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Equine asthma is considered a non-infectious respiratory disease characterized by inflammation and hypersensitivity. Given the importance of antimicrobial stewardship, an international survey was designed to investigate the use of antimicrobials in asthmatic horses and the factors influencing prescription behavior. An online survey was distributed in six languages by international mailing lists and social media from December 2020 to January 2022. Of the 434 responses recorded, 249 veterinarians working in 25 countries finished the survey. These included 79 ECEIM/ACVIM diplomats. A total of 204 respondents confirmed national regulations concerning antimicrobial use in their country. Knowledge of the asthma definitions as presented in the revised ACVIM consensus statement was greater in veterinarians treating over 95% of equine patients compared to veterinarians treating more species, based on 10 questions (answers consistent with the consensus statement in 7 (IQR 5-9) and 4 (IQR 3-6) questions, respectively, ( p < 0.001)). A total of 131 respondents stated to use antimicrobials (at least 'sometimes') in at least one of the three presented cases consistent with equine asthma. Trimethoprim-Sulfa combinations, penicillin(s), and tetracyclines were prescribed most (by 105, 53 and 38 veterinarians, respectively). Aminoglycosides, cephalosporins and fluoroquinolones were also selected (22, 15, 9 veterinarians respectively). Tetracyclines and cephalosporins are prescribed more often by veterinarians working without national regulations ( p 0.019 and p 0.035, respectively). The most selected factors influencing prescription behavior were: 'tracheal wash culture' (62% of 131 veterinarians using antimicrobials in these cases), 'whether other horses in the barn have similar complaints' (60%), and 'response to other forms of therapy' (53%). In conclusion, insight into prescription behavior is the first step towards minimizing and optimizing antimicrobial use.

Equine bronchoalveolar lavage (BAL) is usually performed with 250-500 mL of isotonic saline at pH 5.5. The acidic pH of saline may cause an increase in airway neutrophil count 48 h after BAL. Other isotonic solutions such as Ringer's solution, phosphate-buffered saline (PBS) or Plasma-Lyte 148 ® have a neutral pH of 7.4 and might be a better choice for BAL by not provoking inflammation and the influx of neutrophils into airways. BAL was performed in four healthy horses in four different lung lobes using four different solutions in a randomized crossover design. In each lobe, BAL was performed twice with a 48 h interval using 250 mL of solution. Automated total nucleated cell counts (TNCs) were recorded, and differential cell counts in lavage fluid were determined by two investigators blinded to treatments. The mean volume of BAL fluid retrieved was 51 ± 14%. The mean neutrophil percentage (%N) increased from 1.5 ± 0.9% to 14.7 ± 9.6% at 48 h ( p < 0.001) but was not significantly affected by the solution used or the lung lobe sampled. In conclusion, in this study, the influx of neutrophils into airways after BAL was independent of the type of isotonic solution used and the lung lobe sampled. Saline remains an appropriate solution for BAL in horses.

Exercise and physical training are known to affect gastrointestinal function and digestibility in horses and can lead to inaccurate estimates of nutrient and energy digestibility when markers are used. The effect of exercise on apparent nutrient digestibility and faecal recoveries of ADL and TiO2 was studied in six Welsh pony geldings subjected to either a low- (LI) or high-intensity (HI) exercise regime according to a cross-over design. Ponies performing LI exercise were walked once per day for 45 min in a horse walker (5 km/h) for 47 consecutive days. Ponies submitted to HI exercise were gradually trained for the same 47 days according a standardized protocol. Throughout the experiment, the ponies received a fixed level of feed and the daily rations consisted of 4.7 kg DM of grass hay and 0.95 kg DM of concentrate. The diet was supplemented with minerals, vitamins and TiO2 (3.0 g Ti/day). Total tract digestibility of DM, organic matter (OM), CP, crude fat, NDF, ADF, starch, sugar and energy was determined with the total faeces collection (TFC) method. In addition, DM and OM digestibility was estimated using internal ADL and the externally supplemented Ti as markers. Urine was collected on the final 2 days of each experimental period. Exercise did not affect apparent digestibility of CP, crude fat, starch and sugar. Digestibility of DM (DMD), OM (OMD), ADF and NDF tended to be lower and DE was decreased when ponies received the HI exercise regime. For all treatments combined, mean faecal recoveries of ADL and Ti were 87.8±1.7% and 99.3±1.7%, respectively. Ti was not detected in the urine, indicating that intestinal integrity was maintained with exercise. Dry matter digestibility estimated with the TFC, ADL and Ti for ponies subjected to LI exercise were 66.3%, 60.3% and 64.8%, respectively, while DMD for HI ponies were 64.2%, 60.3% and 65.2%, respectively. In conclusion, physical exercise has an influence on the GE digestibility of the feed in ponies provided with equivalent levels of feed intake. In addition, the two markers used for estimating apparent DMD and OMD indicate that externally supplemented Ti is a suitable marker to determine digestibility of nutrients in horses performing exercise unlike dietary ADL.

