bluuebunny/crossref_metadata_2025_split huggingface dataset:
Equine synovial tendon sheaths and bursae: an histological and scanning electron microscopical study
Authors: HAGO B. E. D. , PLUMMER J. M. , VAUGHAN L. C. 
Published: April 2010

SummaryThe structure of equine synovial tendon sheaths and bursae has been examined by light and scanning electron microscopy. Tissue samples were obtained from horses of various types and ages with no clinical evidence of sheath or bursal disorders. The interior of both structures was lined by a cellular layer superimposed on a vascular zone supported by a fibrous layer. The pattern of cell distribution of the lining varied from site to site within the same structure depending on the nature of the underlying tissue and on the amount of movement to which the structure was subjected. The cellular layer was predominantly fibrous in nature with scanty, widely separated fibroblasts (eg where it lines the palmar ligament, tendons and paratendons). In the mesotendon and bursal extremities, where the lining is subjected to a positive degree of movement, the cellular layer was areolar in type with well established folds populated by abundant cells oval to round in shape. In foals and yearlings, the supportive layer was mainly around the areolar with patches of adipose tissue; which were gradually replaced by fibrous tissue as the animal grew.
Ultrastructural findings in horses with chronic obstructive pulmonary disease (COPD) I: alterations of the larger conducting airways
Authors: KAUP F.‐J. , DROMMER W. , DEEGEN E. 
Published: April 2010

SummaryExtensive light and electron microscope studies of the conducting airways were carried out in 28 horses with varying degrees of clinically manifested chronic obstructive pulmonary disease (COPD) and in 8 horses with normal lungs. The principal ultrastructural changes were found in the ciliated cells. There was focal loss of ciliated cells, which were replaced by undifferentiated cells in a largely hyperplastic epithelium, and some horses, independent of the degree of severity of the disease, showed various types of ciliary malformation. The finding of dilated intercellular clefts and accumulations of mast cells was interpreted as morphological evidence of non‐specific mucosal hyperreactivity. Interstitial cells with intracytoplasmal crystal inclusions, the cause of which is not clear, were seen in many horses. Comparison between the clinical diagnosis and the morphological findings showed partial correlation. The ciliary loss, the appearance of peribronchial inflammatory processes and the occurrence of intracytoplasmic crystalline inclusions showed a positive correlation. In 12 of 28 cases, the severity of clinical diagnosis agreed with the degree of the morphological findings. The changes in the conducting airways were interpreted pathogenetically as reactive processes to changes in the small airways in the course of equine COPD.
Peritoneal fluid values from healthy foals
Authors: GRINDEM C. B. , FAIRLEY N. M. , UHLINGER C. A. , CRANE S. A. 
Published: April 2010

SummaryPeritoneal fluid was analysed from 17 foals, aged 13 to 134 days with a mean age of 68 days. Cytologically, the peritoneal fluid was characterised by a mean total cell count of 0.45 times 109/litre (range 0.06 to 1.42 times 109/litre), rare eosinophils, rare cytophagia and variable percentages of neutrophils and mononuclear cells. These data indicate that peritoneal fluid nucleated cell counts over 1.50 times 109/litre in the foal should be interpreted as elevated. Biochemical evaluation revealed a mean biuret protein level of 12 g/litre, mean refractive index protein level of 16 g/litre and urea nitrogen concentration of 1.96 mmol/litre. There was no correlation between the foals' white blood cell and peritoneal fluid nucleated cell counts. Results of this study indicate that adult horse reference values for evaluation of peritoneal fluid are of questionable validity for foals. Diagnostically, the most important observation was that maximum peritoneal fluid nucleated cell counts in healthy foals were much lower than reported maximal reference values for adult horses (1.5 times 109/litre versus 5.0 times 109/litre or 10.0 times 109/litre).
Left ventricular volume determination in the horse by two‐dimensional echocardiography: anin vitrostudy
Authors: VÖRÖS K. , HOLMES J. R. , GIBBS CHRISTINE 
Published: April 2010

