Pathomorphological study on gastroduodenal ulceration in horses: localisation of lesions

Gastroduodenal ulceration is a prevalent disease in foals and adult horses. Decreased performance as well as fatal complications relate to this syndrome. The objective of our study was to determine the prevalence of gastric ulceration in a mixed population of horses by postmortem examination and to evaluate a possible association between equine gastric ulcer syndrome (EGUS) and sex or age of the examined horses, to evaluate the localisation of lesions in the proximal part of the gastrointestinal tract and to determine the occurrence of gastric parasites. Postmortem examinations were performed on 71 horses over a period of 24 months. Gastric ulcers were found in 52 horses (73.2%). There was no significant association between age or sex and occurrence of gastric ulcers. In all horses the squamous mucosa lesions were localised near the margo plicatus (100% of the cases), whereas in 23 horses the lesions were near the margo plicatus and lesser curvature and in 7 horses at the greater curvature. In 18 horses the mucosa was affected in the whole extent of the margo plicatus and in 1 horse diffuse lesions of the squamous mucosa were noted. Lesions of the glandular mucosa were localised in 11 horses at the fundic area, in 1 horse they occurred in the pylorus, and in 10 horses diffuse lesions of the glandular mucosa were recorded. A low prevalence of Gasterophilus intestinalis infection was detected (1 horse, 1.4%). We have confirmed that gastric ulcers are a common problem in horses and duodenal or oesophageal ulceration is rare (not a single case of the latter was found in this study). Lesions in the glandular mucosa of the stomach are more frequent in suckling foals than in older animals. Lesions of the glandular mucosa are also common in adult horses, and a complete gastroscopic examination including examination of the pylorus is advisable to evaluate this syndrome.     

Associations between age or sex and prevalence of gastric ulceration in Standardbred racehorses in training

OBJECTIVE: To determine associations between age, sex, or medical treatment and prevalence and severity of gastric ulceration in Standardbred racehorses in training. DESIGN: Cross-sectional study. ANIMALS: 224 Standardbred racehorses in training. PROCEDURE: Gastroscopy was performed on each horse, and mucosal ulceration was graded from 0 (normal mucosa, no lesions) to 3 (extensive, often coalescing, lesions with areas of deep ulceration). Associations between age, sex, or treatment and prevalence and severity of ulcers were evaluated. RESULTS: Prevalence of gastric ulceration was 87%. Although there was little association between age and prevalence of ulcers, there was an association between age and severity of ulcers. Most 2-year-old horses (57.7%) had an ulcer score of 0 or 1. In all other age groups, most (58% to 82.61%) of horses had an ulcer score of 2 or 3. Although overall prevalence of ulceration was comparable among sex groups, the relative risk for gastric ulceration increased with age in castrated males, whereas it decreased in females and sexually intact males. CONCLUSIONS AND CLINICAL RELEVANCE: Gastric ulceration is common in Standardbred horses in race training. Severity is higher in horses > or = 3 years of age than in 2-year-old horses. Relative risk for ulceration increases with age in castrated males.     

The Influence of Stable Management and Feeding Practices on the Abnormal Behaviors Among Stabled Horses in Malaysia

The present study aimed to provide preliminary data on the prevalence of oral stereotypic, locomotory stereotypic, and redirected behaviors as well as their associations with stable management and feeding practices. In this cross-sectional study, a total of 207 working horses used for leisure riding, equestrian sport, polo, endurance, and patrolling were selected from seven equine facilities. Data on the stable management and feeding practices were obtained through the stable records, interviews, and on-site monitoring visits, whereas the prevalence of abnormal behaviors in the studied population was determined using the instantaneous scan sampling method. Most horses in the present study worked for more than 8 hours per week (n = 93). In addition, more horses were fed three times per day (n = 65) with different amounts of hay, concentrate, and chaff. Among the study population, oral stereotypic behaviors had the highest prevalence (n = 281; 54%), followed by redirected behavior (n = 181; 34%), and locomotory stereotypic behaviors had the lowest prevalence (n = 63; 12%). The oral stereotypic behavior was found to be significantly influenced (P < .05) by the working hours, amount of hay, and amount of concentrate. Both locomotory stereotypic and redirected behaviors were found to be influenced (P < .05) by the number of feedings per day and the amount of hay. In summary, the present study has proven that the stable management and feeding practices could influence the prevalence of different abnormal behaviors in the majority of working horses, with oral stereotypy being the most common abnormal behavior in this country.     

