Epidemiological survey and risk factors associated with Paslahepevirus balayani in equines in Europe.

Paslahepevirus balayani (HEV) is an important emerging zoonotic virus in Europe. Although domestic pigs and wild boar are the main reservoirs of this pathogen, susceptibility to this virus has been confirmed in a growing number of animal species, including equines. However, their role in the epidemiology of this virus remains poorly understood. Our aim was to assess HEV circulation and identify potential risk factors associated with exposure in equid species in different European countries. A total of 596 equines, including 496 horses, 63 donkeys and 37 mules/hinnies bred in four European countries (Spain, Italy, United Kingdom and Ireland) were sampled. Thirty-three animals (5.5%; 95%CI: 3.7-7.4) had anti-HEV antibodies. Seropositivity was found in 4.6% of horses, 11.1% of donkeys and 8.1% of mules/hinnies tested. By country, 6.3%, 5.4%, 5.0% and 4.0% of the equines sampled in Spain, Italy, United Kingdom and Ireland, respectively, were seropositive, respectively. Statistical analysis showed that "species" and "drinking water from ponds and streams" were potential risk factors associated with HEV seropositivity in equines in Europe. HEV RNA was not detected in any (0.0%; 95%CI: 0.0-1.8) of the 202 equines tested. Our results provide evidence of a low, spatially homogeneous and widespread viral circulation that is not equal across species in equid populations in the European countries analyzed and indicate that these species appear to play a limited role in the epidemiology of this virus. Further studies are required to elucidate the differences in seroprevalence between donkeys, mules/hinnies and horses and to determine the risk of zoonotic transmission of this pathogen from equid species.

Decellularized Graft for Repairing Severe Peripheral Nerve Injuries in Sheep.

BACKGROUND AND OBJECTIVES: Peripheral nerve injuries resulting in a nerve defect require surgical repair. The gold standard of autograft (AG) has several limitations, and therefore, new alternatives must be developed. The main objective of this study was to assess nerve regeneration through a long gap nerve injury (50 mm) in the peroneal nerve of sheep with a decellularized nerve allograft (DCA). METHODS: A 5-cm long nerve gap was made in the peroneal nerve of sheep and repaired using an AG or using a DCA. Functional tests were performed once a month and electrophysiology and echography evaluations at 6.5 and 9 months postsurgery. Nerve grafts were harvested at 9 months for immunohistochemical and morphological analyses. RESULTS: The decellularization protocol completely eliminated the cells while preserving the extracellular matrix of the nerve. No significant differences were observed in functional tests of locomotion and pain response. Reinnervation of the tibialis anterior muscles occurred in all animals, with some delay in the DCA group compared with the AG group. Histology showed a preserved fascicular structure in both AG and DCA; however, the number of axons distal to the nerve graft was higher in AG than in DCA. CONCLUSION: The decellularized graft assayed supported effective axonal regeneration when used to repair a 5-cm long gap in the sheep. As expected, a delay in functional recovery was observed compared with the AG because of the lack of Schwann cells.

Ferritin But Not Iron Increases in Retina Upon Systemic Iron Overload in Diabetic and Iron-Dextran Injected Mice.

Purpose: Iron overload causes oxidative damage in the retina, and it has been involved in the pathogeny of diabetic retinopathy, which is one of the leading causes of blindness in the adult population worldwide. However, how systemic iron enters the retina during diabetes and the role of blood retinal barrier (BRB) in this process remains unclear. Methods: The db/db mouse, a well-known model of type 2 diabetes, and a model of systemic iron overload induced by iron dextran intraperitoneal injection, were used. Perls staining and mass spectrophotometry were used to study iron content. Western blot and immunohistochemistry of iron handling proteins were performed to study systemic and retinal iron metabolism. BRB function was assessed by analyzing vascular leakage in fundus angiographies, whole retinas, and retinal sections and by studying the status of tight junctions using transmission electron microscopy and Western blot analysis. Results: Twenty-week-old db/db mice with systemic iron overload presented ferritin overexpression without iron increase in the retina and did not show any sign of BRB breakdown. These findings were also observed in iron dextran-injected mice. In those animals, after BRB breakdown induced by cryopexy, iron entered massively in the retina. Conclusions: Our results suggested that BRB protects the retina from excessive iron entry in early stages of diabetic retinopathy. Furthermore, ferritin overexpression before iron increase may prepare the retina for a potential BRB breakdown and iron entry from the systemic circulation.

