bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiopulmonary changes associated with abdominal insufflation of carbon dioxide in mechanically ventilated, dorsally recumbent, halothane anaesthetised horses
Authors: DONALDSON LYDIA L. , TROSTLE S. S. , WHITE N. A. 
Published: April 2010

SummaryThe use of laparoscopy for the diagnosis or therapeutic management of abdominal disease in the horse has distinct advantages when it allows the horse to remain standing. However, distending the abdomen by insufflation of a biologically active gas in an anaesthetised horse may add to the physiological challenge of general anaesthesia and recumbency. The cardiopulmonary responses to abdominal insufflation with carbon dioxide (CO2) to 15 mmHg pressure were evaluated in 6 horses in dorsal recumbency anaesthetised with halothane in oxygen and subjected to laparoscopic colopexy. Vaporiser settings targeted a fractional expired halothane of 1.5 MAC and a clinically acceptable depth of anaesthesia. Pressure and rate controlled positive pressure ventilation was adjusted to an ETCO2of 35 mmHg before abdominal insufflation and was not changed thereafter. Cardiopulmonary data were collected before, at 30 and 60 min during and 30 min after CO2insufflation. ANOVA for repeated measures followed by Tukey's protectedttest were used to determine differences. Partial pressure of oxygen and pH of arterial blood, tidal volume and systemic vascular resistance decreased during abdominal insufflation and laparoscopic surgery whereas mean arterial blood pressure, right atrial pressure, cardiac index, stroke index, partial pressure of CO2in arterial blood and end tidal respiratory gases, and calculated physiological shunt increased significantly. Only systemic vascular resistance returned to the pre‐insufflation level after de‐sufflation. The hypercapnia, acidosis and apparent increase in cardiac work that accompany CO2pneumoperitoneum for laparoscopic surgery could place the anaesthetised horse at additional risk of perioperative complications.
Effects of inhaled beclomethasone dipropionate on respiratory function in horses with chronic obstructive pulmonary disease (COPD)
Authors: AMMANN V. J. , VRINS A. A. , LAVOIE J.‐P. 
Published: April 2010

SummaryThe effects of beclomethasone dipropionate on pulmonary function and arterial blood gas values were investigated in horses with chronic obstructive pulmonary disease (COPD). Six mature mares, diagnosed as having COPD based on clinical signs, cytological examination of bronchoalveolar lavage and pulmonary function testing, were used. Beclomethasone dipropionate (3750 μg) was administered b.i.d. for a 2 week period with a metered dose inhaler using a mask. Pulmonary function tests and arterial blood gas analyses were performed at weekly intervals, starting before beclomethasone administration and for 4 weeks thereafter. Upper airway endoscopy and nasopharyngeal fungal cultures were performed before and after treatment.Maximal variations in transpulmonary pressure (ΔPL) were elevated in all horses at baseline. Beclomethasone administration resulted in a significant decrease in ΔPL, in 5 horses, and ΔPL, fell to within the normal range in 4 horses. Two weeks after the end of treatment, ΔPL. was at or above baseline values in all horses. Total pulmonary resistance and elastance decreased significantly during treatment and returned to or above baseline values after the administration of beclomethasone was discontinued. At baseline, PaO2range was 53–90 mmHg. In 4 horses with pronounced laboured breathing, PaO2increased with treatment. One horse became reluctant to inhale the beclomethasone after one week, and only a transient improvement in respiratory function was noted in this animal. One horse developed a mild lower airway infection 24 h after the beginning of treatment, but no other possible side effects were noticed. Pharyngeal fungal cultures were negative before and after treatment.It can be concluded from the results of this study that inhaled beclomethasone dipropionate causes a marked improvement of respiratory function in horses with COPD.
Reconstruction of the jugular vein in horses with post thrombophlebitis stenosis using saphenous vein graft
Authors: RIJKENHUIZEN A. B. M. , VAN SWIETEN H. A. 
Published: April 2010

SummaryA surgical technique is described in which a saphenous vein graft is used to reconstruct the jugular vein in horses with facial oedema due to post thrombophlebitic stenosis of the jugular vein. The saphenous vein was harvested from the contralateral limb and implanted in the occluded vein by 2 side‐to‐end anastomoses. Intra‐ and post operatively anticoagulative medication was administered. In 2 out of 3 patients the reconstruction resulted in a permanent patent graft and resolution of the facial oedema. In one patient the graft thrombosed.
Fluid administration attenuates the haemodynamic effect of frusemide in running horses
Authors: HINCHCLIFF K. W. , MCKEEVER K. H. 
Published: April 2010

