bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endoscopic examination of the tarsal sheath of the lateral digital flexor tendon in horses
Authors: CAUVIN E. R. J. , TAPPREST JACKIE , MUNROE G. A. , MAY S. A. , SCHRAMME M. C. 
Published: April 2010

SummaryThis study was designed to develop a reliable technique for endoscopic examination of the tarsal sheath of the lateral digital flexor tendon of horses. The anatomy of the tendon sheath and associated structures was studied in detail in cadavers before determining portals for the insertion of an arthroscope into the sheath. Approaches into the sheath through the proximal pouch and through theflexor retinaculum, at the level of thesustentaculum tali, were performed and compared in cadavers. The proximal pouch portal permitted visualisation only of the proximal half of the sheath, while the approach through theretinaculumallowed examination of the entire sheath. The normal endoscopic appearance of the tarsal sheath was studied. The endoscopic approach was subsequently used to examine and treat 5 horses with tarsal sheath tenosynovitis, including 2 cases of chronic, traumatic tenosynovitis and 3 of subacute septic tenosynovitis. Four of these horses had fragmentation of thesustentaculum tali. The technique allowed adequate examination of the sheath and debridement of adhesions and lesions within the lumen of the sheath. Fragments dorsal to the medioplantar edge of thesustentaculum talicould not be visualised endoscopically and had to be removed after widening of the wound. All 5 horses survived. Follow‐up enquiries (8–31 months) revealed that the horses were all reported to be sound. Four were performing at their previous level of activity, 1 was used for hacking. The 2 cases presented with chronic tenosynovitis had residual sheath distension with no associated loss of function. A prospective study, including longer term follow‐up investigation, is currently being performed.
The effect of low level laser therapy (LLLT) on wound healing in horses
Authors: PETERSEN S. L. , BOTES C. , OLIVIER A. , GUTHRIE A. J. 
Published: April 2010

SummaryLaser therapy is used in many countries, including South Africa, for the treatment of skin wounds. Low level galium aluminium arsenide (GaAlAs) laser was administered to full thickness skin wounds (3times3 cm) induced surgically on the dorsal aspect of the metacarpophalangeal joints of 6 crossbred horses in a randomised, blind, controlled study. Treated wounds that received a daily laser dosage of 2 J/cm2were compared with nontreated control wounds on the opposite leg. There were no wound complications. Both groups of wounds were cleaned daily using tap water. Wound contraction and epithelialisation were evaluated using photoplanimetry. There were no significant differences in wound contraction or epithelialisation between the laser treated and the control wounds. It was therefore concluded that laser therapy had no clinically significant effect on second intention wound healing in this study.
A method for determination of equine hoof strain patterns using photoelasticity: anin vitrostudy
Authors: DEJARDIN L. M. , ARNOCZKY S. P. , CLOUD G. L. 
Published: April 2010

SummaryDuring impact, equine hooves undergo viscoelastic deformations which may result in potentially harmful strains. Previous hoof strain studies using strain guages have been inconclusive due to arbitrary guage placement. Photoelastic stress analysis (PSA) is a full‐field technique which visually displays strains over entire loaded surfaces. Thisin vitrostudy identifies normal hoof strain patterns using PSA.Custom‐made photoelastic plastic sheets were applied to the hoof surface. The hooves were axially loaded (225 kg) under level and varus/valgus conditions. Strain patterns were video‐recorded through a polariscope. Strains were concentrated between middle and distal thirds of the hoof wall regardless of the loading conditions. This strain distribution appears to result from the differential expansion of the hoof wall under load. Increasing load resulted in higher strains and asymmetric loading resulted in an ipsilateral increase in strain magnitudes without altering strain locations.This study shows that PSA is a reliable method with which to evaluate hoof strains invitroand is sensitive enough to reflect subtle load‐related strain alterations.
Distribution of substance P binding sites in equine airways
Authors: SONEA IOANA M. , BOWKER R. M. , ROBINSON N. E. 
Published: April 2010