Postmortem findings of gastric ulcers in Swedish horses older than age one year: a retrospective study of 3715 horses (1924-1996)

The present study was performed to estimate retrospectively the prevalence of gastric ulceration in necropsied Swedish horses and to evaluate some potential risk factors. Horses (n = 3715) older than age one year and necropsied 1924-1996 were included. Information about breed, gender, age, season of death, clinical signs of colic, Gasterophilus larvae and documentation of diseases in different organs was recorded. Data on size, number and anatomical distribution of gastric ulcers were also obtained. The cold-blooded horses and the Standardbreds were the 2 most dominating breeds in our material. Gastric ulcers/erosions were seen in 633 (17%) of the horses. The highest prevalence was found in Thoroughbreds (19%) and Standardbreds (19%), whereas only 7% of the cold-blooded horses were affected. The cutaneous region along the margo plicatus was the most commonly affected area (52%). Multiple ulcers were seen in 62% of the horses with gastric ulcers and concurrent ulcers in the oesophagus were reported in 6%. In the bivariate analysis, significant associations were found between gastric ulcers and signs of colic (P<0.001) and gender (P<0.001), as well as between concomitant bowel (P<0.001), liver (P<0.05) and oesophageal (P<0.01) lesions. Using a multivariate logistic regression model, only year of necropsy and breed were found significantly to influence the risk of gastric ulceration by decreasing the Log Likelihood test value. The present study shows clearly that gastric ulceration has been present in Swedish horses throughout the 20th century, which also may be the situation worldwide.     

Prevalence of gastric ulcer syndrome in high-level endurance horses

Reasons for performing the study: Equine gastric ulcers syndrome (EGUS) prevalence studies are rare in the endurance horse and none has been carried out to date in horses competing at high level. Objectives: To determine the prevalence of EGUS in high‐level endurance horses. Methods: Thirty endurance horses competing at high level were selected and submitted to 2 gastroscopic examinations. The first gastroscopy was performed during the interseason period, and the second during the competition season within 2–3 days following a ride of 90–160 km. Data related to housing, feeding, training system as well as age, breed and gender were recorded for each horse. Results: The prevalence of squamous gastric ulcers was 48% during the interseason period (mean score 0.85 ± 0.13 on a scale from 0–4) and 93% during the competition season (mean score 1.60 ± 1.15) with a highly significant difference between the seasons (P = 0.001). Most of the lesions were situated in the squamous portion of the stomach but 33.3% of horses showed also glandular lesions. Significant influence of training and performance level on the gastric score (according to the distance of the ride preceding the second gastroscopy) was shown (P = 0.038). There was also a significant influence of housing on the gastric score (P = 0.002) showing higher scores in the horses kept totally on pasture (mean score: 2.14 ± 0.14) vs. horses housed in a mixed environment (stable + pasture, mean score: 1.43 ± 0.17). Both the pastured and (stabled + pastured) groups were receiving a grain supplement but the pastured group received a higher daily starch intake, which might explain the higher ulcer prevalence. There was no influence of age, breed or gender on the gastric scores. Conclusions: The high prevalence of gastric lesions observed in this study is probably related to the high level of training and performance of the horses examined compared to the population of horses included in the prior study. Potential relevance: This prevalence of EGUS in high‐level endurance horses is comparable to the prevalence established in racing horses. The equine veterinarians may take into consideration EGUS as a potential cause of poor performance.     

