bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrospective analysis of historical, clinical, ultrasonographic, serum biochemical and haematological data in prognostic evaluation of equine liver disease
Authors: DURHAM A. E. , NEWTON J. R. , SMITH K. C. , HILLYER M. H. , HILLYER L. L. , SMITH M. R. W. , MARR C. M. 
Published: April 2007

SummaryReasons for performing study: Results of noninvasive tests of liver disease do not always correlate with the degree of hepatic disease nor outcome of the case.Objective: To investigate the prognostic value of data collected using noninvasive tests during the investigation of cases of suspected liver disease in mature horses.Hypothesis: Much of the data gathered during the investigation of suspected hepatopathy cases offers little prognostic guidance and interpretation of such data can be misleading.Methods: The results from a range of common and noninvasive diagnostic techniques applied in 116 mature horses with suspected liver disease, were assessed for their ability to predict survival within a 6 month period.Results: A significantly poorer prognosis was found in association with clinical signs suggestive of liver disease, presence of hepatic encephalopathy, ultrasonographic abnormalities, increased serum globulins, increased total bile acids (TBA), increased alkaline phosphatase (AP), increased gamma‐glutamyl transferase (γGT), erythrocytosis, leucocytosis, low serum albumin and low serum urea. Additional significant novel findings of interest included an association between increased plasma fibrinogen and low serum creatinine concentrations with nonsurvival in cases of liver disease, an association between raised serum concentrations of AP and γGT with biliary hyperplasia and also an association between hepatic fibrosis, haemosiderosis and biliary hyperplasia with ultrasonographically detected hepatic abnormalities.Conclusions: The most useful noninvasive prognostic test in cases of suspected liver disease in mature horses is the severity of clinical signs. Other data may be of some limited prognostic value.Potential relevance: Application of the findings in this study may not be directly applicable to other case populations. However, the findings should at least be considered when prognosis is based on similar criteria.
Occurrence of infectious upper respiratory tract disease and response to vaccination in horses on six sentinel premises in northern Colorado
Authors: MUMFORD E. L. , TRAUB‐DARGATZ J. L. , CARMAN J. , CALLAN R. J. , COLLINS J. K. , GOLTZ K. L. , ROMM S. R. , TARR S. F. , SALMAN M. D. 
Published: April 2007

SummaryReasons for performing study: Horses vaccinated against common agents of infectious upper respiratory disease (IURD) may not have detectable serum antibody and may not be protected from clinical disease.Objectives: The objectives of this study were to 1) investigate the serological response of horses to vaccination against influenza virus (H3N8 and H7N7) and equine herpesviruses (EHV) in a field setting and 2) evaluate associations among vaccination status, serum antibody concentrations, and occurrences of IURD in monitored horses.Methods: In this study, horses on 6 Colorado premises were vaccinated parenterally against influenza virus and EHV, and serological response evaluated. Horses were monitored, and biological samples collected from individuals with clinical IURD and control horses.Results: Of 173 horses, 61 (35.3%), 21 (12.1%) and 4 (2.3%) seroconverted in response to vaccination against EHV, influenza virus H7N7 and influenza virus H3N8, respectively.Conclusions: Outbreaks of IURD in study horses were associated with influenza virus H3N8 andStreptococcus equiinfection, and serological response to vaccination with conventional products was poor.Potential relevance: These results confirm that horses may not respond with detectable serological responses to conventional vaccination against common respiratory viruses and, therefore, suggest that alternate methods of protecting horses against common respiratory viruses should be sought.
Influence of liver copper status of mare and newborn foal on the development of osteochondrotic lesions
Authors: WEEREN P. R. van , KNAAP J. , FIRTH E. C. 
Published: April 2007

