bluuebunny/crossref_metadata_2025_split huggingface dataset:
The prevalence of secondary dentinal lesions in cheek teeth from horses with clinical signs of pulpitis compared to controls
Authors: CASEY M. B. , TREMAINE W. H. 
Published: July 2010

SummaryReasons for performing study: With the advent of detailed oral examination in horses using dental mirrors and rigid endoscopy, secondary dentinal lesions are observed more frequently. More information regarding the association of secondary dentinal defects with apical dental disease would improve the sensitivity of oral examination as a diagnostic aid for pulpitis.Objectives: To assess prevalence and severity of secondary dentinal defects observed on examination of occlusal surfaces of cheek teeth (CT) from horses showing clinical signs of pulpitis compared to asymptomatic controls.Methods: Records from all cases of equine CT exodontia at the University of Bristol over a 4 year period were examined. Case selection criteria included the presence of clinical signs of pulpitis, an intact extracted tooth and availability of a complete history and follow up. Cases where coronal fracture or periodontal pocketing featured were excluded. CT from cadavers with no history of dental disease served as normal controls. Triadan positions and eruption ages of control teeth were matched with those of teeth extracted from cases. CT from selected cases and control teeth were examined occlusally. Secondary dentinal defects were identified and graded. Prevalence of occlusal lesions in CT with pulpitis and controls was compared.Results: From the records of 120 horses where exodontia was performed, 40 cases matched selection criteria. Twenty‐three mandibular and 21 maxillary CT were extracted from cases. The controls consisted of 60 mandibular and 60 maxillary CT from 7 cadaver skulls. Secondary dentinal defects were significantly over‐represented in CT extracted from cases of pulpitis (P<0.001). Of diseased mandibular CT, 56.5% had defects compared to none of the controls. Of diseased maxillary CT, 57% had defects compared with 1.6% of controls. Multiple defective secondary dentinal areas and severe lesions were more prevalent in diseased mandibular CT compared with diseased maxillary CT.Conclusions and practical significance: Careful examination of occlusal secondary dentine is an essential component in investigation of suspected pulpitis in equine CT.
Successful treatment of persistent dorsal displacement of the soft palate and evaluation of laryngohyoid position in 15 racehorses
Authors: ORTVED K. F. , CHEETHAM J. , MITCHELL L. M. , DUCHARME N. G. 
Published: July 2010

SummaryReasons for performing study:Caudal descent of the larynx has been proposed to be associated with intermittent dorsal displacement of the soft palate (DDSP) as it leads to a loss of the seal between the epiglottis and soft palate but further investigation of this theory is required.Objectives:To evaluate laryngohyoid position of horses with persistent DDSP in comparison to horses with intermittent DDSP and evaluate the outcome of treatment.Hypotheses:Horses with persistent DDSP have a different laryngohyoid position compared to those with intermittent DDSP. Horses with persistent DDSP can be returned successfully to racing with a laryngeal tie‐forward procedure.Methods:Medical records of 15 racehorses presented for persistent DDSP between 2002 and 2007 were reviewed. Age, sex and breed matched horses diagnosed with intermittent DDSP were used as a comparison group. Treatment of all horses was performed by laryngeal tie‐forward, 8/15 horses with persistent DDSP had a subsequent laser staphylectomy. Preoperative laryngohyoid position was compared between the 2 groups using a radiographic reference system. Surgical effect on position was assessed by comparing pre‐ and post operative radiographic measurements. Outcome was assessed by return to racing and comparison of pre‐ and post operative race earnings ($).Results:Thirteen of 15 horses with persistent DDSP returned to racing. Seven of 15 horses were treated with laryngeal tie‐forward alone while 8/15 horses were also treated with a laser staphylectomy. Horses with persistent DDSP had a more caudal larynx (ossification of the thyroid cartilage) (13 mm, P = 0.014), a more caudal (10 mm, P = 0.044) and dorsal (7 mm, P = 0.01) basihyoid bone, and a more dorsal thyrohyoid‐thyroid articulation (10 mm, P = 0.002) than horses with intermittent DDSP.Conclusions and potential relevance:Racehorses with persistent DDSP can be treated successfully by laryngeal tie‐forward or by laryngeal tie‐forward followed by laser staphylectomy. Horses with persistent DDSP have a more caudal larynx and more caudal and dorsal basihyoid bone than horses with intermittent DDSP.
Standing magnetic resonance imaging detection of bone marrow oedema‐type signal pattern associated with subcarpal pain in 8 racehorses: A prospective study
Authors: POWELL S. E. , RAMZAN P. H. L. , HEAD M. J. , SHEPHERD M. C. , BALDWIN G. I. , STEVEN W. N. 
Published: July 2010