Sample stability and heparin interference in ionized calcium and ionized magnesium measurements in horses using the Stat Profile Prime Plus co-oximetry electrolyte analyzer.

BACKGROUND: The determination of iCa and iMg is important in veterinary medicine, but their immediate determination in whole blood is not always possible. Their stability in other sample types and the existence of interferences must be evaluated before its use. OBJECTIVES: We aimed to analyze the effects of storage time on the stability of iCa, iMg, and other analytes in whole blood, plasma, and serum samples in horses and assess the interference of heparin in these measurements. METHODS: Whole blood, heparin-plasma, and serum samples from 10 horses were stored at 4°C and analyzed 1, 2, 3, 4, 5, 6, 7, 8, 24, 48, and 168 hours after sample collection using the Stat Profile Prime Plus Vet equipment (Nova Biomedical, Waltham, MA, USA). Results were analyzed by ANOVA or mixed-effect models. RESULTS: The concentration of iCa, iMg, total calcium (tCa), total magnesium (tMg), and the ratios iCa/tCa and iMg/tMg did not differ up to 168 hours when compared to the initial time. Total Ca, iMg, and tMg were not significantly different among sample types, but iCa concentrations were slightly but significantly lower in plasma. Freezing at -20°C did not affect iCa, iMg, tCa, and tMg. The pH increased in serum and plasma after 8 hours, and a mild negative correlation existed between plasma iCa concentration and pH. A negative correlation was observed also between the ratios iCa/tCa or iMg/tMg and pH in plasma and serum. A significant decrease in iCa and iMg was detected when comparing homemade syringes at high heparin concentration (~200-300 U heparin/mL) and commercial lithium-heparin tubes (20-30 U/mL). CONCLUSIONS: Samples stored at 4°C can be used to determine iCa and iMg concentrations up to 7 days after collection. Other metabolites are stable for up to 8 hours; heparin interference should be taken into account if using homemade heparin syringes.

Seroepidemiological study of Toxoplasma gondii in equids in different European countries.

Toxoplasmosis, caused by the obligate intracellular protozoan Toxoplasma gondii, is a worldwide parasitic zoonosis. A cross-sectional study was carried out to determine the exposure to T. gondii in equids in Europe. Serum samples from 1399 equids (1085 horses, 238 donkeys, and 76 mules/hinnies) bred in four European countries (Italy, Spain, United Kingdom [UK], and Ireland) were collected during the period of 2013-2021. The overall seroprevalence of T. gondii was 18.9% (95% Confidence Interval [CI]: 16.9-21.0) by using the modified agglutination test (MAT) at a cut-off of 1:25. Seropositivity by country was 27.1% in Italy, 16.6% in Spain, 12.0% in UK and 7.0% in Ireland. Anti-T. gondii antibodies were detected in 12.8% of the horses, 43.7% of the donkeys, and in 28.9% of the mules/hinnies. A Generalized Estimating Equation (GEE) analysis was carried out to study the associations between seropositivity and explanatory variables related to individuals, herds, and management measures on these herds, selected based on the bivariate analysis. The risk for being seropositive for T. gondii was 5.3 and 2.7 times higher in donkeys and mules/hinnies than in horses, respectively. In addition, significantly higher seropositivity was observed in horses from herds that used disinfectants less than once a week (13.9%; p = 0.038, odds ratio [OR] = 1.6; 95% CI: 1.03-2.62) compared with those from herds that performed weekly disinfection of the facilities (9.4%). This is the first large-scale seroepidemiological study on T. gondii comprising horses, donkeys, and mules/hinnies in Europe and the first report of T. gondii exposure in horses from Ireland and UK. We found a widespread distribution of T. gondii among equid populations in different European countries. The seroprevalence found in these species, especially in donkeys and mules/hinnies, highlights the potential risk of human infection through the consumption of their raw/undercooked milk or meat.

Repair of Long Peripheral Nerve Defects in Sheep: A Translational Model for Nerve Regeneration.