Summary Reason for performing study: To elucidate the highly contentious role of copper in the pathogenesis of osteochondrosis. Hypothesis: There would be no relationship between liver copper concentration of mares and foals and incidence of radiographically detectable osteochondrotic lesions in foals and yearlings was tested. Methods: Liver copper concentration was assessed in biopsies taken within 4 days after birth from both mares and foals and from the same foals at age 5 months. Biopsies were taken in the standing, sedated animal under ultrasonographic guidance. Radiographs were taken of both hocks (lateromedial, dorsoplantar and dorsomedial‐plantarolateral oblique views) and stifles (lateromedial and caudolateral‐craniomedial oblique views) at ages 5 and 11 months and scored for the presence and severity of osteochondrotic lesions. Results: Copper concentrations in newborn foals were high with a large variation (351 ± 201 mg/kg DM). They declined until reaching values comparable to those in mature animals at 5 months (20 ± 8 mg/kg DM; mares: 19 ± 20 mg/kg DM). Radiographic osteochondrotic lesions decreased in number and severity from 5 to 11 months. This pattern was more predominant in the stifle than in the hock, as has been described previously. Conclusions: There was no relationship between foal or mare liver copper concentration and osteochondrosis status at either 5 or 11 months. However, osteochondrotic lesions in foals with low‐level copper status at birth decreased significantly less in number and severity than those in foals with high‐level copper status at birth. Potential relevance: It is concluded that copper is not likely to be an important factor in the aetiopathogenesis of osteochondrosis, but this study indicates that there may be a significant effect of high copper status on the natural process of repair of early lesions.
Magnetic resonance imaging of the equine foot: 15 horses
Authors: DYSON S. , MURRAY R. , SCHRAMME M. , BRANCH M. 
Published: April 2007

Summary Reasons for performing study: Foot pain is a common cause of equine lameness and there have been significant limitations of the methods available for the diagnosis of the causes of foot pain (radiography, nuclear scintigraphy and ultrasonography). Until recently, magnetic resonance imaging (MRI) in the horse has been limited to examination of cadaver limbs. Objectives: Our purpose was to 1) describe MRI of the foot in live horses, 2) describe MRI findings in horses with foot pain in which a definitive diagnosis could not be established by alternative means and 3) correlate MRI findings with other methods of clinical investigation. Methods: The feet of 15 horses with unilateral (12) orbilateral (3), forelimb (14) or hindlimb (1) lameness associated with foot pain of previously ill‐defined origin were examined using MRI. The horses were examined in right lateral recumbency under general anaesthesia, with the feet positioned in the isocentre of a flared end 1.5 Tesla GE Signa Echospeed magnet. Images were obtained in sagittal, transverse and dorsal planes using 3‐dimensional (3D) T2* gradient echo (GRE), spoiled gradient echo, fat‐saturated 3D T2* GRE and short inversion recovery sequences. Image acquisition took approximately 1 h. Results: Abnormalities of the distal interphalangeal joint (DIP) cartilage and /or subchondral bone, periarticular osteophyte formation, distension of the DIP joint capsule with or without synovial proliferation, distension of the navicular bursa with or without evidence of chronic inflammation, surface and core lesions in the deep digital flexor tendon, abnormal signal within the navicular bone, evidence of mineralised fragments in the distal sesamoidean impar ligament, irregular outline of and signal in the medial cortex of the distal phalanx, and an abnormal signal on the dorsal aspect of the distal phalanx consistent with laminitis were identified. Conclusions: MRI permits the diagnosis of a variety of lesions involving different structures within the foot that cannot be diagnosed using other means, thus enhancing our knowledge of the causes of foot pain. Potential relevance: With further experience it is likely that lesions involving other structures will also be identified. Long‐term follow‐up data is required to determine the prognosis for the injuries described.
Detection of EHV‐1 and EHV‐4 in placental sections of naturally occurring EHV‐1‐ and EHV‐4‐related abortions in the UK: use of the placenta in diagnosis
Authors: GERST S. , BORCHERS K. , GOWER S. M. , SMITH K. C. 
Published: April 2007