SummaryReason for performing study:The proximal metacarpal region is a common site of origin of lameness in the performance horse. A number of disease entities are recognised as causes of proximal metacarpal lameness but a definitive diagnosis is often elusive. Magnetic resonance imaging (MRI) is hypothesised to offer advantages over traditional imaging modalities in the investigation of proximal metacarpal pain.Objective:To describe clinical and imaging features of cases of lameness in racehorses arising from the proximal metacarpal region in which standing MRI identified ‘bone marrow oedema‐type’ (BMO‐type) signal patterns.Methods:Records for all horses undergoing standing MRI of the proximal metacarpus/distal carpus from September 2006 to December 2008 were reviewed. Cases underwent a standardised protocol for diagnostic analgesia, radiography and ultrasonography of the proximal metacarpus and distal carpus. Cases with proximal metacarpal lameness displaying a characteristic BMO‐type signal pattern on MRI were identified and outcomes analysed.Results:Eight cases were identified with characteristic MRI findings of extensive hyperintensity on T2* gradient echo and short tau inversion fast spin echo sequences and corresponding hypointensity on T1 gradient echo images within the palmaroproximal aspect of the third metacarpal bone. Follow‐up information was available for all cases; at the time of writing 7/8 had returned to full work and were free from lameness.Conclusions:The BMO‐type signal patterns visible on MR images in these cases may signal the existence of a previously under‐diagnosed pathological process associated with proximal metacarpal lameness in racehorses. This finding is postulated to be associated with a stress reaction and possible prodromal stress fracture of the palmaroproximal metacarpus not appreciable radiographically or ultrasonographically.Potential relevance:MRI of the proximal metacarpal region permits detection of pathological processes, which may elude conventional imaging and, therefore, has important therapeutic and prognostic implications in these cases.
Anatomical studies of maxillary cheek teeth infundibula in clinically normal horses
Authors: FITZGIBBON C. M. , DU TOIT N. , DIXON P. M. 
Published: July 2010

SummaryReasons for performing study: Although clinical disorders of equine maxillary cheek teeth (CT) infundibula are common, anatomical knowledge of these structures is poor.Hypothesis: Anatomical examinations of sectioned CT infundibula will better define their shapes and sizes and allow identification of infundibular cemental variations and changes.Material and methods: Cheek teeth were extracted post mortem from 33 horses, aged 3–30 years, without a clinical history of dental disease. The CT were sectioned longitudinally in the bucco‐palatal plane through the widest aspects of both infundibula. The infundibular surfaces were then assessed morphologically, including by measurements of areas of cemental variations and changes. Specimens from selected teeth were examined histologically.Results: Infundibular length and infundibular surface area, and infundibular length as a proportion of dental crown length progressively decreased with age, e.g. infundibular length was up to 89 mm after eruption to 2 mm in one older horse. Triadan 06 and 09 positions had significantly shorter CT and therefore infundibula, than the other 4 Triadan positions. Only 11.7% of infundibula were filled completely with normal appearing cementum, 8.2% of infundibula (especially the 09 position) had complete cemental caries; 22.6% of infundibula had areas with cemental hypoplasia and the remaining 57.5% of infundibulae had a variety of other cemental appearances, including the presence of central defects, localised occlusal caries and cemental discolourations. Histology showed the presence of an apical blood supply to infundibular cement in younger horses.Conclusions: Anatomical variations of CT infundibular cement are very common and some changes, such as areas of localised cemental hypoplasia, may predispose to the development of infundibular caries.Potential relevance: This more complete description and quantification of CT infundibular anatomy should allow more rational assessment and treatment of equine CT infundibular disorders.
Arterial blood gas parameters of normal foals born at 1500 metres elevation
Authors: HACKETT E. S. , TRAUB‐DARGATZ J. L. , KNOWLES Jr. J. E. , TARR S. F. , DARGATZ D. A. 
Published: July 2010