SummaryThe effect of blood volume repletion after frusemide administration on the right atrial and pulmonary artery pressure responses of horses to exercise has not been reported. We examined right atrial and pulmonary artery pressure and plasma atrial natriuretic peptide concentration (ANP) responses to an incremental exercise test in 6 Standardbred mares. Horses were treated, in a 3 way cross over design, with isotonic saline, frusemide (1 mg/kg bwt, i.v.), and frusemide followed 3 h later by lactated Ringer's solution (12 ml/kg bwt, i.v.). Three and a half hours after saline or frusemide administration the horses completed a standard exercise test. Frusemide significantly affected the right atrial and pulmonary artery pressure and ANP responses to exercise. Fluid administration decreased plasma total protein concentrations at rest and during running and abolished the effects of frusemide on the haemodynamic and ANP responses to exercise. These results suggest that the haemodynamic effect of frusemide in running horses is mediated, in large part, by a reduction in plasma and blood volume.
Electromyographic activity of the long digital extensor muscle in the exercising Thoroughbred horse
Authors: CHEUNG T. K. , WARREN L. K. , LAWRENCE L. M. , THOMPSON K. N. 
Published: April 2010

SummarySurface electrodes were used to record electromyographic (EMG) activity of the long digital extensor muscle on the right hindlimb of 8 Thoroughbred horses for 8 s at the walk and 8 s at the trot before (unfatigued) and after (fatigued) an exercise test. The exercise test was performed on a motorised treadmill set on a 10% grade. Each test started at a speed of 6 m/s which was increased by 1 m/s each minute until the horse fatigued as indicated by its inability to keep pace with the treadmill with minimal encouragement. Observations were made on the horses prior to conditioning (untrained state) and after 8 weeks of regular exercise (trained state). The mean root‐mean‐square (rms) values of EMG bursts collected in each experimental trial were determined for each horse and group means were derived from the mean of independent subjects. Statistical comparisons for differences in rmsEMG were related to gait, fatigue and training. Mean rmsEMG at the trot was consistently higher than at the walk (P<0.05). At the walk, mean fatigued rmsEMG tended to be higher than the mean unfatigued rmsEMG in the untrained state and was significantly higher in the trained state (P<0.05). At the trot, mean fatigued rmsEMG was higher (P<0.05) than mean unfatigued rmsEMG in both the untrained and trained states. Training did not have an effect on mean rmsEMG of unfatigued muscles at the walk or the trot (P>0.05). However, fatigued muscles experienced higher EMG activity in the trained state at the walk (P<0.05). A similar tendency was observed at the trot. Results of this study suggest that surface EMG measurement may be useful for evaluating fatigue in exercising horses.
Post traumatic keratouveitis in horses
Authors: MOORE C. P. , HALENDA RUTH M. , GREVAN VICKIE L. R. , COLLINS B. K. 
Published: April 2010

SummaryTraumatic keratouveitis in horses is characterised by a unilateral, aseptic, vascularising keratitis accompanied by moderate to severe anterior uveitis. In a series of 9 cases of post traumatic keratouveitis, topical and systemic nonsteroidal drugs and atropine were used to control the anterior uveitis while allowing spontaneous corneal healing. Among the 9 cases reported, 6 affected eyes previously treated with local corticosteroids took significantly longer to resolve when compared to 3 eyes in which corticosteroids had not been administered. It was concluded that, in cases of equine post traumatic keratouveitis, locally administered corticosteroids inhibit healing of damaged corneal stroma and, by prolonging the keratitis, perpetuate the concurrent anterior uveitis.
Stress fractures of the vertebral lamina and pelvis in Thoroughbred racehorses
Authors: HAUSSLER K. K. , STOVER SUSAN M. 
Published: April 2010