Prevalence of gastric ulceration in Swedish Standardbreds in race training

REASONS FOR PERFORMING STUDY: There is little information about the prevalence of gastric ulcers in Standardbred trotters and potential correlations between ulcers and various traits, e.g. age, sex, performance, temperament and feeding regimens, need further elucidation. OBJECTIVES: The prevalence of ulcers in the gastric squamous mucosa of Swedish Standardbreds was estimated and the associations between ulcer score and age, sex, performance, temperament and feeding regimens were determined. METHODS: Eighty Swedish Standardbreds in active race training, trained by 9 different trainers, underwent gastroscopy. Information on age, gender, status of training, performance over the last 4 months compared with the trainer's expectations before that period, behaviour, eating habits, feed type, bedding type, time spent outdoors per day and medical treatment during the last month was collected. Gastroscopy was performed and lesions in the squamous gastric mucosa were scored from 0 to 4 (0 = no lesions; 4 = > 5 lesions with haemorrhage, > 10 lesions with no haemorrhage, or a large area of diffuse loss of surface epithelium). RESULTS: Twenty-four (30%) of the horses had no lesions in the squamous mucosa, 22 (27.5%) had a score of 1; 21 (26.2%) score 2; 9 (11.2%) score 3; and 4 (5%) score 4. Horses that were in preparatory training and those that had raced during the last month were significantly more affected than horses that were fit for racing but had not raced during the last month, using a logistic regression model with trainer incorporated as a random effect. CONCLUSIONS: The study confirmed a high prevalence of ulcers in the gastric squamous mucosa of Standardbreds in race training. Of the studied parameters only status of training showed a significant association with gastric ulcers of the squamous mucosa. POTENTIAL RELEVANCE: Gastric ulceration is a common disease and diagnosis should be made by endoscopic examination of the gastric mucosa, since parameters such as age, gender, performance, behaviour, eating habits provide only weak clues as to which horses might be affected. Further studies are needed to determine the aetiology of the syndrome and to find ways to reduce, if possible, the frequency of gastric ulcers.     

Gastric ulcers in standardbred racehorses: prevalence,lesion description,and risk factors

This study was performed to estimate the prevalence of gastric ulcers in Standardbred racehorses, to describe the lesion score and location, and to identify potential risk factors. Two hundred seventy-five (275) Standardbred horses from 5 training centers and 2 racetracks in Quebec, Canada, were studied. Historical data for the 2 months before examination were recorded for each horse, and the presence of gastric ulcers was determined by gastroscopy. A previously reported scoring system that used grades 0-3 for gastric lesions was used. Overall, 121 horses (44.0%; 95% CI, 38.1-50.1%) had gastric ulcers. The prevalence of gastric ulcers was significantly higher (P < .0001) in actively racing horses (63.3%; 95% CI, 54.7-71.2%) than in horses at rest. Multivariate analysis defined that horses in racing (OR = 9.29; 95% CI, 3.55-24.3) were significantly more likely to have gastric ulcers than horses at rest and that trotters (OR = 2.23; 95% CI, 1.28-3.86) were more likely to have gastric ulcers than pacers. The number of lesion sites (P < .0001) and poor body condition (P < .0001) were significantly associated with lesion scores. Gastric ulcers are highly prevalent in Standardbred racehorses. Furthermore, actively racing horses and trotters are more likely to have gastric ulcers. Also, poor body condition in Standardbred racehorses may be an indication that gastric ulcers are present and that lesion scores are high. The cause-and-effect relationship between poor body condition and the presence of gastric ulcers is unclear.     

Chronic obstructive pulmonary disease (COPD): factors influencing the occurrence.

Breed, age, weight, type of work performed, seasonal onset, poor ventilation and exposure to moulds in the habitat were investigated in relation to the occurrence of chronic obstructive pulmonary disease (COPD). COPD was most commonly detected in showjumping and hacking horses. The older a horse, the more likely it was to become affected although most were 6 to 10 years of age. Of the horses in this sample of the population, which was not a random one, thoroughbred horses were affected least and ponies most often. The high incidence in ponies was related to their more frequent exposure to poor quality fodder and bedding. Most horses are exposed to the hazard of moulds, but more affected horses were so exposed than those not affected with COPD. Poor ventilation of the stable increased the chance of a horse becoming affected. Sex, body weight and season of onset of coughing had no influence on the occurrence of the disease.     