SummaryThis study was designed to evaluate the accuracy of two‐dimensional echocardiography (2DE) in determining the left ventricular volume (LVV) of the horsein vitro.After examining the shape of the left ventricular silicon rubber casts of four equine hearts, two modified Simpson's rule methods (Model A and Model B) as combinations of conical shapes and one biplane area‐length method as a single cone (Model C) were chosen for volume calculations. One long axis and three short axis planes were used for linear and area 2DE measurements, respectively. The ventricular length (L) was calculated from the chordal length (CL) by using a linear regression equation (L = 5.54 + 1.83 CL) obtained by anatomical measurement of these two parameters on 40 normal hearts. The LVV was calculated in 15 formalin‐fixed hearts from 2DE measurements with the three geometric models. Left ventricular casts were then made using silicon rubber, and their volumes were determined by water displacement. The calculated volumes were plotted against cast volumes with linear regression analysis. All calculated LVVs correlated well with the cast LVVs (R = 0.921 to 0.957; P<0.001). The highest correlation was provided by Model A which best represented the shape of the left ventricle. This model consisted of a truncated cone bordered by the area at the level of the mitral valve and by the area at the level of the chordae tendineae, plus a cone the base of which was the area at the level of the papillary muscles. The results demonstrate the applicability of 2DE for equine LVV determinationsin vitro, similar to other species. The method requires further investigation in the living horse.
Effects of five hours of constant 1.2 MAC halothane in sternally recumbent, spontaneously breathing horses
Authors: STEFFEY E. P. , WOLINER M. J. , DUNLOP C. 
Published: April 2010

SummaryCirculatory and respiratory effects of five h of constant 1.06 per cent alveolar halothane in oxygen were identified in eight healthy horses, which breathed spontaneously, were otherwise unmedicated and positioned in sternal recumbency. Only a few important significant (P<0.05) changes occurred with time. Total peripheral resistance was about 15 per cent lower after two hours of constant dose halothane than after 30 mins of constant dose (P<0.05) and accounted for the significant 10 per cent reduction in mean carotid arterial blood pressure. By 5 h, the reduction in resistance and arterial blood pressure was 20 and 25 per cent respectively. Heart rate increased progressively with time and the increase became significant at 5 h (15 per cent increase). However, the heart rate change was not large enough to alter cardiac output. There were no major time‐related changes in PaO2or PaCO2. Three of four horses recovered from anaesthesia had markedly elevated serum creatine kinase levels and clinical signs of severe post anaesthetic myopathy.
Cranial thoracic masses in the horse: a sequel to pleuropneumonia
Authors: BYARS T. D. , DAINIS C. M. , SELTZER K. L. , RANTANEN N. W. 
Published: April 2010

SummaryThe formation of cranial thoracic masses (CTM) as a sequel to infectious pleuropneumonia is described. Using ultrasound, masses were diagnosed subjectively as abscesses or loculations. Eight of 99 cases with pleuropneumonia had CTM. Clinical signs associated with the presence of a CTM included increased heart rate, jugular distention, forelimb ‘pointing’ and caudal displacement of the heart. Techniques used for diagnostic ultrasonographic examination of the cranial thorax are described. Five of the eight horses with CTM responded to conservative medical management; the other three required percutaneous drainage of the mass to relieve worsening signs of cardiac decompensation. Improvements in cardiovascular parameters were evident within 12 h of drainage. The indications for and limitations of invasive drainage of cranial thoracic masses are discussed.
The use of the walking cast to repair fractures in horses and ponies
Authors: NÉMETH F. , BACK W. 
Published: April 2010

SummaryThe walking cast was used to repair 46 fractures of long bones (distal radius and tibia, metacarpus and metatarsus) and 10 fractures of first phalanx of 35 horses and 21 ponies. The walking cast proved to be highly effective. Even heavily comminuted and ‘hopeless' fractures, which could not be treated with osteosynthesis, were treated successfully, because the weight of the animal, a common failure factor in large animal orthopaedics, was relieved from the injured leg. Immediate full weight bearing was possible post operatively. In five cases the walking cast was used in combination with osteosynthesis. Infection was the main complication that caused the walking cast to fail. Osteomyelitis may also be treated with a walking cast. Because of its success rate of 57 per cent, which is impressive, considering the type of fractures treated, we recommend the walking cast for international accreditation.
A comparison of techniques to enhance the evaluation of equine laryngeal function
Authors: ARCHER R. M. , LINDSAY W. A. , DUNCAN I. D. 
Published: April 2010

