inflammatory marker to predict Systemic Inflammatory Response Syndrome (SIRS) and its prognostic value in sick foals. Plasma iron was determined by colorimetric assay (Olympus AU400, Hamburg, Germany) in 225 neonatal foals (<14 days). Foals were divided in three groups: SIRS, non-SIRS and healthy controls. SIRS was defined as two or more of the following: (1) hyper-or hypothermia (rectal temperature >39.2 C or < 37.2 C), (2) leukocytosis or leukopenia (peripheral white cell count > 12.5 x 10 3 /μL or < 4 x 10 3 /μL), or >10% immature (band) neutrophils, (3) tachycardia (> 120 beats/min), and (4) Faecal samples did not reveal other causative pathogens than ECoV.

All horses recovered but two showed prolonged shedding (4 and 10 weeks). Out of 79 horses at the facility the Icelandic horse originated from 26% showed clinical signs consistent with ECoV infection with PCR-confirmed infection in 43/79. All despite two horses recovered and cleared the virus not later than week 13. A raise in antibody titer could be demonstrated in 5/11 horses. Consecutive outbreaks after contact with infected horses stress the viruse's infectious potential. In conclusion, enteric disease caused by ECoV was found in horses with epidemic character in Austria. The infection spreads rapidly and should be considered as a differential diagnosis when compatible clinical signs exist. Range=0-0.7; p=0.68)). Of these in-contacts, 29% and 26% had titres >0.4 for antigen A and C, respectively, suggesting ongoing exposure.

This modest study suggests that use of serum titres may not be valuable to identify horses that have likely had long-term carrier status and chondroids and warrants further work. Key words: Strangles, ELISA, equine. Using next generation sequencing we have previously shown that eca-miR-331, -100, and -1 were differentially expressed microRNAs (miRNAs) in serum of sarcoid-affected vs control horses. The aim of the current study was to validate the identified candidate miRNAs as serum biomarkers for equine sarcoid (ES) disease in a larger cohort study composed of horses and donkeys with sarcoids and controls with or without other types of skin tumors by qRT-PCR. MiRNAs were extracted from serum of ES-affected horses (n = 56) and donkeys (n = 13), control horses (n = 60) and donkeys (n = 9), and horses with other skin tumors (melanoma, squamous cell carcinoma) (n = 20). Hemolysis in serum samples was evaluated using the hemolysis index (Cobas 6000). The extracted miRNAs were subjected to qRT-PCR with primers specific for eca-miR-331, -100, and -1. Statistical analysis of variance showed no effect of breed, age, or gender on expression of the examined miRNAs.

Hemolysis did not influence the expression of eca-miR-331. In contrast, the other two candidate miRNAs were significantly influenced by hemolysis. As in the pilot study, there was a significant upregulation of eca-miR-331 in ES-affected equids compared to control equids without tumors. A statistically significant difference in miRNA expression for eca-miR-100 and -1 in ES-affected vs control animals could however not be confirmed. Eca-miR-331 was also upregulated in serum of horses with other skin tumors, suggesting a role of this miRNA as a biomarker for equine skin tumors in general not only restricted to equine sarcoids.

Keywords: microRNA, biomarker, equine sarcoid disease, equine skin tumors Outcome of an intravitreal injection of a microdose of gentamicin for treatment of ERU and association with Leptospiral status in the west of France Tanguy Hermange 1,2 , Anne Courouce 1,2 Atlantique (Oniris), Université Bretagne Loire (UBL), Nantes F-44307, France; 2 CISCO (Centre International du Cheval d'Oniris), Ecole nationale vétérinaire, agro-alimentaire et de l'alimentation Nantes-Atlantique (Oniris), Nantes F-44307, France

The use of an intravitreal injection of a microdose (4 mg) of gentamicin is increasing by equine practitioner in ERU cases. Our study aims to evaluate the association between the outcome of an intravitreal injection of a microdose of gentamicin and leptospiral-ERU status. To assess leptospiral status, both a Leptospiral microscopic agglutination titres ratio between aqueous humour and serum (C-value) superior to 4, or a positive Leptospiral polymerase chain reaction (PCR) on aqueous humour, were used. All the horses were followed up for at least 12 months. As a complete ophthalmologic exam was not available for each horse during the follow up, only horses with easily recognizable active signs of ERU by the referring vet and/or owner were included in this study (insidious ERU excluded). A total of 19 horses were included.