Despite advances in microsurgery, full functional recovery of severe peripheral nerve injuries is not commonly attained. The sheep appears as a good preclinical model since it presents nerves with similar characteristics to humans. In this study, we induced 5 or 7 cm resection in the peroneal nerve and repaired with an autograft. Functional evaluation was performed monthly. Electromyographic and ultrasound tests were performed at 6.5 and 9 months postoperation (mpo). No significant differences were found between groups with respect to functional tests, although slow improvements were seen from 5 mpo. Electrophysiological tests showed compound muscle action potentials (CMAP) of small amplitude at 6.5 mpo that increased at 9 mpo, although they were significantly lower than the contralateral side. Ultrasound tests showed significantly reduced size of tibialis anterior (TA) muscle at 6.5 mpo and partially recovered size at 9 mpo. Histological evaluation of the grafts showed good axonal regeneration in all except one sheep from autograft 7 cm (AG7) group, while distal to the graft there was a higher number of axons than in control nerves. The results indicate that sheep nerve repair is a useful model for investigating long-gap peripheral nerve injuries.

Repair of Long Nerve Defects with a New Decellularized Nerve Graft in Rats and in Sheep.

Decellularized nerve allografts (DC) are an alternative to autografts (AG) for repairing severe peripheral nerve injuries. We have assessed a new DC provided by VERIGRAFT. The decellularization procedure completely removed cellularity while preserving the extracellular matrix. We first assessed the DC in a 15 mm gap in the sciatic nerve of rats, showing slightly delayed but effective regeneration. Then, we assayed the DC in a 70 mm gap in the peroneal nerve of sheep compared with AG. Evaluation of nerve regeneration and functional recovery was performed by clinical, electrophysiology and ultrasound tests. No significant differences were found in functional recovery between groups of sheep. Histology showed a preserved fascicular structure in the AG while in the DC grafts regenerated axons were grouped in small units. In conclusion, the DC was permissive for axonal regeneration and allowed to repair a 70 mm long gap in the sheep nerve.

Plasma-Ionized Magnesium in Hospitalized Horses with Gastrointestinal Disorders and Systemic Inflammatory Response Syndrome.

Magnesium disorders in horses with gastrointestinal disorders or systemic inflammatory response syndrome (SIRS) are scarcely characterized. The purpose of the study was to explore the association of magnesium disorders with diagnosis, SIRS and mortality in horses admitted to a referral equine hospital. In total, 75 sick horses were included in an observational prospective study and classified as: obstructive (n = 17), inflammatory (n = 10) and ischemic gastrointestinal disorders (n = 12), and other non-gastrointestinal systemic disorders (n = 36). All sick horses were also divided according to the presence (n = 26) or absence of SIRS, and survival to discharge from hospital (survivors (n = 61) and non-survivors (n = 14). In addition, 26 horses were included as controls. On admission, mean (iMg) (95% confidence interval (CI)) in the SIRS group (0.47 (0.43-0.50 mmol/L)) was within the normal range (0.4-0.6 mmol/L). The obstructive group had lower (iMg) compared to the control group (0.44 (0.38-0.51 mmol/L) vs. 0.56 (0.50-0.61 mmol/L); p = 0.001). In total, 8 out of 17 (47%) horses with obstructive lesions presented with hypomagnesemia compared to controls (4% (1/26)) (p = 0.001). In conclusion, hypomagnesemia was more prevalent on admission in horses in the obstructive group, and to a lesser extent, in the inflammatory and ischemic groups. In contrast to human ICU patients, the proportion of hospitalized horses with hypomagnesemia was not associated with mortality.

Effect of Diet Supplementation with the Mycotoxin Binder Montmorillonite on the Bioavailability of Vitamins in Dairy Cows.

The objective of this study was to determine the effect of the mycotoxin binder montmorillonite (MMT) supplemented in the diet of dairy cows on the bioavailability of vitamins A, D, E, B1 and B6. Six multiparous Holstein-Friesian cows were used in a crossover design with two periods. Treatments were a control diet with or without MMT. Vitamins were infused individually into the abomasum through the ruminal cannula. Blood samples were collected from the jugular vein at 0, 1, 2, 3, 4, 6, 9, 12, 24 and 48 h after the administration of each vitamin. Results showed that vitamin A reached maximal concentration (Tmax) at 5.3 h after dosing, the maximal concentration (Cmax) was 1.2 times higher than the basal concentration (Cbasal), and the area under the curve (AUC) was 739 arbitrary units. Vitamin B6 reached the Tmax at 13 h after dosing, the Cmax was 1.4 times higher than the Cbasal, and the AUC was 222 arbitrary units. No differences were observed in Cbasal, Tmax, Cmax and AUC of vitamin A and B6 between control vs. MMT-supplemented cows. Plasma concentrations of vitamins D, E and B1 had no concentration peaks, and were not affected by MMT addition. The lack of a response suggests that their plasma concentration may be tightly regulated. Results of this study do not show evidence that MMT affects the bioavailability of vitamins A and B6 in vivo.