SummaryThirty‐six Thoroughbred racehorses that died at California racetracks between October 1993 and July 1994 were evaluated for stress fractures in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. The lumbosacral spine and pelvis were collected, debrided of soft tissues and examined visually for the presence of an incomplete fracture line and focal periosteal proliferation, characteristic of a stress fracture.Sixty‐one per cent of specimens had evidence of stress fracture in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. Vertebral lamina stress fractures were found in 50% of specimens and were positively associated with the severity of dorsal spinous process impingement and overall severity of articular process degenerative changes. Pelvic stress fractures affected 28% of specimens and occurred more frequently in older horses. Pelvic stress fractures were positively associated with the severity of lumbar transverse process impingement and several ilial articular surface degenerative changes.A high prevalence of vertebral and pelvic stress fractures was noted in this sample of Thoroughbred racehorses that died because of unrelated injuries. Vertebral and pelvic stress fractures need to be considered in the clinical evaluation of horses with back problems or hindlimb lameness. Undiagnosed stress fractures of the vertebrae or pelvis could be a significant cause of poor performance and lameness in Thoroughbred racehorses.
Net joint moments and powers in the equine forelimb during the stance phase of the trot
Authors: CLAYTON HILARY M. , LANOVAZ J. L. , SCHAMHARDT H. C. , WILLEMEN M. A. , COLBORNE G. R. 
Published: April 2010

SummaryThe objective of this study was to provide normative data describing the net joint moments and joint powers for the stance phase of the forelimb in trotting horses. Kinematic and force plate data, synchronised in time and space, were collected for the right forelimb of 6 Warmblood horses moving at a trot. The 3‐D kinematic data were collapsed onto a sagittal plane, and were combined with the vertical and longitudinal ground reaction forces and with segment morphometric data to calculate net joint moments in the sagittal plane across the distal interphalangeal (coffin), metacarpophalangeal (fetlock), carpal, elbow and shoulder joints. The joint mechanical power was calculated as the product of the joint moment and the joint's angular velocity. Major peaks on the moment and power curves were identified.Each joint showed consistent and repeatable patterns in the net joint moments and joint powers. During most of stance the net joint moment was on the caudal/palmar side of all joints except the shoulder. At the coffin joint the power profile indicated an energy absorbing function that peaked at 74% stance, which coincided with the maximal longitudinal propulsive force. The fetlock joint behaved as an elastic spring; energy was absorbed in the first half of stance as the flexor tendons and SL stored elastic energy, which was released in the second half of stance as a result of elastic recoil. The carpus did not appear to play an important role in energy absorption or propulsion. Both the elbow and shoulder joints showed what appeared to be phases of elastic energy storage and release in the middle part of the stance phase, followed by a propulsive function at the shoulder in the later part of stance. The fetlock, carpus and elbow showed virtually no net generation or absorption of energy. The net energy generation at the shoulder joint was approximately equal to the energy absorption at the coffin joint.In human subjects specific gait pathologies produce characteristic alterations in the shape of the power profile as well as changes in the amount of energy absorbed and generated at the joints. In horses evaluation of net joint moments and joint powers will further our understanding of the mechanics and energetics of lameness, and may prove to be a useful diagnostic tool. An understanding of the function and dysfunction of different anatomical structures will facilitate the interpretation of clinical findings in terms of mechanical deficits.
Maintenance of anaesthesia with sevoflurane and oxygen in mechanically‐ventilated horses subjected to exploratory laparotomy treated with intra‐ and post operative anaesthetic adjuncts
Authors: CARROLL GWENDOLYN L. , HOOPER R. N. , RAINS C. B. , MARTINEZ ELIZABETH A. , MATTHEWS NORA S. , HARTSFIELD SANDEE M. , BELEAU M. H. 
Published: April 2010