Study of laryngopharyngeal pathology in Thoroughbred horses in southern California

Reasons for performing study: There is increasing anecdotal evidence among horse owners, trainers and equine clinicians of a high prevalence of subepiglottic ulcers, suggested to have a negative effect on racing performance. Objectives: To provide a prevalence study and pathological characterisation of laryngopharyngeal lesions with emphasis in the subepiglottic area and, in particular, subepiglottic ulcers. Methods: The study was carried out on 91 Thoroughbred racehorses received for post mortem examination from 4 major Southern California racetracks. The most common reason for submission was catastrophic musculoskeletal injury, but others include sudden death, laminitis, colic, colitis, neurological disorders, pleuropneumonia and arytenoid chondropathy. Laryngopharyngeal specimens were collected and examined grossly; selected cases were also examined histopathologically. Results: Thirteen horses (14.3%) had at least one type of laryngopharyngeal abnormality, 7 horses (7.7%) had lesions in the subepiglottic soft tissues, including 4 subepiglottic ulcers, 2 soft palate ‘kissing lesions' and one 'subepiglottic scar’. Eight horses (8.8%) had lesions elsewhere in the laryngopharynx, including mucosal ulcerations, arytenoid chondropathy, epiglottic entrapment and partial absence of arytenoid cartilage. Conclusions and potential relevance: Lesions in the subepiglottic area were among the most prevalent in this study, suggesting that an important percentage of laryngopharyngeal abnormalities may be missed during routine endoscopy of the standing horse, which often does not include the examination of subepiglottic tissues. Pathologically, subepiglottic ulcers were chronic‐active with viable hyperplastic epithelial margins, suggesting that proper healing and re‐epithelialisation should occur with appropriate treatment. In most cases, the lesions observed do not necessarily indicate a clinical problem and more extensive prevalence studies and correlation between abnormalities found and performance are needed to assess the clinical relevance of subepiglottic soft tissue lesions accurately.     

Risk factors associated with equine gastric ulceration syndrome (EGUS) in 201 horses in Denmark

Reasons for performing study: The prevalence (up to 93% in Thoroughbred racehorses) and severity of equine gastric ulceration syndrome (EGUS) has been associated with type of training and differing management practices. However, there have been few studies to confirm these findings in nonracehorses in Europe. Objectives: To investigate the prevalence of EGUS in a population of Danish horses, during winter when the horses had been housed and fed for at least 8 weeks and to analyse the influence of feed, work level and environment on the risk of EGUS of §grade 2 in severity. Methods: A total of 201 horses, not in active race‐training, were evaluated, representing 23 different stables from all 5 regions within Denmark. All horses were considered to be healthy and not on medical treatment for EGUS. Endoscopically observed ulcer lesion scores were based on the number present (0–4) and severity (0–5). Univariate and multivariable mixed effects logistic regression models were developed using EGUS score as the dependent variable. An ulceration severity score of §2 was regarded as being clinically significant. Separate models were developed for horses with ulcers in either the glandular or nonglandular regions of the stomach graded §2 (EGUS §2) and for those horses that had nonglandular ulcers graded §2 (NG §2). Results: In this population, 53% (107/201) of horses were graded as having EGUS §2 with 95 (47%) horses having NG §2. Three variables were significantly (P<0.05) associated with EGUS §2: straw being the only forage available; exceeding 2 g/kg bwt of starch intake/day or §1 g/kg bwt/meal; and water not being available in the turn out paddock. Risk of NG §2 significantly increased when straw was the only forage available, 1 g/kg bwt of starch/meal was exceeded, water was not available in the turnout paddock and the interval between forage feeding was <6 h. Conclusion and potential relevance: This study has confirmed that components of the diet, readily modifiable, may have an important impact on the risk of EGUS in the nonracehorse. Differences in the multivariable models produced for all ulcers and nonglandular ulcers support differences in the aetiology of ulcers in different locations of the stomach.     