SummaryAutoradiography with [125I]‐Bolton Hunter substance P ([I]‐BHSP) was used to detect substance P binding sites in the equine lung. Specific [I]‐BHSP binding sites were very dense over small bronchial vessels, tracheobronchial glands and airway epithelium in large and small airways. The density of [I]‐BHSP binding sites over airway smooth muscle was much lower than in the preceding tissues. Competition with an excess of either a specific neurokinin 1 receptor agonist, or a specific neurokinin 2 receptor agonist indicated that most specific [I]‐BHSP binding sites in the equine lung represent neurokinin 1 receptors. The receptor‐mediated effects of substance P in the equine lung are most likely to involve regulation of vascular tone and airway secretions based upon the density of specific [I]‐BHSP binding sites in these tissues. Activation of intrapulmonary afferent nerves containing Substance P by noxious stimuli such as inhaled allergens or irritants may lead to increased mucus secretion and decreased airway diameter due to vascular congestion.
Prediction of first season stallion fertility of 3‐year‐old Dutch Warmbloods with prebreeding assessment of percentage of morphologically normal live sperm
Authors: PARLEVLIET JOYCE M. , COLENBRANDER B. 
Published: April 2010

SummaryIn the selection procedure to acquire a breeding licence, 3‐year‐old Dutch Warmblood stallions have to undergo a breeding soundness test It is questioned whether this evaluation is predictive of the stallion's fertility results in the first breeding season. Therefore, semen parameters at the beginning of their first breeding season were evaluated and correlated to nonreturn at first cycle and foaling rate of mares bred by stallions (n = 13). The total number of mares inseminated with chilled semen from those stallions was 1055.Semen parameters were recorded on 2 ejaculates, collected 1 h apart. Percentage progressive sperm motility, % morphologically normal from unstained spermatozoa (MNA), % sperm cells with abnormal acrosomes and the total number of spermatozoa were correlated with first cycle nonreturn rate and foaling rate. Mean motility at evaluation was 72 ± 6%. Mean MNA was 62 ± 13%. Mean first cycle nonreturn rate and foaling rate were 58 ± 15% and 69 ± 12%, respectively. A significantly positive correlation (P<0.05) was found between the MNA and first cycle nonreturn rates. Foaling rates were not significantly correlated with semen characteristics and first cycle nonreturn rates. In conclusion, the breeding soundness test is of predictive value for the breeding results in the breeding season following the test. First cycle nonreturn rates reflect fertilising capacity better than foaling rates.
Effects of inhaled dry powder ipratropium bromide on recovery from exercise of horses with COPD
Authors: DUVIVIER DOMINIQUE H. , BAYLY W. M. , VOTION DOMINIQUE , VANDENPUT SANDRINE , ART TANIA , FARNIR F. , LEKEUX P. 
Published: April 2010

SummaryThe present study evaluated ventilatory, cardiovascular and metabolic parameters during recovery from strenuous exercise in horses suffering from a crisis of chronic obstructive pulmonary disease (COPD) and to determine whether ipratropium dry powder inhalation (DPI) before exercise has an effect on these parameters.When 6 saddle horses, affected with COPD, developed airway obstruction, they inhaled placebo and ipratropium (2400 μg/horse), the order being randomly chosen. Pulmonary function tests were then recorded 15 min after inhalation. Following these tests, the horses underwent a strenuous treadmill exercise, followed by a recovery period that consisted of a 10 min walk. Measurements were made at the first and tenth min of recovery. Respiratory flow, O2 and CO2 fractions in the respired gas, pleural pressure changes and heart rate were recorded. Arterial and mixed venous blood samples were analysed for gas tensions, haemoglobin and plasma lactate concentrations. Oxygen consumption (VO2), CO2 production, tidal volume, alveolar oxygen tension (PAO2), alveolar ventilation, the alveolar‐pulmonary capillary oxygen difference ((A‐a)dO2) and total pulmonary resistance (RL) were measured.The PAO2 was the only parameter significantly improved during recovery following ipratropium DPI. This improvement was not accompanied by evidence of improvement of other ventilatory or cardiorespiratory parameters.The results showed that in horses suffering from a crisis of COPD, recovery is characterised by an exercise‐induced bronchodilation. Secondly, ipratropium DPI at a dose of 2400 μg/horse is an effective bronchodilator in these horses at rest but it has little effect on the airway calibre during the recovery period. It is suggested that the short term recovery period is still influenced by exercise‐induced adjustments that may exceed the bronchodilatory effect of inhaled ipratropium that are observed before exercise.
Skeletal muscle metabolic response to exercise in horses with ‘tying‐up’ due to polysaccharide storage myopathy
Authors: VALBERG STEPHANIE J. , MACLEAY JENNIFER M. , BILLSTROM JESSICA A. , HOWER‐MORITZ MELISSA A. , MICKELSON J. R. 
Published: April 2010