Background: Organic dust is associated with Equine asthma. Ionization should reduce airborne dust levels., Objectives: To determine the effect of ionization of air, type of bedding, and feed on the levels of airborne dust, endotoxin, and fungal colonies in horse stables., Animals: 24 healthy University-owned horses occupied the stables., Methods: A randomized controlled cross-over study. Four units with 6 stables were equipped with an ionization installation (25 VA, 5000 Volt Direct Current). Horses were kept either on wood shavings and fed haylage (2 units), or on straw and fed dry hay (2 units). Measurements were performed with and without activated ionization, during daytime and nighttime, repeatedly over the course of a week and repeatedly during 4-6 weeks. Statistical analysis was performed using a mixed effect model with Akaike's Information Criterion for model reduction and 95% profile (log) likelihood confidence intervals (CI)., Results: Ionization did not alter concentrations of dust, endotoxin, or fungi, fewer. In the units with straw and hay, the concentration of dust, endotoxin, and fungi (difference in logarithmic mean 1.92 (95%CI 1.71-2.12); 2.86 (95%CI 2.59-3.14); 1.75 (95%CI 1.13-2.36)) were significantly higher compared to wood shavings and haylage., Conclusions and Clinical Importance: The installation of a negative air-ionizer in the horse stable did not reduce concentrations of dust, endotoxin, and viable fungal spores. The substantial effect of low dust bedding and feed is confirmed., (Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

Background: Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees., Hypothesis/objectives: To measure hypoglycin A in the most common maple tree species in the Netherlands, and to determine whether concentration of toxin is a predictor of AM in horses., Methods: A total of 278 samples of maple tree leaves, sprouts, and seeds were classified by species. Mean concentrations of hypoglycin A were compared for the type of sample, the season and the occurrence of AM in the pasture (non-AM versus AM). Statistical analysis was performed using generalized a linear model (SPPS22)., Results: Almost all Acer pseudoplatanus samples contained hypoglycin A, with concentrations differing significantly among sources (P < .001). Concentrations were significantly higher in seeds from the AM group than in seeds from the non-AM group (856 ± 677 and 456 ± 358 mg/kg, respectively; P = .039). In sprouts and leaves this was not the case. Acer platanoides and Acer campestre samples did not contain detectable concentrations of hypoglycin A., Conclusions and Clinical Importance: Acer platanoides and campestre seem to be safe around paddocks and pastures, whereas almost all Acer pseudoplatanus samples contained hypoglycin A. In all AM cases, Acer pseudoplatanus was found. Despite significantly higher concentration of hypoglycin A in seeds of pastures where AM has occurred, individual prediction of AM cannot be made by measuring these concentrations because of the high standard deviation., (Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

Background: Insulin resistance in horses is an emerging field of interest as it is thought to be a contributing factor in the pathogenesis of many equine conditions., Objectives: The objectives of the present study were to determine the effects of long-term oral administration of L-carnitine on insulin sensitivity, glucose disposal, plasma leptin concentrations and acylcarnitine spectrum both in plasma and urine., Animals and Methods: Six 3-year-old healthy warmblood geldings were used. In a double blind 2 × 2 Latin square design at a dosage of 100 mg/kg body weight (BW)/day for 28 days the effects of oral supplementation of L-carnitine (as fumarate) were assessed. Glucose disposal and insulin sensitivity were measured by means of the euglycemic-hyperinsulinemic clamp technique. Radioimmunoassays were used to determine plasma leptin and insulin concentrations. Electrospray tandem mass spectrometry was used to assess acylcarnitines both in plasma and urine. Statistical analysis was performed using a linear mixed-effects model and P values <0.05 were considered significant., Results: Long-term L-carnitine administration did not affect insulin sensitivity. Plasma leptin and free carnitine concentrations in plasma and urine increased significantly (P = 0.047 and 0.000, respectively) following L-carnitine administration as well as short-chain acylcarnitines in plasma and urinary excretion of short- and medium-chain acylcarnitines., Conclusion and Clinical Relevance: Given the effects of oral administration of L-carnitine further clinical study is necessary in order to assess the potential beneficial effects in equine patients suffering from metabolic myopathies such as acquired multiple acyl-CoA dehydrogenase deficiency., Impact for Human Medicine: The current study supports the treatment rationale of short-chain acyl-CoA dehydrogenase deficiency in humans with L-carnitine at an oral dosage of 100 mg/kg BW/day.