The prevalence of oral ulceration in Swedish horses when ridden with bit and bridle and when unridden

Oral soft tissue ulcers are common disorders of horses, but it is unclear if their prevalence is increased by riding horses with a bit and bridle. Oral examinations were performed on 113 horses and ponies, all which had received routine dental floating, that were divided into four groups depending on when they had last been ridden with a bit and bridle. The subjects comprised: group 1, a randomly selected population of ridden horses; group 2, a group of horses examined after being rested at pasture for 5 weeks; group 3, the previous group following 7 weeks of riding with a bit and bridle, and group 4, brood mares that had not been ridden for at least 11 months. Lip and intraoral soft tissue lesions were recorded at seven pre-determined locations, with lesions classified as large or small; acute or chronic.The examinations showed that horses that were currently being ridden with a bit and bridle had a significantly higher prevalence of large and acute buccal ulcers opposite the maxillary Triadan 06 teeth and of the commissures of the lips, as compared to horses that were not being currently ridden. It was concluded that using a bit and bridle can cause oral ulceration even in horses that have regular prophylactic dental floating. It is suggested that riding tack should be individually fitted for each horse and also that prophylactic dental treatments should be individually adapted for each horse.     

Prevalence of Ocular Disorders in an Indian Population of Horses

The objective of this clinical study was to report the prevalence of ocular disorders in a large population of horses from the Indian army. Both eyes of 500 horses were examined using a direct ophthalmoscope and by a transillumination procedure. Intraocular pressures were measured in several study horses. Fluorescein dye, Schirmer tear test, and menace testing were performed when indicated. Corneal culture swabs were collected from horses affected with corneal ulcers found on ophthalmoscopic examination. A total of 100 horses were found to be affected with some form of ocular disorder. The eye problems recorded were congenital eye lid disorders (2%) and included a subcutaneous cyst in the lower eye lid and slit in upper eye lid; conjunctivitis (12%); chronic interstitial keratitis (30%); a parasite in the anterior chamber (1%), which was however not removed for genus and species identification; phthisis bulbi (1%); uveitis (24%); glaucoma (13%); cataracts (3%); unilateral retinal hemorrhage (1%); luxation of cataractous lens (3%); posterior synechia (2%); and corneal ulceration (8%). Pseudomonas spp was the most common bacteria identified in horses affected with corneal ulceration. Vision-threatening ocular disorders are high in Indian army horses; this is a cause of major concern for the rider and the horse and, therefore, it is important to include ocular examination in horses as part of a routine and complete physical examination.     

Airway inflammation in Michigan pleasure horses: prevalence and risk factors

REASONS FOR PERFORMING STUDY: Although subclinical airway inflammation is thought to be common in horses, there is little information on its prevalence and none on risk factors. OBJECTIVE: To determine the prevalence and risk factors for an increased number of inflammatory cells and for mucus accumulation in the trachea of pleasure horses. METHODS: Horses (n = 266) in stables (n = 21) in Michigan were examined endoscopically, once in winter and once in summer 2004. Visible tracheal mucoid secretions were graded 0-5 and inflammatory cell numbers counted in a tracheal lavage sample. Information collected about each horse included age, gender, presence of cough, percent time indoors and source of roughage. The repeated measures were analysed by generalised estimating equations and linear mixed models. RESULTS: Horses eating hay, especially from round bales, had the most neutrophils, whereas horses feeding from pasture had the fewest. Being female and being outdoors in winter were associated with increased numbers of inflammatory cells. Older horses had fewer macrophages than young horses. More than 70% of horses had >20% neutrophils in tracheal lavage. Twenty percent of horses had a mucus accumulation score >1; 17% had both a mucus score >1 and >20% neutrophils. The significant risk factors for mucus accumulation >1 were age >15 years, feeding on hay as compared to pasture, and being outdoors for more than 80% time in winter. Even though mucus accumulation score >1 was a risk factor for cough, only half of such horses coughed. Cough and mucus accumulation were associated with increased number of neutrophils. CONCLUSIONS: In comparison to pasture feeding, hay feeding, particularly from round bales, was associated with an increased number of neutrophils in the airway. Being outdoors in winter was associated with increased numbers of inflammatory cells and with mucus accumulation. Because 70% of horses have >20% neutrophils, this value should not be used as the sole indicator of airway inflammation. POTENTIAL RELEVANCE: The study reinforces the importance of hay feeding and older age as risk factors for inflammatory airway disease. Horses that do not have 'heaves' may be best kept indoors when winters are cold.     