SummaryReasons for performing study: Arterial blood gas analysis is widely accepted as a diagnostic tool to assess respiratory function in neonates. To the authors' knowledge, there are no published reports of arterial blood gas parameters in normal neonatal foals at altitude.Objective: To provide information on arterial blood gas parameters of normal foals born at 1500 m elevation (Fort Collins, Colorado) in the first 48 h post partum.Hypothesis: Foals born at 1500 m will have lower PaO2 and PaCO2 than foals born at sea level due to low inspired oxygen and compensatory hyperventilation occurring at altitude.Methods: Sixteen foals were studied. Arterial blood gas analysis was performed within 1 h of foaling and subsequent samples were evaluated at 3, 6, 12, 24 and 48 h post partum. Data were compared to those previously reported in healthy foals born near sea level.Results: Mean PaO2 was 53.0 mmHg (7.06 kPa) within 1 h of foaling, rising to 67.5 mmHg (9.00 kPa) at 48 h post partum. PaCO2 was 44.1 mmHg (5.88 kPa) within one hour of foaling, falling to 38.3 mmHg (5.11 kPa) at 48 h. Both PaO2 and PaCO2 were significantly lower in foals born at 1500 m elevation than those near sea level at several time points during the first 48 h.Conclusions and potential relevance: Foals at 1500 m elevation undergo hypobaric hypoxia and compensatory hyperventilation in the first 48 h. Altitude specific normal arterial blood values are an important reference for veterinarians providing critical care to equine neonates.
Equine laminitis: Induced by 48 h hyperinsulinaemia in Standardbred horses
Authors: De LAAT M. A. , McGOWAN C. M. , SILLENCE M. N. , POLLITT C. C. 
Published: July 2010

SummaryReasons for performing study: Hyperinsulinaemia is known to induce laminitis experimentally in healthy ponies with no history of the condition. Horses are more insulin sensitive than ponies and whether prolonged hyperinsulinaemia and euglycaemia would have a similar laminitogenic effect requires study.Objectives: To determine if laminitis results when the prolonged euglycaemic hyperinsulinaemic clamp technique (p‐EHC) is applied to clinically normal Standardbred horses, and to monitor hoof wall temperature seeking an association between vascular activity and laminitis development.Methods: Eight young, clinically normal Standardbred horses were assigned into 4 pairs and within each pair, one was assigned randomly to either treatment (n = 4) or control (n = 4) groups. Treated horses received continuous infusions of insulin and glucose until clinical signs of laminitis developed, at which point the horses were subjected to euthanasia. Control horses received an equivalent volume of a balanced electrolyte infusion for the same period. Hoof wall surface temperature (HWST) was monitored continuously throughout the experimental period.Results: All horses in the treatment group were calculated to have normal insulin sensitivity. All treated horses, and none in the control group, developed laminitis (P = 0.01). Pronounced digital pulses were a feature of the treatment group, while insignificant digital pulses occurred in control horses. HWST was higher and less variable in treated horses once hyperinsulinaemia was established.Conclusions: Healthy Standardbred horses subjected to prolonged hyperinsulinaemia develop laminitis within 48 h, demonstrating that laminitis in horses can be triggered by insulin.Potential relevance: Insulin resistance and the associated hyperinsulinaemia place horses and ponies at risk of developing laminitis. This study demonstrates a need for prompt management of the persistent hyperinsulinaemia seen in some endocrinopathies.
Occlusal fissures of the equine cheek tooth: Prevalence, location and association with disease in 91 horses referred for dental investigation
Authors: RAMZAN P. H. L. , PALMER L. 
Published: July 2010