Regarding leptospiral-associated ERU status, 58% (11/19) were positive and 42% (8/19) were negative. On short term, all horses responded well to intravitreal injection without any recurrence during the first 6 months. The majority (10/11) of horses positive to leptospiral-ERU did not showed any signs of recurrence for at least 12 months. On the other side, 4/8 horses with non-leptospiral ERU showed some signs of partial response after 6 months with either recurrence or signs of active insidious form of ERU. These preliminary results suggest that good short-term outcome observed with intravitreal injection of microdose of gentamicin is not dependent on leptospiral-ERU status. However, the leptospiral-ERU status may influence long term outcome. Thirty-six thoroughbred racehorses in active training were enrolled in the study; a control group (n=11) with normal BAL values, a RGT (n=12) and a serum treatment group (n=13). An endoscopy including BAL was performed before (T0), after a six-week treatment period including 12 intramuscular injection of RGT or serum (T6) and as a follow-up 10 weeks after last treatment (T16).

No difference between any of the time point was found for the control group. A significant decrease in BAL neutrophils (RGT p<0.01; serum p<0.01) and mast cells (RGT p=0.02; serum p<0.01) was found for both treatment groups between T0 and T6. A significant difference between T0 and T16 was found for BAL neutrophils in the serum treatment group (p=0.05) and BAL mast cell groups (RGT p<0.01; serum p=0.03). No difference was found between T0 and T16 for BAL neutrophils for the RGT group (p=0.49).

Preliminary results from this study showed that intramuscular treatment with either RGT or serum was effective in reducing BAL neutrophils and Eleven clinically healthy horses (mean 9.3 ± 5.4 years) and 11 horses (mean 9.9 ± 6.5 years) with clinical acute kidney injury stage 2 and 3 (according to AKIN criteria for human AKI) were included in the study. Metabolomic analysis was performed on serum samples, using Quadrupole time-of-flight mass spectrometry. Statistical analysis was performed by the Student t-test and PCA analysis (MarkerView™).

Differences between metabolomes in both groups (P<0,05) were demonstrated for 514 metabolites. There were significant differences between the two groups in metabolites belonging to the following pathways: vitamin D3 metabolism (e.g. calcidiol, calcitriol) and leukotri- analysis. The distribution of comet tail artefacts was significantly different in different intercostal spaces (ICS) before BAL. The cranial intercostal spaces were more affected (left side: 5 th ICS: 7, 6 th ICS: 15, 7 th ICS: 10 horses had artefacts; right side: 5 th ICS: 16, 6 th ICS: 9, 7 th ICS: 6 animals showed this abnormality). The overall number of comet tail artefacts was significantly higher after BAL (47% increase).

When hemithoraces were compared separately, the difference was also significant between before and after results. Significant differences were found in several individual ICS between before and after results (left side: 4 th , 5 th , 8 th , 10 th , and 12 th to 16 th ; right side: triceps, 4 th , 6 th , 7 th and 10 th to 12 th ). Comet tail artefacts showed a characteristic pattern before BAL, being more frequent in the cranioventral part of the thorax. BAL affected thoracic ultrasonographic findings in this study population. To avoid misinterpretation of findings, it is rec- Three-dimensional datasets of the LV were acquired prospectively from 18 National Hunt Thoroughbred racehorses in training (right parasternal long axis view) using a Vivid E9 with a 4V-D transducer.

Blinded to horse details and any previous results, offline 2D and 3DE analyses were performed using the same three non-consecutive cardiac cycles. One-way repeated measures ANOVA compared methods for LV estimation; coefficients of variation (CV) and Pearson's correlation coefficients were calculated to determine intra-observer measurement (repeated measurements of same examination) and acquisition (repeated acquisitions of same horse) repeatability. and Doppler 1295ml (s.d. 206)). Intra-observer measurement variability was low for all methods (CV 2.2-6.2%). Intra-observer acquisition variability was slightly greater then measurement variability, for all methods. Pearson's correlation coefficient (r = 0.90) and CV (6.8%) showed superior acquisition repeatability of 3DE. In conclusion, estimation of LV volumes by 3DE is feasible, shows greater repeatability compared to current methods, and has the potential to allow accurate longitudinal assessment of LV size. (IDQ p180, Biocrates, Innsbruck) targeting metabolites involved in a broad range of pathways was then used for metabolomic analysis of plasma samples from the time-points 0, 120 and 180 minutes. Using linear models concentrations of metabolites associated with inflammation like tryptophan and kynurenine were shown to significantly increase over time (FDR-adjusted P<0.01). In further metabolites, a linear relationship to the AUCinsulin was detected. For instance arginine, an amino acid known for its essential role in vasodilation, was found to be significantly lower in horses with higher insulin levels (FDR-adjusted P<0.05).