Peritoneal bile acids concentration in adult horses with hepatic and gastrointestinal disorders.

BACKGROUND: Peritoneal bile acids concentration (PBAC) has not been previously reported in horses. A case of liver lobe torsion in which increased PBAC was detected prompted us to study PBAC in horses. OBJECTIVES: (a) To determine a reference range of PBAC in horses; (b) to compare PBAC from horses with either hepatic or gastrointestinal disease and healthy horses and (c) to assess the prognostic and diagnostic values of PBAC. STUDY DESIGN: Prospective case-control. METHODS: Prospective observational clinical study. Bile acids concentrations were measured in both plasma and peritoneal fluid in selected clinical patients with hepatic or gastrointestinal disease (n = 108) and healthy horses (n = 11). Sixty-eight of 108 patients survived to hospital discharge, and the remaining 40 were nonsurvivors. Additionally, other haematological and biochemistry analyses were performed. RESULTS: Sick horses were classified according to diagnosis into hepatic (n = 13), gastrointestinal (GI) obstructive (n = 48) and GI ischaemic-inflammatory (n = 47) groups. The hepatic group had significantly higher PBAC (6.8 [2.3-9.4]; median [IQR]) than the control (1.0 [0.6-1.5]) and GI obstructive groups (1.2 [0.8-1.7] µmol/L; P < .001). Moreover, the GI ischaemic-inflammatory group (3.3 [1.4-5.5]) also had significantly higher values than the control and GI obstructive groups (P < .001). Regarding outcome, the nonsurvivor group (n = 40) had significantly higher median PBAC value than the survivor group (n = 68, 4.1 [1.6-6.5] vs 1.3 [0.8-3]; P < .001). MAIN LIMITATIONS: A higher number of horses with abdominal disease is required to confirm the clinical significance of these findings. CONCLUSIONS: PBAC may have a role in the diagnosis of hepatic and gastrointestinal disease and as a prognostic tool in horses with abdominal pain.

Widespread Circulation of Flaviviruses in Horses and Birds in Northeastern Spain (Catalonia) between 2010 and 2019.

The surveillance for West Nile virus (WNV) in Catalonia (northeastern Spain) has consistently detected flaviviruses not identified as WNV. With the aim of characterizing the flaviviruses circulating in Catalonia, serum samples from birds and horses collected between 2010 and 2019 and positive by panflavivirus competition ELISA (cELISA) were analyzed by microneutralization test (MNT) against different flaviviruses. A third of the samples tested were inconclusive by MNT, highlighting the limitations of current diagnostic techniques. Our results evidenced the widespread circulation of flaviviruses, in particular WNV, but also Usutu virus (USUV), and suggest that chicken and horses could serve as sentinels for both viruses. In several regions, WNV and USUV overlapped, but no significant geographical aggregation was observed. Bagaza virus (BAGV) was not detected in birds, while positivity to tick-borne encephalitis virus (TBEV) was sporadically detected in horses although no endemic foci were observed. So far, no human infections by WNV, USUV, or TBEV have been reported in Catalonia. However, these zoonotic flaviviruses need to be kept under surveillance, ideally within a One Health framework.

Evaluation of Plasmatic Procalcitonin in Healthy, and in Systemic Inflammatory Response Syndrome (SIRS) Negative or Positive Colic Horses.