The prevalence and anatomical distribution of equine gastric ulceration syndrome (EGUS) in 201 horses in Denmark

Reasons for performing study: The prevalence (up to 93% in Thoroughbred racehorses) and severity of equine gastric ulceration syndrome (EGUS) have been correlated with the type of training and associated management practices. However, there have been few reports to confirm these findings in nonracehorses in Europe. Objectives: To describe the prevalence, anatomical distribution, severity and number of gastric ulceration lesions in a population of Danish pleasure horses; and to investigate differences for groups based on age, breed type and workload. Methods: A total of 201 horses not in active race‐training, age 7 months‐27 years, were evaluated, representing 23 different stables from all 5 regions of Denmark. These horses were considered to be healthy by the owner and not on veterinary treatment for EGUS. Endoscopically observed ulcer lesion scores were based on the number present (0–4) and severity (0–5). The presence or absence of ulcers in the glandular and/or nonglandular regions of the stomach was recorded and which site the most severe ulcers were found. Results: The prevalence of EGUS severity score ≥2 was 53%. The most severe lesions were commonly observed at the margo plicatus. Although older horses were not more likely to be affected by clinically significant EGUS they were more likely to have lesions in both the glandular and nonglandular regions. Differences in location of EGUS lesions were identified in different age groups, breed types and in horses exposed to different levels of work. Conclusion and potential relevance: This study confirms that gastric ulceration can be prevalent in a group of apparently clinically normal horses, not in intensive work. Further investigation of reasons for differences in EGUS location between different populations may aid toward the development of novel preventive measures.     

Investigation of the prevalence of summer eczema in Icelandic horses in northern Germany

An epidemiological study on summer eczema (SE) was performed in 490 Icelandic horses from 24 stud farms located in Lower Saxony and Westphalia. The study revealed a prevalence of summer eczema of 29.8 %. Horses imported from Iceland were affected with a frequency of 71.9 %, whereas horses born in Germany and other countries had a prevalence of 15.6 % and 27.3 %. Mares (33.1 %) and geldings (29.1 %) were more often affected by summer eczema than stallions with 15.5 %. The most common sites of summer eczema were mane and tail. Five to eight years old horses were more severely affected by SE than younger or older horses. Piebald horses showed higher degrees of SE than grey horses. The high prevalence of SE in Icelandic horses kept in Germany was due to imported horses from Iceland particularly horses imported at an age of seven to 15 years were at an extremely high risk to SE (96.4 %). The prevalence of SE significantly increased with higher age. Chestnut and grey horses born in Germany were prone to a lower risk to SE than bay, black or piebald horses. In horses imported from Iceland, a higher inbreeding coefficient was significantly related to a lower prevalence of SE. The most efficient measure recommended for reduction of SE in Germany would be to abandon imports of Icelandic horse from Iceland.     

Effects of environmental control on pulmonary function of horses affected with chronic obstructive pulmonary disease

The effects of environmental control on horses affected with chronic obstructive pulmonary disease was assessed by clinical examination and pulmonary function tests, ie, maximum change in intrathoracic pressure, tidal volume, minute volume, non-elastic work of breathing, dynamic compliance, inspiratory and expiratory flow rates and arterial blood gas analysis. A controlled environment (ie, bedding horses on shredded paper and feeding a complete cubed diet) caused symptomatic COPD affected horses to become asymptomatic within four to 24 days (mean ± sd 8.4 ± 4.8 days). When asymptomatic, their pulmonary function values did not differ significantly from those of normal horses, which indicates that the pathophysiological changes occurring in equine COPD are reversible. The time taken for horses to become asymptomatic correlated significantly with age, duration of illness and severity of disease as adjudged by the non-elastic work of breathing.     

Endoscopic findings of the stomach in pleasure horses in Poland

Background

This study was performed to determine the prevalence of ulcers in the gastric squamous and glandular mucosa in Polish pleasure horses.