SummaryEight healthy horses premedicated with xylazine and induced with ketamine were used to evaluate sevoflurane in oxygen for maintenance of anaesthesia during elective exploratory laparotomy. After orotracheal intubation, horses were hoisted, placed in dorsal recumbency on a padded surgery table, and received sevoflurane in oxygen for maintenance of anaesthesia. The horses were allowed to breathe spontaneously until instrumented; then, they were mechanically ventilated to maintain the PaCO2between 35 and 45 mmHg. Systolic (SAP), diastolic (DAP), and mean (MAP) arterial blood pressures, heart rate (HR), ECG, respiratory rate, an estimation of the saturation of haemoglobin with oxygen in peripheral arterial blood (SpO2), nasal temperature, end‐tidal CO2(ETCO2), end‐tidal sevoflurane (ETSEVO), and vaporiser concentration were recorded every 5 min post induction; arterial blood samples were obtained soon after induction, at 30 min after induction, and every hour thereafter until surgery was completed. Recovery data including times from the sevoflurane vaporiser being turned off to first movement, to sternal recumbency, and to standing, number of attempts to stand, and recovery score (between 1 = safe, smooth and 6 = stormy, major injury to horse) were collected. Analysis of variance was performed using physiological data collected over 195 min of anaesthesia, the longest time period during which all 8 horses were instrumented. Time effects (P<0.05) for HR, SAP, DAP, MAP, and nasal temperature were identified. Heart rate peaked at 45 min and declined over the course of the procedure. Arterial blood pressure generally decreased over time. Body temperature decreased over time. From 15 to 195 min mean ETSEVOconcentration ranged from 2.0 to 3.3%, while mean vaporiser settings ranged from 3.7 to 5.5%. Three horses received intra‐operative ketamine; all horses received dobutamine infusions; and 2 horses received intra‐operative calcium‐dextrose. Total anaesthesia time was 222–316 min (mean ± s.d. 269 ± 31 min). Time from turning the sevoflurane vaporiser off to first movement was mean ± s.d. 18 ± 15 min; to sternal recumbency was 54 ± 22 min; to standing was 65 ± 27 min; and to returning the horse to the stall in the ward was 78 ± 24 min. Six horses stood on the first attempt; 2 horses stood on the second attempt. The median recovery score was one (1–3). In conclusion, sevoflurane provided a stable, easily controllable anaesthetic plane during prolonged exploratory laparotomies; horses experienced smooth, safe recoveries after maintenance of anaesthesia with sevoflurane following routine anaesthetic induction and post operative xyalzine administration.
Thoracoscopy in the horse: diagnostic and therapeutic indications in 28 cases
Authors: VACHON ANNE M. , FISCHER A. T. 
Published: April 2010

SummaryThirty‐two thoracoscopies were performed in 28 horses. Sixteen horses were affected with pleuropneumonia whereas 12 were affected with various other thoracic conditions. The indications for thoracoscopy was diagnostic in 19 cases, therapeutic in 11 cases and both diagnostic and therapeutic in 2 cases. Twenty‐six thoracoscopies were done standing whereas 6 were performed under general anaesthesia. The specific procedures performed during thoracoscopy were exploratory only (7), biopsy of the lung and lymph nodes (10), drain placement into pleural effusions (2) and abscesses (5), exploration prior to thoracotomy (2), transection of pleural adhesions and decortication (1) and window pericardectomy (2). Diaphragmatic hernia repair (2) and partial pneumonectomy (1) were initiated thoracoscopically but conversion to thoracotomy was necessary for completion. Standing thoracoscopy was well tolerated in most horses. Transient exacerbation of pulmonary compromise evidenced by tachypnoea was readily alleviated by reinflation of the lung. Standing thoracoscopy provided good visualisation of the dorsal and lateral structures of the thorax. The ventral thoracic structures and the cranial ventral diaphragmatic surfaces of the lungs were best visualised in dorsal or lateral recumbency under general anaesthesia. Thoracoscopy is a safe and useful diagnostic and therapeutic tool in horses with thoracic diseases.
Measurement of parathyroid hormone in horses
Authors: ESTEPA J. C. , AGUILERA‐TEJERO E. , MAYER‐VALOR R. , ALMADÉN Y. , FELSENFELD A. J. , RODRÍGUEZ M. 
Published: April 2010