SummaryReason for performing study: Fissures of the occlusal surface of the equine cheek tooth are poorly understood and their association with dental disease is unknown.Objective: To describe the prevalence and location of occlusal fissures in the cheek teeth (CT) of a group of horses referred for dental investigation/treatment, and determine association with intercurrent dental disease.Methods: Digital video recordings of oral endoscopic examinations for all horses referred to the Rossdales Equine Hospital for dental investigation from November 2006 to June 2009 were reviewed. Location of occlusal fissures in relation to both Triadan tooth position and pulpar secondary dentine was recorded; direction of fissure and concurrent involvement of enamel was also documented. The CT location considered at the time of examination to be the primary site/s of disease was correlated with presence of fissures on these teeth.Results: 91 cases meeting the inclusion criteria were identified. Occlusal fissures were documented in 58.2% (53/91) cases, with a total of 227 CT being affected. Fissures were most prevalent mid‐arcade. The majority (92.1%) of fissures in maxillary CT were associated with the caudal palatal pulp horn. Fissures in mandibular CT were predominantly associated with the buccal pulp horns (95.7%). There was no significant difference in the median number of CT with fissures in relation to gender. There was no correlation between age (r2= 0.01) of horse and number of CT with fissures. A significantly greater number of CT with multiple occlusal fissures was found in mandibular compared to maxillary arcades. No correlation was found between presence of fissures and location of individual CT considered to be primarily responsible for presentation.Conclusions: Occlusal fissures in this group of animals were common and not correlated to primary site of dental disease.Potential relevance: In horses subjected to dental investigation, occlusal fissures of the cheek teeth should not be considered an indicator of tooth compromise. Location and direction of fissure propagation in most cases is inconsistent with occlusal fissures being causally implicated in slab fractures of cheek teeth, although site predilection may indicate a possible association with masticatory forces.
Clinical and imaging features of suspected prodromal fracture of the proximal phalanx in three Thoroughbred racehorses
Authors: RAMZAN P. H. L. , POWELL S. E. 
Published: July 2010

SummarySagittal fracture of the proximal phalanx (P1) is an important musculoskeletal injury of the performance horse. Although widely considered to be monotonic in nature, there is emerging evidence that some P1 fractures may have stress‐injury aetiology. Three cases are described in which imaging features found were suggestive of prodromal bone injury. All cases returned to full performance use after a period of rest. The authors conclude that it is possible that some P1 fractures in the Thoroughbred racehorse may develop through stress/fatigue injury pathways. It is proposed that intervention prior to overt fracture may be possible in some cases.
Return to work following unilateral enucleation in 34 horses (2000–2008)
Authors: UTTER M. E. , WOTMAN K. L. , COVERT K. R. 
Published: July 2010

SummaryReasons for study:The effect of unilateral enucleation on vision and potential loss of performance in horses has received little study.Objective:To evaluate the likelihood of return to prior discipline following unilateral enucleation in horses, assessing the role of age at enucleation, equine discipline, reason for enucleation, time to vision loss and eye enucleated.Hypothesis:Unilateral enucleation has no significant effect on likelihood of return to work in horses, for both right and left eyes, across age and discipline.Method:A retrospective review of medical records identified 92 horses that underwent unilateral enucleation at the University of Pennsylvania New Bolton Center from April 2000–April 2008. Case variables determined from the medical record included breed and sex of horse, age at enucleation, which eye was enucleated, reason for enucleation and onset of vision loss. Pre‐ and post operative occupations were determined by telephone interview with the owner or trainer of each horse.Results:Based on hospital surgery logs, 92 enucleations were performed over the 8 year period and 77 records were available for review, with follow‐up information available for 34 horses. Of these, 29/34 (85%) horses returned to work in pleasure or trail riding (11/13), flat racing (7/10), hunter/jumpers (4/4), dressage (3/3), group lessons (1/1), eventing (1/1), steeplechase (1/1) and as a broodmare (1/1). Four of 5 horses (4/34, or 12% sample) that did not return to work (2 pleasure and 2 racing) were retired due to anticipated or perceived decrease in performance or behaviour change following unilateral enucleation, with the remaining horse retired from racing for lameness issues unrelated to enucleation. Twenty‐two of 25 horses (88%) with acute vision loss and 7/9 horses (78%) with gradual vision loss returned to their previous discipline.Conclusions:Horses are able to return to a variety of occupations after unilateral enucleation.
Relationship of horse owner assessed respiratory signs index to characteristics of recurrent airway obstruction in two Warmblood families
Authors: LAUMEN E. , DOHERR M. G. , GERBER V. 
Published: July 2010