SummaryThis study was designed to define a simple, unequivocal test for the evaluation of laryngeal function and the diagnosis of idiopathic laryngeal hemiplegia (ILH). ILH is a disorder that results from left recurrent laryngeal neuropathy and in which there is no movement of the left arytenoid cartilage and vocal fold. Laryngeal function was evaluated in seven horses using four techniques designed to stimulate laryngeal movements:‐nasal occlusion, exercise, swallowing and administration of a respiratory stimulant. In addition, the effects of sedation and twitching on the endoscopic examination were also examined. The cross‐sectional area of the rima glottidis was measured in each horse at rest and after each technique was performed. There was no statistically significant difference in the increase in area seen after nasal occlusion or exercise. Doxapram hydrochloride increased the cross‐sectional area of the rima glottidis, whereas xylazine caused a decrease. Neither of these pharmacological agents exaggerated or decreased the amount of asynchronous movement or tremoring of the arytenoid cartilages. Manual occlusion of the external nares during endoscopy is a simple, yet effective method of stimulating arytenoid function and hence diagnosing ILH.
The raising of equine colostrum‐deprived foals; maintenance and assessment of specific pathogen (EHV‐1/4) free status
Authors: CHONG Y. C. , DUFFUS W. P. H. , FIELD H. J. , GRAY D. A. , AWAN A. R. , O'BRIEN M. A. , LUNN D. P. 
Published: April 2010

SummaryOver a period of two years, a total of 22 full term foals from Welsh Mountain pony mares were raised in conditions that were free from infection by Equid herpesvirus (EHV‐1/4). Parturition dates were predicted by monitoring colostrum electrolytes, and the mares allowed to foal naturally under supervision or following induction with intravenous oxytocin. Immediately following birth, foals were separated from their dams and transferred to a specially built, positive pressure isolation unit. They were given antibiotic prophylaxis and fed bovine colostrum during the first 24 h, and then mare's milk replacer until weaned. Out of 22 specific pathogen free (SPF) foals one that had not been given antibiotic prophylaxis died of anE. colisepticaemia aged eight days. Two foals developed a streptococcal upper respiratory tract infection, which responded to antibiotic therapy and did not spread to the rest of the herd. A self limiting upper respiratory tract infection was seen in a fourth foal and mild diarrhoea was observed in six foals. Physical development in all SPF foals appeared normal and behavioural patterns resembled those of conventional hand‐reared foals. Newborn foals were held in a separate quarantine area, within the isolation unit, and checked extensively for evidence of EHV‐1/4 infection, before being transferred to the main holding unit. Periodic checks were then made for EHV‐1/4 over a period ranging from 2 to 4 months; none of the SPF foals showed evidence of infection with EHV‐1/4 in terms of clinical disease, virus isolation, sero‐conversion or specific lymphocyte transformation.
A study of bovine and equine immunoglobulin levels in pony foals fed bovine colostrum
Authors: HOLMES M. A. , LUNN D. P. 
Published: April 2010

SummaryAs part of a project to raise specific pathogen free (SPF) Welsh Mountain Pony foals, free from exposure to Equid herpesvirus type 1, foals were removed from their dams at birth and fed bovine colostrum. This study characterises the uptake of bovine colostral immunoglobulin and production of endogenous immunoglobulin, in 10 SPF foals. An enzyme‐linked immunoadsorbant assay was developed to measure serum concentrations of bovine IgG1(boIgG1) to assess the efficiency of transfer, and rate of elimination of boIgG1by the foal. The endogenous production of equine IgG was studied using a single radial immunodiffusion test Foals were given 1.2 to 2 litres of bovine colostrum achieving peak serum boIgG1concentrations of 18.9 to 34.2 g/litre (mean 28.0). The mean half‐life of boIgG1in the foals was 7.4 days. Endogenous immunoglobulin production resulted in equine IgG concentrations >2 g/litre in six of 10 foals by 14 to 19 days of age, and >6 g/litre in eight of 10 foals by 37 to 50 days of age. All foals had equine IgG serum concentrations >10 g/litre by 102 to 135 days of age.
Maternal and umbilical venous plasma lipid concentrations at delivery in the mare
Authors: STAMMERS J. P. , HULL D. , LEADON D. P. , JEFFCOTT L B. , ROSSDALE P. D. 
Published: April 2010

SummaryThe concentrations and fatty acid composition of the plasma free fatty acid, triacylglycerol and phospholipid fractions were determined in maternal and umbilical cord vein blood samples taken at delivery from 17 mares. Maternal and umbilical vein plasma free fatty acid concentrations were of a similar order and a positive correlation was found between the two levels suggesting that the equine placenta is permeable to fatty acid. Substantial amounts of the essential fatty acids and their longer chain derivatives were seen in both umbilical vein plasma free fatty acid and phospholipid fractions supporting this view. Certain long chain polyunsaturated derivatives of the essential fatty acids found in the umbilical venous plasma phospholipid fraction were not seen in the maternal circulating lipids. The precursor fatty acids were readily available to both foetal and placental tissues and therefore must have been elongated and incorporated into phospholipid by either or both. Very small amounts of the essential fatty acids were found in adipose stores in the newborn foal and virtually no fat stores at all in the newborn foal liver.
Lameness due to pain associated with the distal interphalangeal joint: 45 cases
Authors: DYSON SUE J. 
Published: April 2010