SummaryPolysaccharide storage myopathy (PSSM) is a distinct cause of exertional rhabdomyolysis in Quarter Horses that results in glycogen and abnormal polysaccharide accumulation. The purpose of this study was to determine if excessive glycogen storage in PSSM is due to a glycolytic defect that impairs utilisation of this substrate during exercise. Muscle biopsies, blood lactates and serum CK were obtained 1) at rest from 5 PSSM Quarter Horses, 4 normal Quarter Horses (QH controls) and 6 Thoroughbreds with recurrent exertional rhabdomyolysis (TB RER) and 2) after a maximal treadmill exercise test in PSSM and QH controls. In addition, 3 PSSM horses performed a submaximal exercise test. At rest, muscle glycogen concentrations were 2.4x and 1.9x higher in PSSM vs. QH controls or TB RER, respectively. Muscle lactates at rest were similar between PSSM and QH controls but significantly higher in PSSM vs. TB RER. Muscle glucose‐6‐phosphate concentrations were also higher in PSSM horses than controls combined. During maximal exercise, mean muscle glycogen concentrations declined 2.7x more and mean lactate increased 2x more in PSSM vs. QH controls; however, differences were not statistically significant. Blood lactate concentrations after maximal exercise did not reflect generally higher muscle lactate in PSSM vs. QH controls. No change in blood lactate concentrations occurred in PSSM horses with submaximal exercise. Serum CK activity increased significantly 4 h after maximal and submaximal exercise and was significantly higher in PSSM vs. QH controls. These results show that during maximal exercise, PSSM horses utilised muscle glycogen and produce lactic acid via a functional glycolytic pathway and that during submaximal exercise oxidative metabolism was unimpaired. The excessive glycogen storage and formation of abnormal polysaccharide in PSSM horses therefore appear to reflect increased glycogen synthesis rather than decreased utilisation. The specific subset of horses with exertional rhabdomyolysis due to PSSM would likely benefit clinically from a diet low in soluble carbohydrates like grain with fat added as well as gradually increasing daily exercise to reduce excessive glycogen accumulation and enhance utilisation.
Differences in second‐intention wound healing between horses and ponies: histological aspects
Authors: WILMINK JACINTHA M. , VAN WEEREN P. R. , STOLK P. W. TH. , VAN MIL F. N. , BARNEVELD A. 
Published: April 2010

SummaryThe histological aspects of second‐intention healing were studied in 5 horses and 5 ponies. Biopsies were taken weekly from standardised wounds on the metatarsus and femoral biceps muscle of one horse and one pony. Sections were stained to enable cell counting and the detection of DNA synthesis, fibrin, smooth muscle actin (SMA), collagen, and bacteria.In the ponies, the number of polymorphonuclear leucocytes (PMNs) was high during the first 3 weeks and subsequently decreased rapidly. In the horses, the initial number of PMNs was lower, but remained persistently elevated during the evaluation period. PMNs were found mainly in the superficial zones. Significantly more fibrin was present in the wounds of the horses. No significant differences were observed in the number of fibroblasts, the amounts of SMA and collagen. However, myofibroblasts were significantly less regularly organised in the wounds of the horses, particularly in the metatarsal wounds. The mitotic activity of the epithelium was temporally reduced in week 3. The mitotic activity of the granulation tissue was initially high but declined rapidly from week 1 onwards, with the exception of the metatarsal wounds of the horses, in which mitotic activity remained significantly higher.Histology confirmed and explained the macroscopical differences in wound healing between horses and ponies by the strict organisation of the myofibroblasts and the more effective acute inflammation in the ponies. Stimulation of the organisation of myofibroblasts and improvement of the efficacy of the inflammatory response in horses may therefore result in better second‐intention wound healing in horses in clinical practice.
Galloping exercise induces regional changes in bone density within the third and radial carpal bones of Thoroughbred horses
Authors: FIRTH E. C. , DELAHUNT J. , WICHTEL J. W. , BIRCH H. L. , GOODSHIP A. E. 
Published: April 2010