Colic horses show systemic inflammatory response syndrome (SIRS) clinical signs. Procalcitonin (PCT) showed increased circulating levels in sick horses. This study compares plasma PCT concentrations in healthy vs. SIRS negative/positive colic horses over time, and evaluates PCT and SIRS score potential correlation, to verify the usefulness of PCT for the evaluation of SIRS severity. Ninety-one horses were included; 43/91 were healthy, on basis of physical examination, blood work and SIRS score (score = 0), while 48/91 were sick colic horses, classified as SIRS-negative (score < 2) and positive (score ≥ 2). Moreover, a 0-6 point-scale SIRS score was calculated (assessing mucous membrane color and blood lactate concentration). PCT was evaluated at admission, and at 24, 48, 72 and 96 h, using a commercial kit for equine species. We verified by the ANOVA test PCT differences between healthy vs. colic horses, healthy vs. SIRS-negative or SIRS-positive colic horses, at all sampling times, and the correlation between the SIRS score at admission with the SIRS score. Statistically significant differences were detected between healthy vs. all colic horses and between healthy vs. SIRS-positive or negative horses at all sampling times. No correlation was observed between the SIRS score at admission and PCT values. PCT was statistically higher in colic horses compared to the healthy ones, suggesting a role as a biomarker for colic.

CO-oximetry measurements and antioxidant effects of ascorbic acid and methylene blue in equine methemoglobinemic blood.

OBJECTIVES: To determine the effects of time after sampling on CO-oximetry measurements of equine blood samples and the effects of adding ascorbic acid (AscAc) and methylene blue (MetBlue) to samples with methemoglobinemia. DESIGN: Experimental study. SETTING: University teaching hospital. ANIMALS: Thirty healthy adult horses assigned to 5 groups. INTERVENTIONS: Repeated CO-oximetry determinations were performed on venous (n = 6) and arterial blood samples (n = 7) stored at 0°C for 48 hours. Methemoglobinemia was induced in vitro in 17 additional blood samples. Six were used as untreated controls, 6 had AscAc added, and 5 had MetBlue added. Total hemoglobin, oxyhemoglobin, carboxyhemoglobin, methemoglobin (MetHb), and oxygen saturation of hemoglobin (SO2 ) were measured. MEASUREMENTS AND MAIN RESULTS: Oxyhemoglobin and SO2 increased from 69.8% ± 10.2% and 90% ± 3% to 82.8% ± 7.9% and 99% ± 3%, respectively, after 8 hours in venous blood (mean ± SD, P < 0.001). There was an effect of treatment (P = 0.032) and of time (interaction P = 0.003) on MetHb% in methemoglobinemic samples. The difference in absolute MetHb% from time 0 was as follows: 7.0% (interquartile range [IQR] = 21.2), -0.2% (IQR = 3.5), and -4.4% (IQR = 5.2) at 48 hours in control, AscAc, and MetBlue groups, respectively (P < 0.05). There was no effect of time on MetHb% in the AscAc group (23% [IQR = 52.6] at time 0 to 23.2% [IQR = 56.9] after 48 h). CONCLUSIONS: Storage of blood in ice water to determine O2 Hb and SO2 using a CO-oximeter should not exceed 4 hours. Measurement of MetHb% could be delayed by up to 48 hours if AscAc is added to the sample. MetBlue significantly decreased MetHb% over time. The limitations of this study include the fact that the antioxidant effects of AscAc and MetBlue were evaluated in vitro and not in vivo. Further studies are needed to evaluate different storage temperatures and syringe types.

TIM2 modulates retinal iron levels and is involved in blood-retinal barrier breakdown.

Careful control of iron availability in the retina is central to maintenance of iron homeostasis, as its imbalance is associated with oxidative stress and the progression of several retinopathies. Ferritin, known for its role in iron storage and detoxification, has also been proposed as an iron-transporter protein, through its binding to Scara5 and TIM2 membrane receptors. In this study, the presence and iron-related functions of TIM2 in the mouse retina were investigated. Our results revealed for the first time the presence of TIM2 receptors in the mouse retina, mainly in Müller cells. Experimental TIM2 downregulation in the mouse retina promoted, probably due to a compensatory mechanism, Scara5 overexpression that increased retinal ferritin uptake and induced iron overload. Consecutive reactive oxygen species (ROS) overproduction and vascular endothelial growth factor (VEGF) overexpression led to impaired paracellular and transcellular endothelial transport characterized by tight junction degradation and increased caveolae number. In consequence, blood-retinal barrier (BRB) breakdown and retinal edema were observed. Altogether, these results point to TIM2 as a new modulator of retinal iron homeostasis and as a potential target to counteract retinopathy.

Plasma iron concentrations and systemic inflammatory response syndrome in neonatal foals.