SummaryThis paper describes the clinical and radiographic features, and response to treatment, of 45 horses which showed lameness that was improved by intra‐articular anaesthesia of the distal interphalangeal (DIP) joint. Although many horses had poor conformation of the foot of the lame limb, the majority showed no localising clinical signs suggestive of involvement of the DIP joint. Lameness was usually unilateral. No horse with bilateral lameness responded to treatment. Palmar digital nerve blocks frequently improved or alleviated lameness, although in some horses palmar (abaxial sesamoid) nerve blocks were required to eliminate lameness. This difference in response did not affect response to treatment. Intra‐articular anaesthesia of the DIP joint usually resulted in resolution of lameness within 5 mins; a partial improvement in lameness or a slow response were poor prognostic indicators. None of the horses had radiographic abnormalities compatible with navicular disease. Radiographic changes of the distal interphalangeal joint per se were generally detectable only in lateromedial views and were identified in less than one third of the horses. Success rates were low following treatment of cases with radiographic abnormalities. In those with no radiographic abnormalities the response to corrective trimming and shoeing and intra‐articular administration of sodium hyaluronate, once or repeatedly, was variable and no parameters could be used to predict the likely outcome. Treatment was successful in approximately 30 per cent of cases. Subsequent treatment of horses which remained lame, by intraarticular administration of polysulphated glycosaminoglycans, was not helpful; only a small proportion became sound following prolonged (nine months) rest. The overall poor success rate of treatment and the results of post mortem examination of three horses which failed to respond to treatment, demonstrated the limitations of radiographic evaluation of this area. More importantly, it is still not clear which structures can be affected by intra‐articular anaesthesia of the DIP joint.
Comparison of yearling, two‐year‐old and adult Thoroughbreds using a standardised exercise test
Authors: SEEHERMAN HOWARD J. , MORRIS ELISABETH A. 
Published: April 2010

SummaryThe purpose of this study was to compare exercise measurements in yearling, two‐year‐old and adult Thoroughbreds using a standardised treadmill incremental exercise test. Peak oxygen consumption (V̇O2peak: 128.0 ± 2.1, 140.0 ± 2.1, 163.7 ± 3.4; ml/kg/min ± se, P<0.05), peak packed cell volume (PCVpeak: 0.50 ± 0.01, 0.58 ± 0.01, 0.64 ± 0.01litres/litre ± se, P<0.05) and the maximum number of steps completed in the exercise test (STEPmax: 7.7 ± 0.1, 8.1 ± 0.1, 8.6 ± 0.1; steps ± se, P<0.05) increased with age and degree of physical activity. Peak venous lactate concentration (LACpeak: 21.3 ± 1.5, 19.5 ± 1.7, 14.4 ± 1.7; mmol/litre ± se, P<0.05) and peak respiratory exchange ratio (Rpeak) were significantly higher in both groups of younger horses compared to the adult racehorses. Peak heart rate (HRpeak: 230 ± 2, 231 ± 3, 229 ± 3; beats/min ± se) did not change with age or training. The rate of change of V̇O2between steps in the exercise test (V̇O2trans) was significantly lower in the adult racehorses at the highest exercise intensities. The slopes of the linear approximation between R (LinR bx), the natural log transformation of venous lactate concentration (LogLAC bx), and heart rate (HR bx) with velocity were significantly lower in the trained adult racehorses. The slope of venous lactate concentration normalised to per cent V̇O2peak (LogLAC per cent bx) was significantly lower and R breakpoint (R brkpt) normalised to per cent V̇O2peak was significantly higher in the trained adult racehorses. There was a more rapid decrease in venous lactate and a more rapid return to initial R values in the adult horses relative to the younger, untrained horses. No significant age or training effects were found in the remainder of the post exercise measurements. These results indicate that aerobic power and exercise capacity increased with age and training. Anaerobic power was already well developed even at a young age.
Titrimetric determination of muscle buffering capacity (βmtitr) in biopsy samples
Authors: MARLIN D. J. , HARRIS R. C. 
Published: April 2010