SummaryThis study was performed to test the hypothesis that a localised bone hypertrophy could occur within the subchondral cancellous architecture of the third and radial carpal bones. Using 2 levels of controlled and defined exercise, it was observed that a high intensity treadmill exercise protocol resulted in functional adaptation of the carpal bones. The increase in trabecular thickening and density was seen to be localised to those regions underlying common sites of cartilage degradation, the interface of the thickened trabeculae with the normal architecture in the third carpal bone was coincident with a common site of clinical fractures. The bone changes were determined both qualitatively on examination of slab radiographs and quantified by dual energy x‐ray absorptiometry.The findings from this study are relevant to mechanical factors involved in the pathophysiology of joint degeneration. The potential clinical implications of this study are in relation to changes in the type and duration of exercise regimens used in training of equine athletes. The rapid response of bone to mechanical stimulation has implications in the longer term for localised cartilage degradation. Imaging techniques could be developed to monitor these early bone changes in the specific areas identified in this study and thus allow appropriate changes in training intensity to minimise subsequent damage to the articular surface.
Thoracic trauma in newborn foals
Authors: JEAN D. , LAVERTY S. , HALLEY J. , HANNIGAN D. , LÉVEILLÉ R. 
Published: April 2010

SummaryIn a report describing life ending fractures (255 horses) from the Livestock Disease Diagnostic Center, Kentucky (1993 and 1994), 32 foals had rib fractures. The purpose of our study was to examine the incidence of rib fractures in newborn foals on a Thoroughbred studfarm by physical and radiographic examination, to determine factors which may contribute to the problem and to document any clinical consequences. All foals (263) included were examined within 3 days of birth. The thoracic cage was palpated externally for abnormalities and all foals were placed in dorsal recumbency to evaluate thoracic cage symmetry. Radiographs were used to diagnose foals with thoracic cage asymmetry (TCA) and rib fracture (RF). A diagnosis of costochondral dislocation (CD) was made when no radiographic evidence of fracture was present but there was severe TCA. Fifty‐five foals (20.1%) had TCA (9 RF). One to 5 ribs were fractured on 9 of 40 radiographic studies. No consequences of the thoracic trauma was detected clinically, radiographically or ultrasonographically in this group of foals or at a 2‐ and 4‐week follow‐up examination. The percentage of foals with a history of abnormal parturition was higher in the TCA foals (15%) compared to the normal foals (6.8%). There were more primiparous dams in the TCA group than in the normal foal group. Fillies (56.6%) had a higher incidence of birth trauma than colts (43.4%). This study demonstrates that thoracic trauma is often present in newborn foals and may not always be of clinical significance. Dystocia foals and foals from primiparous mares should be considered high risk for thoracic trauma.
Hyperkalaemic periodic paralysis in homozygous and heterozygous horses: a co‐dominant genetic condition
Authors: NAYLOR J. M. , NICKEL D. D. , TRIMINO G. , CARD C. , LIGHTFOOT K. , ADAMS G. 
Published: April 2010

SummaryHistorical, clinical and experimental data were collected from 9 horses homozygous for HYPP (H/H). All showed episodes of respiratory stertor, described as a rattling or honking sound, usually within the first weekpost partum.Five horses had one or more episodes of dysphagia, in 3 horses this was accompanied by drooling and in 3 by weight loss. In comparison, only one of 35 contemporaneous half siblings (of which approximately half would be expected to be of the H/N genotype and half N/N) was observed to have respiratory stertor prior to weaning and none had problems with dysphagia.One mature homozygous stallion was infertile secondary to urospermia. Six homozygous horses died or were subjected to euthanasia; 4 age less than a year, one age 20 months and one age 5 years. The remaining 3 cases were still alive at the end of the study.A comparison of homozygous and heterozygous horses using standardised potassium chloride challenge testing indicated that during attacks homozygotes showed significantly more frequent signs of drooling, prolapse of the third eyelid, respiratory stridor and weakness than heterozygous horses. Homozygotes also had significantly more total abnormalities (including myotonic discharges, high frequency repetitive discharges, and spontaneous activity) on electromyographic examination than heterozygotes.These data imply that HYPP is inherited as a co‐dominant genetic defect, because the homozygotes showed more severe clinical signs of disease than heterozygotes. Homozygous foals would be expected to be produced in 25% of matings in which both parents are heterozygous. Owners and veterinarians should be aware of the risks of this mating.
Investigations on the ability of clenbuterol hydrochloride to reduce clinical signs and inflammation associated with equine influenza A infection
Authors: KÄSTNER SABINE B. R. , HAINES DEBORAH M. , ARCHER JOY , TOWNSEND H. G. G. 
Published: April 2010