BACKGROUND: Sparse information regarding plasma iron concentration in neonatal foals and its utility as an inflammatory marker in this population has been published. OBJECTIVES: To determine the physiologic plasma iron concentration in neonatal foals. To assess its utility as an inflammatory marker to predict systemic inflammatory response syndrome (SIRS) and as a prognostic marker. ANIMALS: Forty-seven ill neonatal foals admitted to a referral equine hospital were divided in 2 groups based on the SIRS criteria (24 SIRS and 23 non-SIRS). Two control groups of 43 hospital and 135 stud farm healthy neonatal foals were also included. METHODS: Observational prospective study. Data were summarized by mean and its 95% confidence interval and absolute frequency and percentage for quantitative andqualitative variables. One-way ANOVA, ANCOVA (group and age effects) and Dunnett as posthoc analysis were used to compare plasma iron concentration among groups. RESULTS: Neonatal foals with SIRS did not have had any statistically significant different plasma iron concentrations compared to non-SIRS (P = .56) and stud farm control group (P = .99), 172.8 µg/dL (95% CI; 126.0-219.6), 193.1 µg/dL (139.1-247.2), and 181.8 µg/dL (171.3-192.4), respectively. Plasma iron concentration had a large variability in healthy neonatal foals, and was negatively correlated with age in hospital controls (rho = -0.387) and sick neonatal foals (rho = -0.598) (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma iron was not a useful marker of SIRS in neonatal foals and was not associated with outcome.

Temporary Relocation during Rest Periods: Relocation Stress and Other Factors Influence Hair Cortisol Concentrations in Horses.

Horse transportation for temporary relocation during rest periods is a common and widespread practice among horse owners, either from sport competition or working tasks. This study aimed to determine the effect of a relocation period and the multiple factors associated with a rest period on hair cortisol concentrations (HCCs) in horses. Additionally, this study reports the seasonal effect on HCCs and hair growth over a year. Thirteen police horses, Pure Spanish stallions of various ages (5-13 y), were selected to participate in this study. Hair sample collection was carried out approximately every 30 d for seven months (Study 1) and a year (Study 2). Cortisol determinations were performed by enzyme immunoassay. Interestingly, Study 1 revealed that relocated horses (n = 4) exhibited elevated HCCs compared with control horses (n = 4) after the relocation period (p < 0.05). Study 2 (n = 5) showed higher HCCs during summer compared with autumn and winter, and higher hair growth rates in winter compared with the other seasons (p < 0.05). Relocated horses had higher HCCs, suggesting a change in their welfare status, probably related to the sudden change in their surrounding conditions. However, these results should be interpreted cautiously due to the low sample size used. The nature of the relationship between HCCs and horse welfare needs to be further examined.

Prognostic value of measuring heart rate variability at the time of hospital admission in horses with colic.

OBJECTIVE: To evaluate the prognostic value of measuring heart rate variability (HRV) in horses with colic at the time of admission to a referral hospital. ANIMALS: 51 horses > 1 year of age with colic (41 that survived [survivors] and 10 that died or were euthanized [nonsurvivors]). PROCEDURES: HRV was recorded within 1 hour after admission by use of heart rate sensors with horses restrained in stocks. A 5-minute recording period was analyzed to obtain HRV measurements (eg, SD of R-R intervals [SDRR], root mean square of successive differences between R-R intervals [RMSSD], and geometric SDs determined from Poincaré plots [SD1 and SD2]). Variables associated with outcome (survival vs nonsurvival) were identified. Measurements were compared among diagnostic categories for colic (obstructive, inflammatory, or ischemic). RESULTS: SDRR and RMSSD were significantly higher in survivors (median [25th to 75th percentile], 91.0 milliseconds [78.9 to 114.6 milliseconds] and 64.8 milliseconds [40.9 to 78.4 milliseconds], respectively) than in nonsurvivors (50.7 milliseconds [29.1 to 69.2 milliseconds] and 33.4 milliseconds [12.6 to 47.9 milliseconds], respectively). Similarly, SD1 and SD2 were significantly higher in survivors (48.3 milliseconds [28.9 to 60.9 milliseconds] and 111.3 milliseconds [93.0 to 146.6 milliseconds], respectively) than in nonsurvivors (23.7 milliseconds [8.9 to 33.9 milliseconds] and 65.1 milliseconds [33.7 to 91.9 milliseconds], respectively). The SDRR and SD2 were significantly higher for horses with obstructive colic than for horses with ischemic colic. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of HRV in horses with colic may provide information on the underlying cause and be helpful in identifying horses less likely to survive.