SummaryMeasurement of parathyroid hormone (PTH) in horses was performed on plasma samples using 2 immunoradiometric assays: a human intact PTH assay and a rat amino‐terminal PTH assay. The assays were validated by assessment of their precision, sensitivity and specificity, and also by evaluating PTH changes in the horse in response to variation in blood ionised calcium. Intra‐ and inter‐assay variance, precision and sensitivity were similar for both human and rat assays; however, the rat assay was slightly more precise and sensitive than the human assay. Both assays detected an increase in PTH levels in the horse when blood ionised calcium was decreased and a decline in PTH concentration with hypercalcaemia. Measurement of PTH concentration in samples from healthy horses with the human assay yielded a mean (± s.e.) value of 31.3 ± 4.1 pg/ml. When using the rat assay, PTH values were 44.1 ± 5.3 pg/ml. Plasma samples held for up to 3 months at −20°C did not show a significant change in PTH concentration. In conclusion, the human intact PTH and the rat amino‐terminal assays detected equine PTH and can be used for measurement of this hormone in horses. Quantification of equine PTH using these assays will allow more precise diagnosis of a variety of disorders affecting mineral metabolism in horses.
Clostridium difficileassociated with acute colitis in mares when their foals are treated with erythromycin and rifampicin forRhodococcus equipneumonia
Authors: BÅVERUD V. , FRANKLIN A. , GUNNARSSON A. , GUSTAFSSON A. , HELLANDER‐EDMAN A. 
Published: April 2010

SummaryIn Sweden, mares sometimes develop acute, often fatal, colitis when their foals are treated orally with erythromycin and rifampicin forRhodococcus (R.) equiinfection.Clostridium (C.) difficile, or its cytotoxin, was demonstrated in faecal samples from 5 of 11 (45%) mares with diarrhoea. By contrastC. difficilewas not found in the faecal flora of 12 healthy mares with foals treated forR. equiinfection or in 56 healthy mares with healthy untreated foals. No other enteric pathogen was isolated from any diarrhoeic mare. Of 7 investigated treated foals, 4 had a high (1651.0, 1468.3, 273.0 and 88.8 μg/g) faecal concentration of erythromycin. The dams of those 4 foals developed acute colitis, whereas the dams of 3 foals with a lower (26.3, 4.6 and 3.7 μg/g) faecal erythromycin concentration remained healthy, indicating that there might have been an accidental intake of erythromycin by mares. The foals treated with antibiotics were regarded as asymptomatic carriers and potential reservoirs, asC. difficilewas found in 7 of 16 foals investigated, while 56 untreated foals proved negative. The isolatedC. difficilestrains proved resistant to both erythromycin (MIC >256 mg/l) and rifampicin (MIC >32 mg/l), a fact that may have favoured the growth ofC. difficilein the foal intestine. All mares found positive forC. difficilewere, or had recently been, hospitalised together with their foals, indicating thatC. difficilemay be a nosocomial infection, in horses. The results emphasise that routine testing forC. difficileand its cytotoxin is recommended when acute colitis occurs in mares when their foals are treated with erythromycin and rifampicin. Preventive measures in order to avoid accidental ingestion of erythromycin by mares from the treatment of their foals are suggested.
Effect of moderate exercise on the severity of clinical signs associated with influenza virus infection in horses
Authors: GROSS DIANE K. , HINCHCLIFF K. W. , FRENCH P. S. , GOCLAN SALLY A. , LAHMERS K. K. , LAUDERDALE MARGARET , ELLIS J. A. , HAINES DEBORAH M. , SLEMONS R. D. , MORLEY P. S. 
Published: April 2010

SummaryThe purpose of this experiment was to determine if exercising horses, infected with influenza virus, exacerbates the severity of clinical disease. Eight horses were trained on a treadmill for 42 days and then challenged with aerosolised influenza A/equine/Kentucky/91 (H3N8). Following challenge, 4 horses (exercise group) continued training for 28 days, while the other 4 horses (nonexercise group) were confined to their stalls. All horses developed clinical signs within 36 h of challenge (fever, coughing, and mucopurulent nasal discharge) and clinical scores were greater in the exercise group. Horses developed fever from Days 1–11 post challenge (PC) and were tachypnoeic and tachycardic from Days 1–14 PC. All horses lost weight within 4 days PC, but the exercise group lost an average of 20 kg more than the nonexercise group. All horses developed pneumonia, and ultrasonography revealed pulmonary consolidation and oedema by Day 7 PC that was resolving by Day 14 PC. Endoscopy and transtracheal aspirates showed airway inflammation for up to 21 days PC. While the exercise group exhibited more severe signs of clinical disease, resolution occurred for both groups on approximately Day 14 PC, and no adverse effects were noted at the end of the study. However, the potential long term effects of exercising horses acutely infected with influenza virus are unknown. Until further research is conducted in this area, it appears prudent not to exercise affected horses.