SummaryReasons for performing study: EHV‐1 and EHV‐4 abortion diagnosis is based upon detailed examination of the aborted fetus. However, in some cases, only the placenta is available for examination. Furthermore, the contribution of lesions in the placenta to pathogenesis and diagnosis of EHV‐1 and EHV‐4 abortion has been neglected.Objectives: To assess the utility of placental examination in equine herpesvirus‐1 (EHV‐1) and EHV‐4 abortion diagnosis.Methods: Sections of allantochorion from 49 herpesvirus abortions were analysed by PCR,in situhybridisation and immunostaining.Results: Virus‐specific nested PCR confirmed the presence of viral DNA in 46 cases; 41 cases were EHV‐1‐positive and 5 EHV‐4‐positive. Microscopic changes were nonspecific. Examination of the PCR‐positive sections of allantochorion revealed EHV‐1 DNA byin situhybridisation (ISH) in 21 cases and EHV‐4 in 4 cases. In 2 samples, DNA of both viruses was present on PCR and ISH. Viral antigen was found by immunohistology in 15 cases. Regarding the localisation of virus in the placentae, both viral DNA and antigen of EHV‐1 and EHV‐4 were found in endothelial cells of chorionic villi and, occasionally, in trophoblast epithelium. In the stromal endothelium, only EHV‐1 was found.Conclusions: The data indicate that examination of placentae is a useful diagnostic aid in EHV‐1 and EHV‐4 abortion diagnosis.Potential relevance: Virological examination of the placenta should be come standard practice in equine abortion investigations, particularly in those cases where the fetus is not available for examination.
Effects of lipopolysaccharide and phenylbutazone on gastric contents in the horse
Authors: DOHERTY T. J. , ANDREWS F. M. , BLACKFORD J. T. , ROHRBACH B. W. , SANDIN A. , SAXTON A. M. 
Published: April 2007

SummaryReasons for performing study: Endotoxaemia causes a disruption of gastrointestinal motility in the horse but there is no information on its effects on gastric secretion. Lipopolysaccharide (LPS) administration is known to affect gastric secretion in other species.Hypothesis: That LPS, a toxic component of Gram‐negative bacteria, would reduce gastric acid secretion and that pretreatment with phenylbutazone (PBZ) would block the effects of LPS.Methods: The effects of LPS and PBZ on gastric contents were investigated in fasted, mature horses, with permanent gastric cannulae. Horses were pretreated with either saline or PBZ 15 mins before a 60 min infusion of either LPS or saline. Gastric contents were collected at 15 min intervals for 3 h, beginning 15 mins after the start of the LPS or saline infusion.Results: Lipopolysaccharide significantly decreased gastric acid output, [K+] and potassium output and increased [Na+] and sodium output. Phenylbutazone did not affect basal gastric acid secretion but decreased LPS‐induced changes in the secreted volume, [Na+] and sodium output.Conclusions: This study provides evidence that LPS affects gastric acid secretion in the horse and that these LPS‐induced changes are mediated, in part, by prostaglandins.Potential relevance: Lipopolysaccharide administration can induce changes in the composition of gastric contents in the horse but further work is needed to determine the source of these changes.
Dynamic compressive strain inhibits nitric oxide synthesis by equine chondrocytes isolated from different areas of the cartilage surface
Authors: WISEMAN M. , HENSON F. , LEE D. A. , BADER D. L. 
Published: April 2007

Summary Reasons for performing study: Chondrocytes within articular cartilage respond to the mechanical stresses associated with normal joint loading via a series of signalling pathways. Specific biomolecules, such as nitric oxide (NO), have been implicated in these mechanotransduction processes. It has been shown that the synthesis of NO can be inhibited by dynamic compressive strain of chondrocytes in vitro which, in turn, leads to an up‐regulation of specific metabolic parameters. Hypothesis: Chondrocytes isolated from different joint locations and seeded in agarose constructs respond in a distinct manner to the application of dynamic compression. Methods: Chondrocytes were isolated separately from the equine patella groove and the femoral condyle, representing high loaded areas (HLA) and low loaded areas (LLA), respectively, of 6 specimens of different ages. The cells were seeded in agarose constructs and cultured either in an unstrained state or strained under dynamic loading at 1 Hz for 48 h. The synthesis of nitric oxide (NO), proteoglycan synthesis and chondrocyte proliferation were assessed. Results: Equine chondrocytes were found to synthesise significant basal levels of NO, regardless of topographical origin or age of tissue. Marked differences in both proteoglycan synthesis and cell proliferation were, however, revealed between the 2 chondrocyte subpopulations. Dynamic compression inhibited NO synthesis but significant alterations in proteoglycan synthesis and cell proliferation were apparent in a minority of cases. Conclusions and potential relevance: The differential response of the subpopulations of chondrocytes derived from the HLA and LLA provides a potential mechanism which enables the biomechanical demands of differing joint regions to be maintained.
Ultrasonography of the equine cervical region: a descriptive study in eight horses
Authors: Berg L. C. , Nielsen J. V. , Thoefner M. B. , Thomsen P. D. 
Published: April 2007