Prevalence of exercise-induced pulmonary hemorrhage in competing endurance horses.

OBJECTIVE: To assess the prevalence of exercise-induced pulmonary hemorrhage (EIPH) among elite endurance horses after competition in a long-distance race. ANIMALS: 20 endurance horses and 12 nonexercised or minimally exercised age-, breed-, and trainer-matched horses from the same environment (control horses). PROCEDURES: Bronchoalveolar lavage fluid samples collected from endurance horses at 3 to 8 days (sample A) and 36 to 38 days (sample B) after the race (100 km in 1 day [n = 3], 70 km/d for 2 days [12], or 100 km/d for 2 days [5]) were cytologically examined for the presence of hemosiderophages. Samples from control horses were collected at the same time as sample B was obtained from respective matched endurance horses and similarly examined. Horses with bronchoalveolar lavage fluid samples in which > 1% of identified cells were hemosiderophages were considered to have evidence of EIPH. RESULTS: Of 20 endurance horses, 9 (45%; 95% confidence interval, 25% to 66%) and 10 (50%; 95% confidence interval, 29% to 71%) had cytologic evidence of EIPH in samples A and B, respectively. Evidence of EIPH was present in 6 of 20 (30%) horses at both sample collection times, 3 (15%) at the first sample time only, and 4 (20%) at the second sample time only. In contrast, 1 of 12 control horses had cytologic evidence of EIPH. CONCLUSIONS AND CLINICAL RELEVANCE: The prevalence of EIPH in these elite endurance horses (45% to 50%) was higher than previously reported estimates for poor-performing endurance horses; however, differences in criteria for identification of EIPH should be considered when comparing findings between studies.

Ophthalmologic findings associated with Rhodococcus equi bronchopneumonia in foals.

OBJECTIVE: To describe ocular findings associated with Rhodococcus equi bronchopneumonia in foals, and to determine whether severity of the ocular lesions is related with outcome. ANIMALS STUDIED: Foals diagnosed with R equi infection at the VTH-UAB from January 2002 to December 2017. PROCEDURE: Rhodococcus equi infection was diagnosed by means of clinical signs, radiographic/ultrasonographic findings, and/or positive culture. In all the foals, a complete ophthalmic examination by a boarded ophthalmologist was performed and ocular signs were recorded and graded (0-4). RESULTS: Thirty-nine foals were included in the study, from which 12 showed signs of bilateral anterior uveitis (30.8%). Among these, three foals were classified as mildly uveitis-affected (MUA:7.7%) and nine as severely uveitis-affected (SUA:23.1%). Five SUA foals showed green aqueous flare (5/9;55.5%). Despite the systemic treatment, 9/39 sick foals died (23.1%), the fatality rate being different between groups: SUA (4/9;44.4%), MUA (0/3; 0%) and nonuveitis-affected foals (5/27;18.5%). Among SUA foals, only one with green aqueous flare died (1/5;20%). CONCLUSION: Bilateral anterior uveitis is highly prevalent in foals with R equi pneumonia (30.8%). The severity of anterior uveitis might be considered a nonsurvival prognostic factor and, until proven otherwise, green aqueous flare could be taken as a strongly suggestive ocular sign of the disease. Findings of this study remark the clinical relevance of performing a complete ophthalmic examination in sick foals, in order to help in the diagnosis and prognosis of uveal diseases, as well as to guaranteeing visual soundness.

Investigation of ventricular pre-excitation electrocardiographic pattern in two horses: clinical presentation and potential causes.

Two horses referred to the Unitat Equina, Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, for unrelated clinical problems, and with no previous history of cardiac disease exhibited an intermittent ventricular pre-excitation electrocardiographic pattern during hospitalization. Both animals showed decreased plasma total and ionized magnesium concentrations, but no other relevant electrolyte disturbances were detected. Altered interventricular septal motion associated with ventricular pre-excitation beats (VPBs) was detected on M-mode echocardiography in both horses. The likely localization of an accessory pathway (AP) was identified in case 2 using pulsed-wave tissue Doppler imaging in the left anterior paraseptal location. Decreased frequency of the VPB was observed with long-term magnesium supplementation and restoration of plasma magnesium concentrations. The presence of ventricular pre-excitation electrocardiographic pattern was attributed to higher sensitivity of the AP to hypomagnesemia in both cases.