Reasons for Performing Study: Appropriate management of atypical myopathy (AM) requires the establishment of an accurate diagnosis and prognosis. Furthermore, preventive measures to avoid AM need to be refined., Objectives: The aims of the study were as follows: 1) to improve the diagnosis of AM; 2) to identify prognostic predictors; and 3) to refine recommended preventive measures based on indicators of risk factors., Methods: An exploratory analysis of cases in Europe between 2006 and 2009 reported to the Atypical Myopathy Alert Group was conducted. Based on clinical data, reported cases were allocated into 2 groups: confirmed or highly probable AM (AM group; further divided into survivors and nonsurvivors); and cases with a low probability of having AM or with another final diagnosis (non-AM group). Using Welch's test and odds ratios corrected for multiple comparisons, the AM vs. non-AM groups were compared to identify indicators for diagnosis and risk factors, and survivors vs. nonsurvivors in the AM group were compared to identify prognostic factors. Sensitivity, specificity and positive and negative predictive values were calculated for specific clinical signs related to final diagnosis and outcome., Results: From 600 reported cases, 354 AM cases (survival rate of 26%) and 69 non-AM cases were identified, while there were insufficient data to categorise the remainder. Variables valuable for diagnosing AM compared with similar diseases were as follows: presence of dead leaves and wood and/or trees on pastures; sloping pastures; full-time pasture access; no food supplementation; normal body condition; pigmenturia; normothermia; and congested mucous membranes. Nonsurvival was associated with recumbency, sweating, anorexia, dyspnoea, tachypnoea and/or tachycardia. Survival was associated with remaining standing most of the time, normothermia, normal mucous membranes, defaecation and vitamin and antioxidant therapy., Conclusions and Potential Relevance: This study refines the list of risk factors for AM. Clinical signs valuable for diagnosis and prognosis have been identified, enabling clinicians to improve management of AM cases., (© 2012 EVJ Ltd.)

Reasons for Performing Study: Improved understanding of the epidemiology of atypical myopathy (AM) will help to define the environmental factors that permit or support the causal agent(s) to exert toxicity., Objectives: This European survey of AM aimed to describe spatiotemporal distribution, survival, clinical signs, circumstances in which AM develops and its different expressions between countries and over time., Methods: The spatiotemporal distribution, history and clinical features of AM cases reported to the Atypical Myopathy Alert Group from 2006 to 2009 were described. Comparisons of data from the most severely affected countries and from the large outbreaks were made with Fisher's exact and Welch's tests with Bonferroni correction., Results: Of 600 suspected cases, 354 met the diagnostic criteria for confirmed or highly probable AM. The largest outbreaks occurred during the autumns of 2006 and 2009 in Belgium, France and Germany. For the first time, donkeys, zebras and old horses were affected, and clinical signs such as gastrointestinal impaction, diarrhoea, penile prolapse, buccal ulceration and renal dysfunction were observed. Affected horses spent >6 h/day on pastures that almost always contained or were surrounded by trees. The latency period was estimated at up to 4 days. Overall survival rate was 26%. Although differences between countries in affected breeds, body condition, horse management and pasture characteristics were recognised, the common presenting clinical signs and mortality were similar between countries., Conclusions and Potential Relevance: This study describes new data on case details, history and clinical course of AM that is of preventive, diagnostic and therapeutic value. However, the true impact of the findings of this study on the development of or severity of AM should be tested with case-control studies., (© 2012 EVJ Ltd.)

This article reviews the literature on equine atypical myopathy (AM), an acute, severe rhabdomyolysis that occurs in horses at pasture. The prevalence, mortality, clinical signs, pathology, potential aetiology, typical aspects, diagnosis, treatment, and prognosis are described. Horse management, characteristic weather conditions, and possible preventive measures are also discussed. In addition, the characteristics of 54 highly probable or confirmed cases of equine AM occurring between autumn 2009 (27 cases) and spring 2010 (27 cases) in the Netherlands are described. Of the 54 affected horses, nineteen were mares, eleven geldings, and eight stallions; the sex of the other sixteen horses was not recorded. The mortality rate (74.5%) was in the same range as that reported in earlier studies. Many cases were reported at about the same time. Thirty-five horses had been pastured near maple trees, and in fifteen cases the maple trees were known to be infected with the fungus Rhytisma acerinum.