Summary Reasons for performing study: In equine patients, the cause of clinical signs possibly related to the cervical region is often difficult to diagnose. Ultrasonography allows quick and noninvasive visualisation, but reference material of the normal equine neck is needed. Objectives: To describe and document the normal ultrasonographic appearance of transverse scans in the cervical region with emphasis on the synovial articular facet joints, cervical vertebrae and paravertebral structures; and further, to provide images of frozen cross‐sections for anatomical reference. Methods: A study describing the normal ultrasonographic appearance of the cervical anatomy was performed. Transverse scans were obtained from second cervical vertebra (C2) to first thoracic vertebra (T1). Post mortem photographs of frozen cross‐sections were obtained as anatomical reference. Results: The structures were clearly visualised by ultrasonography and consistency was found between ultrasonographic images and corresponding cross‐sectional anatomy. The articular facets varied between horses and facets (C2 to T1). Discrepancy in the existing anatomical descriptions was found. Conclusions and potential relevance: The anatomical and ultrasonographic description provides a reference for ultrasonographic evaluation of equine cervical facet joints, vertebrae and paravertebral structures. The findings and variations found are considered to reflect the naturally occurring variations in horses.
Evaluation of in vitro properties of di‐tri‐octahedral smectite on clostridial toxins and growth
Authors: Weese J. S. , Cote N. M. , Degannes R. V. G. 
Published: April 2007

SummaryReasons for performing study: Clostridial colitis and endotoxaemia of intestinal origin are significant causes of morbidity and mortality in horses. Intestinal adsorbents are available for treatment of these conditions; however, little information exists supporting their use.Objectives: To evaluate the ability of di‐tri‐octahedral smectite to bind toClostridium difficiletoxins A and B,C. perfringensenterotoxin and endotoxin, inhibit clostridial growth and the actions of metronidazolein vitro.Methods: Clostridium difficiletoxins,C. perfringensenterotoxin and endotoxin were mixed with serial dilutions of di‐tri‐octahedral smectite, then tested for the presence of clostridial toxins or endotoxin using commercial tests. Serial dilutions of smectite were tested for the ability to inhibit growth ofC. perfringensin culture broth, and to interfere with the effect of metronidazole on growth ofC. perfringensin culture broth.Results: Clostridium difficiletoxins A and B, andC. perfringensenterotoxin were completely bound at dilutions of 1:2 to 1:16. Partial binding ofC. difficiletoxins occurred at dilutions up to 1:256 while partial binding ofC. perfringensenterotoxin occurred up to a dilution of 1:128. Greater than 99% binding of endotoxin occurred with dilutions 1:2 to 1:32. No inhibition of growth ofC. difficileorC. perfringenswas present at any dilution, and there was no effect on the action of metronidazole.Conclusions: Di‐tri‐octahedral smectite possesses the ability to bindC. difficiletoxins A and B,C. perfringensenterotoxin and endotoxinin vivowhile having no effect on bacterial growth or the action of metronidazole.Potential relevance: In vivostudies are required to determine whether di‐tri‐octahedral smectite might be a useful adjunctive treatment of clostridial colifis and endotoxaemia in horses.
Meniscal tears in horses: an evaluation of clinical signs and arthroscopic treatment of 80 cases
Authors: WALMSLEY J. P. , PHILLIPS T. J. , TOWNSEND H. G. G. 
Published: April 2007