Summary In vitro titration of muscle homogenates has been used to assess muscle buffering capacity (βmtitr) in a variety of species. In the present study, factors likely to affect the estimation of βmtitr were investigated. Also, values of βmtitr from normal Thoroughbred horses are presented. A non‐linear titration curve was obtained with addition of HCl to muscle homogenates. As a result, βmtitr is expressed as the μmol H+ required to change the pH of 1g of dry muscle or wet muscle from 7.1 to 6.5. An effect of dilution on the initial pH was found below 40 mg wet muscle per ml homogenising reagent (10 mg dry muscle per ml) and on βmtitr below 10 mg wet muscle. As a result, 40 mg wet muscle or 10 mg dry muscle per ml was chosen as the minimum concentration for determination of βmtitr. Incubation of homogenates up to 60 mins did not affect βmtitr significantly. As a mean, βmtitr in wet muscle was approximately 25 per cent higher compared to dry muscle. The βmtitr of dry muscle was increased by approximately 18 per cent when HCO3− was added in an amount equivalent to the calculated HCO3− content of wet muscle at rest. The homogenisation process resulted in complete loss of adenosine triphosphate and phosphocreatine with only small changes in adenosine diphosphate and adenosine monophosphate. It was concluded that the estimates of βmtitr did not include any contribution from ‘dynamic’ buffering via rephosphorylation of adenosine diphosphate by phosphocreatine, and in dry muscle it was accounted for mainly through physico‐chemical buffering by phosphates, proteins and dipeptides. βmtitr determined in biopsy samples of muscle from 20 Thoroughbred horses ranged from 100.8 to 131.8 μmol H+/g dry muscle pH 7.1 to 6.5 (mean 121.2, sd ± 7.4).
Muscle characteristics in Thoroughbreds of different ages and sexes
Authors: RONËUS M. , LINDHOLM A. , ÅSHEIM Å. 
Published: April 2010

SummaryMuscle biopsies were taken from the middle gluteal muscle in 163 healthy Thoroughbreds aged one to six years. The horses were separated according to sex and divided into four different age groups (one, two, three and four to six years). Muscle biopsies were analysed for fibre type (I, IIA and IIB), and the enzyme activities of citrate synthase, 3‐OH‐acyl‐CoA dehydrogenase, lactate dehydrogenase and hexokinase were measured. The percentage of Type I fibres of all horses increased with age, irrespective of sex (from 9 to 16 per cent). The percentage of Type IIA fibres varied with age and sex, increasing in stallions from 34 to 53 per cent and in mares from 27 to 45 per cent, respectively. Correspondingly, the proportion of Type IIB fibres decreased with age and differed between sexes (stallions from 56 to 29 per cent and mares from 65 to 40 per cent). Muscle oxidative capacity increased with age as indicated by significant increases in the activities of citrate synthase (from 32 to 67 mmol/kg/min) and 3‐OH‐acyl‐CoA dehydrogenase (from 20 to 34 mmol/kg/min). The activity of hexokinase increased with age (from 2.4 to 4.8 mmol/kg/min), whereas the activity of lactate dehydrogenase decreased (from 1,754 to 1,444 mmol/kg/min). No differences were seen between stallions and mares in enzyme activities. This study shows that age is one factor influencing enzyme activities, the percentage of Type I fibres and the Type IIA/IIB ratio in M. gluteus medius of Thoroughbreds, and that stallions have a higher Type IIA/IIB ratio compared with mares.
Prevalence of serum precipitating antibodies in horses to fungal and thermophilic actinomycete antigens: effects of environmental challenge
Authors: MADELIN T. M. , CLARKE A. F. , MAIR T. S. 
Published: April 2010

SummarySera from 54 two‐ to three‐year‐old Thoroughbred horses from an English racing stable were examined for precipitins to antigen extracts prepared from 18 species of moulds (fungi and thermophilic actinomycetes) isolated from the same stable. Twenty‐seven horses exhibited serum precipitins to one or more antigens; sixteen of the mould antigens elicited positive reactions in sera from one or more horses. Significantly more precipitins occurred in sera of those horses stabled in a barn than among those stabled in individual boxes. This indicated a possible association between type of housing, level of exposure to airborne moulds and presence of serum precipitins. None of the horses had overt respiratory disease. This study agrees with reports of the presence of serum precipitating antibodies to mould antigens in clinically healthy horses and confirms that serological tests, therefore, are of little value in the diagnosis of chronic obstructive pulmonary disease (COPD) or ‘heaves’.