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It is generally accepted that besides cortisol concentrations, parameters of heart rate variability (HRV) are appropriate indicators of stress in horses. The aim of this study was to determine anticipatory stress in eight Standardbred stallions participating in harness race. Cortisol and HRV responses to a mild exercise performed in training circumstances were compared to a maximal effort exercise performed in real trotting race conditions. Parameters of HRV reflecting vagal (root mean square of the successive differences, RMSSD) and sympathetic nervous system activity (ratio of the low and high frequency component, LF/HF) were recorded before warming up (baseline) and during exercise. Plasma cortisol concentrations were obtained for the following stages of the exercise: before warming up (baseline), after warming up, after the exercise has finished and after a 30-min recovery. Baseline LF/HF ratio was higher before the race compared to the pre-training values (12.0 ± 6.6 vs. 5.9 ± 4.5, P = 0.009), while RMSSD did not show such difference (34.8 ± 15.9 ms vs. 48.0 ± 30.5 ms, P = 0.96). Cortisol level was higher in the case of race for all samples compared to training (P = 0.012). There were no significant differences between plasma cortisol levels obtained for the subsequent stages of race. Horses in the present study showed anticipatory response before race as shown by differences in pre-training (97.3 ± 16.4 nmol/L) and pre-race cortisol levels (171.8 ± 18.7 nmol/L), respectively (P0.001). Pre-race HRV only partly confirmed this phenomenon.

Any factors that increase negative pressure in the upper respiratory tract (URT) can influence its mechanics. The aim of this report was to describe the results of URT diagnostic evaluation with overground endoscopy in sport and pleasure horses. The URT and plasma lactate levels were evaluated during rest and during overground endoscopic examination in 19 cases. Horses performed their normal training session. When history and clinical examination suggested a lower airway obstruction, we performed bronchoalveolar lavage. Dorsal displacement of the soft palate (DDSP) was diagnosed in 8 of 19 horses, which might have developed secondary to URT or lower respiratory tract inflammation or obstruction. DDSP was also detected at rest in four cases. Laryngeal hemiplegia (LHP) was diagnosed in 15 of 19 horses, 11 of which were complex cases with other types of URT obstructions. Severe pharyngeal collapse (PHC), suspected already at rest, was visible in two cases during exercise. In contrast, PHC diagnosed with nasal occlusion at rest in two cases was fully compensated under the rider. Plasma lactate levels significantly decreased during exercise. All DDSP cases were suspected to be of inflammatory or obstructive origin, which is different from findings in racehorses, where extrinsic causes are more common. Resting endoscopic examinations were sensitive in cases of obstructive origin. LHP and PHC could not be predicted on the basis of findings at rest, and increased neuromuscular activity during exercise could compensate for the problem in less severe cases. Decreased levels of lactate could be explained by the increased clearance during exercise.

A 9-year-old Shagya Arabian pregnant mare showing signs of acute colic, underwent exploratory laparotomy at our clinic. Owing to the discovery of an inoperable leiomyoma in the abdominal cavity, the animal was euthanized. The 305-day-old fetus, which showed signs of prematurity was removed by Caesarean section and resuscitated. Clinicopathologic examination revealed a low neutrophil:lymphocyte ratio. Radiographic evaluation of the carpus and tarsus was performed and showed grade 3 ossification according to the Adams-Poulos Grading System. The immature gastrointestinal tract was unable to digest enteral feeding; this led to the development of enterocolitis and septicemia. Thrombophlebitis developed at the site of the long-acting intravenous catheter and methicillin-resistant Staphylococcus aureus was isolated from the exudate. The guttural pouches were empyematous. Follow-up radiographic examinations indicated improvement in bone maturation. The foal was discharged in a good state of health 35 days postnatum, and apart from an easily managed respiratory tract infection, no further problems were reported.

Temperament has not been taken into account in previous studies evaluating the stress response to exercise in horses. The aim of the present study was to investigate the cortisol response in Thoroughbred racehorses to a single exercise bout, and to analyse the results based on the basic personality of the horse examined. Twenty healthy Thoroughbred horses were selected for the study based on a 25-item rating questionnaire survey used for characterising equine temperament. Eight temperamental and twelve calm horses took part in the experiment. The horses trotted as a warm-up activity, and then galloped on a rounded sand track. Blood sampling was conducted four times for each horse. Horses with a more excitable temperament showed a higher cortisol response to the test (P = 0.036). In conclusion, cortisol levels in response to a mild intensive exercise can be affected by temperament in horses. Serum cortisol may be a relevant marker to quantify individual temperamental differences in racehorses.

An 8-year-old Hungarian warmblood gelding used for show jumping was evaluated because of poor performance and chronic weight loss. On admission, oral and gastroesophageal ulcerations and malabsorption were detected. Results of thoracic radiography, ultrasonography, bronchoalveolar lavage cytology, and positive polymerase chain reaction for equine herpesvirus 5 raised the possible diagnosis of equine multinodular pulmonary fibrosis. However, abdominal ultrasonography revealed inhomogeneous spleen with many different sized well-demarcated hypoechoic areas, which suggested further differential diagnoses such as tuberculosis, neoplasias, immune mediated diseases, systemic granulomatous disease (SGD), or toxicoses. The horse was euthanized at the owner's request because of the poor condition and possible grave prognosis. Histopathology findings were characteristic of SGD, which is a rare disorder of horses characterized by skin lesions, weight loss, and granulomatous inflammation of multiple organ systems. The lack of skin lesions in this case is an unusual finding. Systemic granulomatous disease is hypothesized to be induced by multiple conventional antigens that are not cleared from affected tissues. Equine herpesvirus 5 might have triggered the granulomatous reactions in this particular case.