Summary Reasons for performing study: There is little published information available describing clinical signs, arthroscopic findings and prognosis of meniscal injuries in horses. Objectives: To evaluate the effect on the outcome not only of the arthroscopic findings and treatment, but also of the clinical and radiographic signs in these horses. Methods: The following were recorded for each case: the meniscal injury, graded according to severity; clinical and radiographic findings prior to surgery; any concurrent injury in the joint seen at arthroscopy. The effect of these factors and the grade of injury on the outcome were analysed using Fisher's exact test or Chi‐square analysis. Only horses whose meniscal injury was judged to be the primary cause of lameness were included in the series. Results: A series of 80 meniscal injuries were diagnosed and treated arthroscopically by the authors at the Liphook Equine Hospital and 47% of horses returned to full use. Statistically, poor prognosis was associated with increasing severity of the meniscal injury, the presence of concurrent articular cartilage lesions and radiographic abnormalities in the joint. Arthroscopic treatment of many lesions was limited by the inaccessibility of parts of the femorotibial joint. Potential relevance: Further work is required to improve and evaluate arthroscopic techniques for the treatment of these injuries.
Radiographic changes in Thoroughbred yearlings. Part 1: Prevalence at the time of the yearling sales
Authors: KANE A. J. , PARK R. D. , McILWRAITH C. W. , RANTANEN N. W. , MOREHEAD J. P. , BRAMLAGE L. R. 
Published: April 2007

SummaryReasons for performing study: Radiography in presale examinations of TB yearlings has become standard practice in recent years.Objectives: To describe the prevalence and distribution of radiographic changes in the fetlocks, carpi, tarsi, stifles and fore feet of Thoroughbred yearlings in central Kentucky when these joints were examined as part of routine pre‐ and post sale evaluations.Methods: Horses subjected to radiographs included the fore (n = 1127) and hind (n = 1102) fetlocks, carpi (n = 1130), tarsi (n = 1101), stifles (n = 660) and fore feet (n = 300). Radiographic changes were categorised by location and type of change present (e.g. lucency, fragment) for each series.Results: In the fore fetlocks 1.6% had fragmentation of the proximal dorsal first phalanx and 0.5% fragmentation of the proximal palmar aspect. In the hind fetlocks 5.9% had fragmentation at the plantar aspect and 3.3% fragmentation dorsally. Lucencies, fragments or loose bodies were detected at the dorsal aspect of the distal third metacarpus in 2.8% and, at the same location on the third metatarsus, 3.2%. Most yearlings (98%) had vascular channels in the proximal sesamoid bones and irregularvascular channels (>2 mm wide or with nonparallel sides) were more common (79%) than regular vascular channels (56%). The intermediate ridge of the distal tibia was the most common location for fragmentation in the tarsus (4.4%).Conclusions: While some radiographic changes, e.g. vascular channels in proximal sesamoid bones, are very common in Thoroughbred yearlings, others, e.g. fragmentation or subchondral lucency within joints are quite rare usually affecting less than 5% of the population.Potential relevance: Veterinarians should expect to find radiographic changes in Thoroughbreds presented for examination prior to the yearling sales. The rarity of some changes thought to affect soundness or racing performance will make further invesigation of these conditions in horses without clinical signs more difficult.
Prolonged suppression of the innate immune system in the horse following an 80 km endurance race
Authors: ROBSON P. J. , ALSTON T. D. , MYBURGH K. H. 
Published: April 2007

SummaryReasons for performing study: An increased susceptibility to bacterial and viral infections of the respiratory tract, which results in a loss of performance, has been reported in racehorses. Much research has focused on the influence of high‐intensity exercise of a short duration on immune system function in horses, but scant attention has been given to prolonged endurance exercise as an immune modulator.Objectives: The objective of this study was to evaluate the effect of an 80 km endurance race on the monocyte and neutrophil oxidative burst, serum Cortisol, glutamine and plasma glucose concentrations in 8 endurance‐trained horses (mean ± s.d. age 9.4 ± 2.2 years).Methods: Blood samples were drawn from the horses prior to and following an 80 km ride.Results: Mean time for completion of the 80 km race was 306 ± 40 mins. Immediately post race mean serum Cortisol concentration, blood monocyte and neutrophil counts were higher and blood lymphocyte counts and plasma glucose concentration were lower compared with prerace values (P<0.05). Neutrophil and monocyte oxidative burst activity decreased following the race and had not regained prerace values after 3 days of rest (P<0.05).Conclusions: The present study indicates that long duration exercise in horses has a negative impact on the function of the innate immune system that lasts several days post race. Precise mechanisms instigating the fall in innate immune system function are unclear and multifactorial, but may be attributed, at least in part, to a high serum Cortisol response during very prolonged exercise.Potential clinical relevance: A prolonged bout of exercise results in a long‐term suppression of the innate immune system function in horses which may, in part, account for the observed increase of infectious episodes in horses during training.