Earlier research on ten horses suffering from the frequently fatal disorder atypical myopathy showed that MADD (multiple acyl-CoA dehydrogenase deficiency) is the biochemical derangement behind atypical myopathy. From five horses that died as a result of this disease and seven healthy control horses, urine and plasma were collected ante mortem and muscle biopsies were obtained immediately post-mortem (2 patients and 7 control horses), to analyse creatine, purine and carbohydrate metabolism as well as oxidative phosphorylation. In patients, the mean creatine concentration in urine was increased 17-fold and the concentration of uric acid approximately 4-fold, compared to controls. The highest degree of depletion of glycogen was observed in the patient with the most severe myopathy clinically. In this patient, glycolysis was more active than in the other patients and controls, which may explain this depletion. One patient demonstrated very low phosphoglycerate mutase (PGAM) activity, less than 10% of reference values. Most respiratory chain complex activity in patients was 20-30% lower than in control horses, complex II activity was 42% lower than normal, and one patient had severely decrease ATP-synthase activity, more than 60% lower than in control horses. General markers for myopathic damage are creatine kinase (CK) and lactic acid in plasma, and creatine and uric acid in urine. To obtain more information about the cause of the myopathy analysis of carbohydrate, lipid and protein metabolism as well as oxidative phosphorylation is advised. This study expands the diagnostic possibilities of equine myopathies., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The objective of this study is to assess the influence of acute exercise, training and intensified training on the plasma amino acid profile. In a 32-week longitudinal study using 10 Standardbred horses, training was divided into four phases, including a phase of intensified training for five horses. At the end of each phase, a standardized exercise test, SET, was performed. Plasma amino acid concentrations before and after each SET were measured. Training significantly reduced mean plasma aspartic acid concentration, whereas exercise significantly increased the plasma concentrations of alanine, taurine, methionine, leucine, tyrosine and phenylalanine and reduced the plasma concentrations of glycine, ornithine, glutamine, citrulline and serine. Normally and intensified trained horses differed not significantly. It is concluded that amino acids should not be regarded as limiting training performance in Standardbreds except for aspartic acid which is the most likely candidate for supplementation., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Reasons for Performing Study: The quantity of glucose disposal during exercise (walk and trot) compared to rest by use of the hyperglycaemic clamp technique has not been reported previously and has relevance to nutritional requirements., Hypothesis: Exercise (walk and trot) significantly increases glucose disposal compared to rest., Methods: Seven healthy Dutch Warmblood mares, all in dioestrus, mean ± s.d. age 11.6 ± 2.4 years and weighing 569 ± 40 kg were fasted for 12 h prior to a hyperglycaemic clamp at rest (maintaining a steady state of the blood glucose concentration during 30 min), walk (10 min, 1.5 m/s), trot (20 min, 4.4 m/s), walk (10 min, 1.5 m/s) and rest again (maintaining a steady state during 30 min). Plasma glucose concentrations were measured every 5 min. The mean rate of glucose disposal was calculated by corrections for glucose loss via the glucose space and urine. A one-way ANOVA with post hoc Bonferroni was performed., Results: The mean ± s.d. rate of glucose disposal was 15.0 ± 2.1 at first rest, 25.1 ± 6.2 at first walk, 37.4 ± 9.1 at trot, 33.0 ± 13.1 at second walk and 18.7 ± 4.6 µmol/kg bwt/min at second rest. Values at trot and at second walk differed significantly from values at first rest, whereas values at both rests were similar as well as at first rest and at first walk., Conclusions: Mean rate of glucose disposal of Warmblood horses increased 2.5 times during trot compared to basal., Potential Relevance: The hyperglycaemic clamp technique is an attractive nonisotope method to assess the rate of glucose disposal in exercising horses., (© 2010 EVJ Ltd.)