SummaryTwenty‐four Quarter Horse and Quarter Horse‐cross yearlings were experimentally infected with influenza A virus (Influenza A/equine/Saskatoon/90 [H3N8]) by nebulisation. In a double blind controlled trial the horses were randomly assigned to 3 groups of 8 animals.Group 1received a placebo, (carrier syrup),Group 2the labelled dose andGroup 3twice the labelled dose of clenbuterol hydrochloride. All treatments were givenper osb.i.d. for 10 days and started on the day of infection. The horses were monitored for clinical signs of influenza infection for 14 days. Bronchoalveolar lavages were performed 4 days prior to, and 5 and 13 days after infection. Cell counts and concentrations of prostaglandin E2and prostaglandin F2αin the lavage fluid were determined. Blood samples for haematology and serology were taken 4 days before, on the day of infection, 5, 9 and 13 days after infection. All horses experienced a typical influenza infection with fever, coughing and secondary bacterial infections with mainlyActinobacillusspp. andStreptococcusspp. There was no statistically or clinically significant effect of treatment with clenbuterol hydrochloride on measured clinical or laboratory parameters within 14 days of infection.
New approaches to detect cortisol administration in the horse
Authors: POPOT M. A. , LACABARATZ E. , GARCIA P. , LAROUTE V. , BONNAIRE Y. , TOUTAIN P. L. , COWAN D. A. 
Published: April 2010

SummaryThe cortisol threshold concentration of 1.0 μg/ml in horse urine adopted by the International Federation of the racing Authorities in 1994 is specific. However, an increase in the sensitivity for the detection of cortisol administration would be helpful. Previous studies have shown that 20β‐dihydrocortisol concentration in urine would be a good indicator of cortisol administration. The purpose of the present work was to estimate the population parameters and the critical values of 20β‐dihydrocortisol and 20β‐dihydrocortisone concentration in urine compared with that of cortisol. Using the same probability (1.1 times 10−4) which was used for the establishment of the official cortisol threshold, the critical values of 5000 ng/ml for 20β‐dihydrocortisol and 350 ng/ml for 20β‐dihydrocortisone were obtained. Considering these 2 critical values for 20β‐dihydrocortisol and 20β‐dihydrocortisone, the time during which a horse could be declared positive is significantly increased.
Attenuation by phenylbutazone of the renal effects and excretion of frusemide in horses
Authors: DYKE T. M. , HINCHCLIFF K. W. , SAMS R. A. 
Published: April 2010

SummaryThe objectives of this study were to determine the effect of phenylbutazone premedication on the pharmacokinetics and urinary excretion of frusemide in horses; and on frusemide‐induced changes in urinary electrolyte excretion. Six Standardbred mares were used in a 3‐way crossover design.The pharmacokinetics and renal effects of frusemide (1 mg/kg bwt i.v.) were studied with and without phenylbutazone premedication (8.8 mg/kg bwtper os24 h before, followed by 4.4 mg/kg bwt i.v. 30 min before frusemide administration). A control (saline) treatment was also studied.Administration of frusemide without phenylbutazone led to diuresis, natriuresis, kaliuresis and chloruresis, and altered the ratio of sodium:chloride excretion from 0.4 to 1.0 in the first hour of diuresis. When frusemide and phenylbutazone were administered, sodium and chloride excretion in the first hour were significantly (P<0.05) reduced by 40 and 32%, respectively, when compared to frusemide administration without phenylbutazone. The fractional clearance of sodium and chloride was also significantly reduced. Potassium excretion, potassium fractional clearance and the ratio of sodium to chloride excretion were not affected by administration of phenylbutazone. During peak diuresis, phenylbutazone did not affect the efficiency of frusemide with respect to electrolye excretion.The plasma disposition of frusemide was not affected by phenylbutazone. However, the renal excretion of frusemide decreased by approximately 25%. We conclude that the decreased urinary excretion of frusemide by phenylbutazone led to an attenuation of frusemide‐induced increases in urinary excretion of sodium and chloride. Since the efficiency of frusemide was not affected by phenylbutazone, we conclude that phenylbutazone attenuates the renal excretion of frusemide without inhibiting the intrarenal activity of frusemide in horses.