In a reversed approach, predictive models were successfully used to demonstrate the ability of such a dataset to differentiate between horses with high and low insulin response. These results suggest that an inflammatory response was triggered during OGT independently of the insulin status of the horse. Metabolites associated with the insulin levels could be relevant to better understand the pathomechanisms of ID, as biomarkers for this disease, and as potential therapeutic targets. If these results were confirmed by further experiments, a set of these metabolites could eventually be brought to on-site diagnostic platforms. A total of 48 horses were included, 24 healthy and 24 sick horses referred to two veterinary teaching hospitals. Horses were evaluated as SIRS positive or negative according to a previous paper. Blood samples were collected in healthy horses only once, and at admission (T0), 24(T1), 48(T2), 72(T3), 96(T4) hours after admission in sick horses. PCC was evaluated using the method by Levine et al. Data were analyzed for distribution using the KS test and results were expressed as median ±SE. Kruskal-wallis and Dunn's multiple comparisons tests were used to verify differences between healthy and SIRS positive horses at different sampling times. P value was set at <.05. The ROC curve was performed to evaluate the best cut-off for the diagnosis of SIRS.

The 24 healthy horses presented a normal physical examination and laboratory data within reference ranges and were included in the control group. Three/24 sick horses were not positive for SIRS score and were excluded. The PCC (nmol/mL/mg) was 0.052±0.008 in healthy horses and 0.312±0.007(T0), 0.079±0.032(T1), 0.093±0.036(T2), 0.081±0.034(T3), 0.084±0.027(T4) in SIRS positive animals. Differences were obtained between healthy and SIRS positive horses at T0, T1 and T2, and in SIRS positive horses between T0 vs T72 and T96.

The best cut-off found was 0.128 nmol/mL/mg with sensitivity of In this study, we evaluated matrix-metalloproteinase-9 (MMP-9) in plasma and peritoneal fluid as a sepsis marker in equine colic patients.

Results of sepsis scoring were compared to the concentrations of MMP-9. A modified sepsis scoring including general condition, heart and respiratory rate, inner body temperature, mucous membranes, white blood count (WBC) and ionized calcium was performed in 47 horses presented with colic. Using this scoring system, horses were classified as negative (n = 32, ≤ 6/15 points), questionable (n = 8, 7-9/15 points) or positive (n = 6, ≥ 10/15 points) for sepsis. MMP-9 concentrations were evaluated in plasma and peritoneal fluid using species-specific sandwich ELISA kits. In a linear discriminant analysis, all parameters of sepsis scoring apart from calcium separated well between sepsis severity groups (P<0.05). A significant influence of overall sepsis scoring on MMP-9 was found for peritoneal fluid (P = 0.007) with a regression coefficient of 0.131, while no association was found for plasma (P = 0.078). A MMP-9 concentration of >110 ng/ml in peritoneal fluid was found to be the ideal cut-off to identify positive sepsis scoring (≥ 10/15 points; sensitivity of 85.7 % and specificity of 87.5 %). MMP-9 was found to be a biomarker of high diagnostic value for sepsis and endotoxemia in equine colic. Peritoneal fluid seems preferable in comparison to plasma.

As abdominocentesis is commonly performed in the diagnostic workup of equine colic, a pen-side assay would be useful and easy-to perform diagnostic support in the decision for surgery and prognostic estimation.

Key words: MMP-9, sepsis, colic, endotoxemia, horse Photodermatitis rarely occurs in horses and was reported after ingestion of different plants or chemicals and in patients with hepatic insufficiency. Nine horses from three different stables presented with variable degrees of erythema, crusting and necrosis of unpigmented skin at the head and prepuce. Extremities were unaffected. Horses were of different breeds with a median age of 15 ± 5.9 years. 1/9 horses showed a mild leukocytosis at admission. Liver enzymes were within the reference ranges in all horses. Ocular changes were seen as follows: blepharitis 3/9, conjunctivitis 7/9, corneal edema without additional signs of keratitis and/or uveitis 2/9, corneal edema with signs of uveitis 1/9 and photophobia 4/9. Only one horse developed a fluoreszein positive corneal erosion within 4 days. Skin biopsy (1/9) revealed a moderate to severe acute, eosinophilic and lymphocytic dermatitis with severe dermal edema and vasculitis. All stables fed hay from the same hay distributer with a high content of parsnip (plants, seeds, roots). Parsnip is widespread in Europe and contains furocoumarins, a family of photodynamic pigments, which may cause primary photosensitization, corneal edema and keratoconjunctivitis. Insulin Dysregulation (ID) encompasses different disorders like hyperinsulinemia and insulin resistance. The aim of this study was to determine if ID is associated with altered expression of key proteins of the insulin signaling cascade (ISC) in liver tissue under basal and/or stimulated conditions. Twelve Icelandic horses were subjected to an Oral Glucose Test (OGT) with 1 g/kg bwt glucose administered via nasogastric tube. Liver biopsy samples were taken at basal conditions and at 120 minutes of the OGT. Expression levels of AMPK α, InsR, mTOR and PKB as well as their extent of phosphorylation were determined by Western Blot. Insulin levels at 120 minutes measured by ELISA, revealed that 6 horses were insulin-dysregulated while 6 were not. No significant differences in basal protein expression could be identified by two-way repeated measures ANOVA with Holm adjustment for multiple testing between groups. Phosphorylated insulin receptor (pInsR) was expressed at significantly higher levels upon glucose stimulation (p=0.011), whereas phosphorylated AMPK α was downregulated (p=0.036). Linear regression of pInsR against insulin under stimulated conditions revealed that in healthy horses there was a significant positive linear relationship between both variables (p=0.021) while it was negative in dysregulated horses (p=0.015).