Study design

Medical records from gastroscopic examinations of 108 pleasure horses of different breeds were reviewed. The study population consisted of two groups; group I (n = 48) with horses that expressed mild clinical signs of gastric ulcer syndrome (EGUS) including poor appetite, slight weight loss or poor body condition, and group II (n = 60) with horses that had no signs of gastrointestinal problems. The age range was 4–10 years, including 5 males, 34 castrated males (geldings) and 69 mares. The prevalence, distribution and severity of gastric ulcers were recorded. Lesions involving the squamous mucosa and the glandular mucosa of the antrum and pylorus were graded and compared between groups.

Results

Significant difference was found in the presence and severity of gastric ulcers between the two groups of horses. The overall prevalence of gastric ulcers in the first group of horses (n = 48) was 59% while in the group of clinically healthy horses (n = 60) the prevalence of gastric lesion was 40% (P = 0.004). Almost 19% of horses from group I had between 6–10 lesions (EGUS score III) and nearly 19% had either >10 localized lesions or very large diffuse lesions (EGUS number score IV). The number of ulcerations in affected horses were significantly lower in group II compared to group I (P = 0.016) as 10% of horses had 6–10 lesions (EGUS number score III) and nearly 14% had either >10 localized lesions or very large diffuse lesions (EGUS number score IV). Gastroscopy revealed that nearly 32% of horses from the second group had an ulceration EGUS score ≥ II.

Discussion and conclusions

This study confirms that gastric ulcerations can be prevalent in apparently clinically normal pleasure horses and a complete gastroscopic examination including the examination of the pylorus is advisable to evaluate this syndrome.     

Post-mortem findings of gastric ulcers in Swedish horses up to one year of age: a retrospective study 1924-1996

Necropsy records from 702 horses, less than one year old, that were subjected to necropsy between 1924 and 1996 were used to estimate the prevalence of gastric ulceration in younger horses and to evaluate some potential risk factors that may contribute to the development of gastric ulceration. Information concerning breed, gender, age, season of death, clinical signs of colic, medical treatment, parasitism and documentation of diseases in different organs were recorded, as well as size, number and anatomical distribution of ulcers. Gastric ulcers were found in 96 of 702 young horses (14%) and gastritis in another 64 animals (9%). The cutaneous region adjacent to margo plicatus (51%), and the corpus region were commonly affected (46%). The investigation clearly demonstrates that gastric ulceration has affected young Swedish horses to a similar degree during most of the 20th century. A significant (p < or = 0.05) association between gastric ulcers and the signs of colic, parasitism and a concomitant intestinal, liver, and oesophageal involvement was found. No breed or sex predilection with gastric ulcers was obtained. The risk of gastric ulcers was highest during the fall (odds ratio 3.52) and lowest during the summer (odds ratio 0.45). The seasonal variation could not be explained by concomitant findings of Gasterophilus larvae. By using a multivariate logistic regression analysis, only season significantly influenced the risk of gastric ulceration.     

Chronic obstructive pulmonary disease: Usefulness of clinical signs, bronchoalveolar lavage, and lung biopsy as diagnostic and prognostic aids

We examined 18 horses with clinical signs of chronic obstructive pulmonary disease (COPD) using physical examination, cytological and bacteriological evaluation of bronchoalveolar fluid, and percutaneous lung biopsy. In 16 cases, histological examination of lung tissue confirmed the diagnosis of COPD. Two horses were excluded: one had uncomplicated bacterial pneumonia and in the other a satisfactory lung biopsy could not be obtained. In horses with COPD, the most common historical complaint was coughing, which was reported in 88%. The most frequently detected abnormal finding on physical examination was abnormal lung sounds; these were detected in 69% of horses at rest and in 88% of horses breathing deeply into a bag. A novel finding was that 29% of horses had lung sounds that were quieter than would be expected for the degree of respiratory effort. Horses with COPD had increased percentages of neutrophils and decreased percentages of lymphocytes and macrophages in their bronchoalveolar lavage fluid. Bronchiolar neutrophil infiltration and peribronchiolar mast cell accumulation in lung biopsy tissue had the highest correlation with clinical condition. The severity of pathological changes in biopsies of lung did not predict whether the horse would die in the two to four year follow-up period. Horses that died in the follow-up period were more severely affected clinically at initial presentation than horses that were alive at the end of the follow-up period.