This case-series describes fourteen horses suspected of equine acquired multiple acyl-CoA dehydrogenase deficiency (MADD) also known as atypical myopathy of which seven cases were confirmed biochemically with all horses having had access to leaves of the Maple tree (Acer pseudoplatanus) covered with European tar spot (Rhytisma acerinum). Assessment of organic acids, glycine conjugates, and acylcarnitines in urine was regarded as gold standard in the biochemical diagnosis of equine acquired multiple acyl-CoA dehydrogenase deficiency., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Objective: To evaluate alterations in skeletal muscle carnitine metabolism during exercise and training by measuring changes in plasma acylcarnitine concentrations in Standardbreds., Animals: 10 Standardbred geldings with a mean +/- SD age of 20 +/- 2 months and weight of 384 +/- 42 kg., Procedures: In a 32-week longitudinal study, training on a treadmill was divided into 4 phases as follows: phase 1, acclimatization for 4 weeks; phase 2, 18 weeks with alternating endurance and high-intensity exercise training; phase 3, increased training volume and intensity for another 6 weeks; and phase 4, deconditioning for 4 weeks. In phase 3, horses were randomly assigned to 2 groups as follows: control horses (which continued training at the same level as in phase 2) and high-intensity exercise trained horses. At the end of each phase, a standardized exercise test (SET) was performed. Plasma acylcarnitine, fatty acids, and lactic acid and serum beta-hydroxybutyric acid (BHBA) concentrations were assessed before and at different time points after each SET., Results: Plasma lactic acid, total nonesterified fatty acids, 3-hydroxyisobutyric acid, and acetylcarnitine (C2-carnitine) concentrations significantly increased during SETs, whereas serum BHBA, plasma propionylcarnitine (C3-carnitine), and plasma butyryl- and isobutyrylcarnitine (C4-carnitine) concentrations decreased significantly, compared with those before SETs., Conclusions and Clinical Relevance: Our findings indicated that the plasma acylcarnitine profile in horses likely reflects skeletal muscle carnitine metabolism following exercise, thereby providing a possible practical method to investigate potential disorders in carnitine metabolism in horses with myopathy.

The aim of the current study was to assess lipid metabolism in horses with atypical myopathy. Urine samples from 10 cases were subjected to analysis of organic acids, glycine conjugates, and acylcarnitines revealing increased mean excretion of lactic acid, ethylmalonic acid, 2-methylsuccinic acid, butyrylglycine, (iso)valerylglycine, hexanoylglycine, free carnitine, C2-, C3-, C4-, C5-, C6-, C8-, C8:1-, C10:1-, and C10:2-carnitine as compared with 15 control horses (12 healthy and three with acute myopathy due to other causes). Analysis of plasma revealed similar results for these predominantly short-chain acylcarnitines. Furthermore, measurement of dehydrogenase activities in lateral vastus muscle from one horse with atypical myopathy indeed showed deficiencies of short-chain acyl-CoA dehydrogenase (0.66 as compared with 2.27 and 2.48 in two controls), medium-chain acyl-CoA dehydrogenase (0.36 as compared with 4.31 and 4.82 in two controls) and isovaleryl-CoA dehydrogenase (0.74 as compared with 1.43 and 1.61 nmol min(-1) mg(-1) in two controls). A deficiency of several mitochondrial dehydrogenases that utilize flavin adenine dinucleotide as cofactor including the acyl-CoA dehydrogenases of fatty acid beta-oxidation, and enzymes that degrade the CoA-esters of glutaric acid, isovaleric acid, 2-methylbutyric acid, isobutyric acid, and sarcosine was suspected in 10 out of 10 cases as the possible etiology for a highly fatal and prevalent toxic equine muscle disease similar to the combined metabolic derangements seen in human multiple acyl-CoA dehydrogenase deficiency also known as glutaric acidemia type II.

Two horses (a 7-year-old Groninger warmblood gelding and a six-month-old Trakehner mare) with pathologically confirmed rhabdomyolysis were diagnosed as suffering from multiple acyl-CoA dehydrogenase deficiency (MADD). This disorder has not been recognised in animals before. Clinical signs of both horses were a stiff, insecure gait, myoglobinuria, and finally recumbency. Urine, plasma, and muscle tissues were investigated. Analysis of plasma showed hyperglycemia, lactic acidemia, increased activity of muscle enzymes (ASAT, LDH, CK), and impaired kidney function (increased urea and creatinine). The most remarkable findings of organic acids in urine of both horses were increased lactic acid, ethylmalonic acid (EMA), 2-methylsuccinic acid, butyrylglycine (iso)valerylglycine, and hexanoylglycine. EMA was also increased in plasma of both animals. Furthermore, the profile of acylcarnitines in plasma from both animals showed a substantial elevation of C4-, C5-, C6-, C8-, and C5-DC-carnitine. Concentrations of acylcarnitines in urine of both animals revealed increased excretions of C2-, C3-, C4-, C5-, C6-, C5-OH-, C8-, C10:1-, C10-, and C5-DC-carnitine. In addition, concentrations of free carnitine were also increased. Quantitative biochemical measurement of enzyme activities in muscle tissue showed deficiencies of short-chain acyl-CoA dehydrogenase (SCAD), medium-chain acyl-CoA dehydrogenase (MCAD), and isovaleryl-CoA dehydrogenase (IVD) also indicating MADD. Histology revealed extensive rhabdomyolysis with microvesicular lipidosis predominantly in type 1 muscle fibers and mitochondrial damage. However, the ETF and ETF-QO activities were within normal limits indicating the metabolic disorder to be acquired rather than inherited. To our knowledge, these are the first cases of biochemical MADD reported in equine medicine.