These results indicate that while the expression levels of these key proteins of the ISC do not seem significantly different in insulindysregulated horses, the phosphorylation of InsR appears impaired, possibly indicating an insulin resistance. As insulin-dysregulated horses are not necessarily insulin-resistant, it remains to be investigated if this is a tissue specific response.

PCC seems to be a marker of SIRS posi-1

suggesting that the intoxication depends on the year and that the number of cases seems to increase. Clinical signs associated with acorn intoxication were signs of circulating shock (depression, tachycardia, abnormal mucous membrane, tachypnée), digestive signs (diarrhea, ileus, colic), and abnormal temperature. Clinical pathological findings included increased PCV, WBC, creatinine, BUN, GGT, AST, CK and decreased albumin. Overall 44% horses survived; 13/14 of non-surviving horses died during the first 48 hours. Findings significantly associated with non-survival were: older age, hemorrhagic diarrhea, heart rate, PCV, creatinine, blood lactate, and thickness of the colon wall at ultrasonography. Using threshold of PCV>60%, Lactate>4.5mmol/L, Creatinine>26mg/L, colon wall thickness>22mm, positive predictive value for non-survival was above 90% for each parameter. Acorn intoxication seems to increase in the West of France

A reliable method of right ventricular (RV) volume calculation in the horse does not exist. This study evaluated the feasibility and reliability of three-dimensional echocardiography (3DE) for measuring rightventricular volumes in twelve healthy Thoroughbreds in training (ages 3-10). Left parasternal long axis (L-RV) and right parasternal rightventricular outflow tract views (R-RV) were acquired by two observers in unsedated horses using a GE Vivid E9 ultrasound machine with a 3V-D transducer. images were taken at frame rates between 12.2-15.2 FPS. Analysis was blinded, randomized and performed with the 4D Auto RVQ package, GE EchoPAC Software (v.202), with both automatic and manual border tracking. Measurements were calculated as an average of 3 consecutive cycles. Reliability of 3D methods was assessed by calculating the inter-observer and intra-observer within-day and between-day acquisition variability and measurement variability, reported as the coefficient of variation (CV). Additionally, 3DE stroke volumes were compared to pulsed-wave Doppler derived values. Volumetric analysis was possible from all recordings. The L-RV singlebeat automatic method was the most reliable with low-moderate variability for all measures (CV 6.8-17.56%). Reliability of other methods ranged from low to high. Generally, endocardial border tracking was inaccurate based on visual assessment, and 3DE methods underestimated stroke volumes compared to Doppler, with differences of 293 ± 225 ml to 612 ± 315 ml (mean±SD). These results suggest 3DE is a feasible and repeatable method, but poor endocardial tracking of the ventricular free-wall may limit accurate identification of changes in ventricular volumes longitudinally and should be further investigated.Keywords: 3-dimensional echocardiography; right-ventricle; volume Is MMP-9 a valuable diagnostic marker of sepsis and endotoxemia in equine colic?Ann Kristin Barton 1 , Ina-Gabriele Richter 2 , Tanja Ahrens 1 , Abdollah Alalwani 1 , Dirk Barnewitz 2 and Heidrun Gehlen 1 Horses were treated according to severity of clinical symptoms systemically with flunixine meglumine (1.1 mg/kg BW 1-2x/day) or prednisolone (1 mg/kg BW 1x/day). Topically, either gentamicin (3x/day), dexamethasone (2-3x/day) and/or atropine (1x/day) were used. Skin care was provided with almond oil or dexpanthenol (2x/day). All horses were kept in a dark environment or treated with sunscreen and face-masks. Duration of treatment varied from 6 to 30 days (median 11.3 days). ples T-Test using horses as their own controls. Significance was set at P < 0.05. The horses remained healthy during the study period. TW neutrophil percentage was higher after the shavings period (mean ± SD; 32.8 ± 25.0) compared to first (17.2 ± 15.9; P = 0.009) or second peat period (13.1 ± 15.9; P < 0.001). BALF neutrophil percentage was lower after the second peat period (1.6 ± 1.1) compared to the shavings period (3.4 ± 3.1; P = 0.002) or first peat period (2.7 ± 2.2; P = 0.008).These preliminary results suggest that wood shavings increase airway neutrophilia detected in tracheal secretions compared to peat bedding. The result might be helpful in choosing bedding material for horses with equine asthma.