SummaryReasons for performing study: The horse owner assessed respiratory signs index (HOARSI‐1–4, healthy, mildly, moderately and severely affected, respectively) is based on owner‐reported clinical history and has been used for the investigation of recurrent airway obstruction (RAO) genetics utilising large sample sizes. Reliable phenotype identification is of paramount importance in genetic studies. Owner reports of respiratory signs have shown good repeatability, but the agreement of HOARSI with an in‐depth examination of the lower respiratory tract has not been investigated.Objectives: To determine the correlation of HOARSI grades 3/4 with the characteristics of RAO and of HOARSI‐2 with the characteristics of inflammatory airway disease. Further, to test whether there are phenotypic differences in the manifestation of lung disease between families.Methods: Seventy‐one direct offspring of 2 RAO‐affected Warmblood stallions (33 from the first family, 38 from the second) were graded as HOARSI‐1–4 and underwent a clinical examination of the respiratory system, arterial blood gas analysis, endoscopic mucus scoring, cytology of tracheobronchial secretion (TBS) and bronchoalveolar lavage fluid (BALF), and clinical assessment of airway reactivity to methacholine chloride.Results: HOARSI‐3/4 animals in clinical exacerbation showed signs consistent with RAO: coughing, nasal discharge, abnormal lung sounds and breathing pattern as well as increased numbers of neutrophils in TBS and BALF, excessive mucus accumulation and airway hyper‐responsiveness to methacholine. HOARSI‐3/4 horses in remission only had increased amounts of tracheal mucus and TBS neutrophil percentages. Clinical phenotypes were not significantly different between the 2 families.Conclusions and clinical relevance: HOARSI reliably identifies RAO‐affected horses in our population.
Dysautonomia in a six‐year‐old mule in the United States
Authors: WRIGHT A. , BEARD L. , BAWA B. , BRAS J. 
Published: July 2010

SummaryEquine dysautonomia, also known as equine grass sickness (EGS), is a well documented disease in several countries. To the authors’ knowledge, EGS has not been reported previously in North America. This report describes EGS in a 6‐year‐old female mule in the USA. Failure initially to consider EGS resulted in a delayed diagnosis. EGS should be considered as a differential diagnosis and appropriate diagnostic tests performed in similar cases in North America.
Morphological study of tracheal shape in donkeys with and without tracheal obstruction
Authors: POWELL R. J. , Du TOIT N. , BURDEN F. A. , DIXON P. M. 
Published: July 2010

SummaryReason for performing study:There is limited information on the gross tracheal morphology of donkeys with or without tracheal abnormalities.Objectives:To: 1) examine the morphology of tracheas of donkeys with and without clinical and/orpost mortemevidence of tracheal obstruction; 2) record the cross‐sectional dimensions and shapes of tracheal rings at fixed sites; and 3) document prevalence, sites and characteristics of detected tracheal abnormalities.Methods:The tracheas of 75, predominantly aged (median age 30 years, range 7–48 years) donkeys that died or were subjected to euthanasia on humane grounds were examined. Five had severe dyspnoea due to tracheal obstruction (with intercurrent lung disease in 3), while 7 hadpost mortemevidence of severe tracheal airway obstruction. Every 5th tracheal ring was dissected free and the inner and outer vertical and transverse dimensions and cross sectional areas were measured. Each dissected ring was photographed and the shape of the trachea was classified as normal or, in one of 6 abnormal grades, according to the type and degree of structural abnormality present.Results:The tracheas had a mean of 43 (range 34–50) tracheal rings that tended to be more oval in shape in the distal cervical region. Only 31.2% of rings examined had a circular to oval shape. Dorso‐ventral flattening was present in 0.9% of tracheal rings, dorsal ligament separation in 24.4%, slight cartilage deformity in 26.0%, moderate cartilage deformity in 10.4%, marked cartilage deformity in 1.9% and miscellaneous other abnormalities in 4.9% of tracheal rings. The 12 donkeys withanteorpost mortemevidence of tracheal obstruction had significantly increased tracheal abnormality grade in comparison to the remaining donkeys.Conclusions and potential relevance:Structural tracheal abnormalities are present in most old donkeys, but generally do not cause clinical problems in these sedentary animals unless intercurrent pulmonary disease is present.