Over the last ten years a fatal syndrome associated with immunodeficiency and severe anaemia has been reported in young Fell pony foals in the UK. Affected foals are usually normal at birth but from the age of 2-4 weeks they progressively lose condition and become severely anaemic. Signs of immunodeficiency become apparent at around 3-4 weeks of age. Morbidity is low but mortality is 100% despite intensive treatment. Affected foals die or are euthanized usually before they reach the age of 3 months. A single autosomal recessive gene is suggested to be on the basis of the syndrome. Recently, affected Fell pony foals have been identified in the Netherlands and between June 2003 and August 2005, six affected Fell pony foals were referred to the Faculty of Veterinary Medicine for investigation.

Objective: To determine whether treatment of horses with antitussive agents before bronchoalveolar lavage (BAL) reduces the frequency and intensity of the cough reflex during BAL., Animals: 8 healthy horses., Procedure: Standard BAL was performed on each horse weekly for 6 weeks. Detomidine was used as a general sedative, and various antitussive agents were evaluated for their suitability to suppress undesirable coughing. Treatments administered prior to BAL consisted of saline (0.9% NaCl) solution (control treatment), codeine, butorphanol tartrate, glycopyrrolate, lidocaine hydrochloride (final concentration, 0.33%), and lidocaine hydrochloride at a final concentration of 0.66% (lidocaine 0.66%). Frequency and intensity of coughing were digitally recorded throughout the BAL procedure. The volume of BAL fluid collected was measured, and the fluid was cytologically examined to assess potential effects of the medications on composition., Results: Coughing frequency was significantly reduced after intratracheal administration of lidocaine 0.66%. Moreover, intratracheal administration of lidocaine 0.66% or IV administration of butorphanol resulted in a significant reduction in the intensity of coughing episodes. All other treatments failed to significantly suppress coughing frequency and intensity, compared with results for the saline treatment. Glycopyrrolate caused obvious adverse clinical effects. Treatments did not influence the volume of BAL fluid collected nor composition of the fluid., Conclusions and Clinical Relevance: Intratracheal administration of lidocaine (final concentration, 0.66%) proved to be the most reliable method to reduce frequency and intensity of coughing in horses during BAL.

Healthy horses received aerosolised, intranasal or oral doses of 3 mg of fluticasone propionate evenly divided over morning and evening treatments for seven days. The bioavailability of the drug was determined in terms of the suppression of the endogenous cortisol concentrations in the horses during the period of treatment. The horses which received the aerosolised drug had significantly lower concentrations of endogenous cortisol on days 5 and 8 than the horses which received aerosolised placebo. The horses which received nasal and oral doses of fluticasone propionate showed no significant changes in their endogenous cortisol concentrations.

Since the only registrated anti-ectoparasiticum for horses (foxim) is no longer available in The Netherlands, some cases of amitraz intoxication of the horse have occurred. In this article the literature concerning amitraz intoxications and experiments will be discussed and some cases will be described.

Mares regularly have an enlarged ovary. The main causes are haematomas, anovulatory follicles, abscesses, and neoplasia. The granulosa-theca-cell tumour is by far the most common neoplasia of the ovary (about 97%) and accounts for 2.5% of all equine tumours. In this article the differential diagnosis of an enlarged ovary and the background of granulosa-theca cell tumours are reviewed. A case is described of a mare with a very large granulosa-theca cell tumour in the left ovary, which was discovered 1 month after delivery of a healthy foal. This case is special not only because the tumour was enormous (diameter 60 cm) but also because the contralateral ovary was functional and there were no behavioural changes. The fact that a haematoma had been found 2 years earlier made the diagnosis even more difficult.