bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of IgG and IgE serum antibodies to Culicoides salivary gland antigens in horses with insect dermal hypersensitivity (sweet itch)
Authors: WILSON A. D. , HARWOOD L. J. , BJÖRNSDOTTIR S. , MARTI E. , DAY M. J. 
Published: April 2007

SummaryWe postulated that all horses exposed to the bites of Culcoides (midges) would have an antibody response to the antigen secreted in Culcoides saliva, but that IgE antibody would be restricted to allergic individuals. Using immunohistology on sections of fixed Culicoides, we have demonstrated the presence of antibodies in horse serum which recognise Culicoides salivary glands. Antibodies were detected in the serum of horses with insect dermal hypersensitivity and in the serum of normal horses exposed to Culicoides bites. In contrast, no antibodies were detected in serum from native Icelandic ponies which had not been exposed to Culicoides. Anti‐salivary gland IgG antibodies were detected in serum from both allergic and healthy horses exposed to Culicoides. IgE antibodies were only detected in horses with signs of insect dermal hypersensitivity, they were not found in serum of healthy controls nor in the serum of horses with a history of hypersensitivity but in remission at the time of sampling. Using western blotting we confirmed the presence of antibodies to Culicoides antigens and demonstrated that individual horses react to different numbers of antigens. This paper demonstrates the ability of serum from allergic horses to detect Culcoides antigens and will enable further studies to isolate and characterise the allergens.
Passive transfer of maternal immunoglobulin isotype antibodies against tetanus and influenza and their effect on the response of foals to vaccination
Authors: WILSON W. D. , MIHALYI J. E. , HUSSEY S. , LUNN D. P. 
Published: April 2007

SummaryInfluenza and tetanus‐specific antibodies of the IgG sub‐isotypes are posively transferred to foals via colostrum and inhibit their response to inactivated influenza vaccines and tetanus toxoid. High titres of influenza antibodies of IgGa and IgGb subisotypes and tetanus antibodies of the IgGa, IgGb and IgG(T) subisotypes were detected in postsucking serum samples collected from foals born to mares that had received booster doses of multicomponent vaccines during the last 2 months of gestation. Thereafter, titres declined in an exponential manner but were still detectable in all foals at age 26 weeks, regardless of whether they had been vaccinated prior to age 26 weeks. Mean ± s.e. half‐life of decline of influenza IgGa antibodies (27.0 ± 2.3 days) was significantly shorter than that of influenza IgGb antibodies (39.1 ± 2.7 days; P<0.005). Tetanus IgGa and IgGb antibodies declined with half‐lives of 28.8 ± 3.0 and 34.8 ± 5.1 days, respectively. Titres of tetanus IgG(T) antibodies were substantially higher than those of influenza IgG(T) antibodies in postsucking samples and remained so through age 26 weeks, declining with a half‐life of approximately 35 days. Postsucking titres of tetanus and influenza antibodies of the IgA isotype were low and declined rapidly to undetectable levels.Yearlings showed significant increases in titre of influenza IgGa, IgGb and IgG(T) subisotype antibodies but no increase in influenza IgA antibodies in response to 2 doses of multicomponent vaccines containing tetanus toxoid and inactivated influenza A‐1 and A‐2 antigens. Yearlings also showed strong tetanus IgGa, IgGb and IgG(T) subisotype responses to one dose of vaccine and a substantial further rise in titre in response to administration of a second dose 3 weeks later, but failed to show an increase in titre of tetanus IgA antibodies. The influenza and tetanus IgGa, IgGb and IgG(T) subisotype responses of 6‐month‐old foals to vaccination followed the same pattern as those shown by yearlings but titres were generally lower. In contrast, 3‐month‐old foals failed to show increases in titre of either influenza or tetanus IgG subisotypes in response to 2 doses of vaccine and generally needed 1–3 additional booster doses of vaccine to achieve titres similar to those achieved by yearlings after 2 doses. Based on the finding that maternal antibodies exert a significant inhibitory effect on the response of foals to tetanus toxoid and inactivated influenza antigens, it is recommended that primary immunisation of foals born to vaccinated mares should not commence before age 6 months.
Endothelin in the equine hypoxic pulmonary vasoconstrictive response to acute hypoxia
Authors: BENAMOU A. E. , MARLIN D. J. , LEKEUX P. 
Published: April 2007

SummaryElevated concentrations of endothelin (ET), a potent endothelium‐derived vasoactive peptide, have been reported in a number of pathophysiological conditions associated with pulmonary hypertension, both in the horse and other species. We have previously shown, both in vitro and in vivo, that the pulmonary and systemic vascular response to exogenous ET is mediated predominantly via ETA receptors. Our hypothesis in the present study was that ET is involved in the equine hypoxic pulmonary vasoconstrictive response to acute hypoxia. In this study, we investigated the effects of a selective ETA receptor antagonist on hypoxic pulmonary hypertension in the mature horse. Horses were exposed to a 10 min period of hypoxia (FIO2∼0.11) on 2 occasions, with and without pretreatment with the selective ETA receptor antagonist TBC11251 (10 mg/kg bwt i.v.). Hypoxia increased mean pulmonary artery pressure (PAP) from 18.3 ± 0.9 (mean ± s.e. normoxia) to 28.0 ± 0.8 mmHg (hypoxia) in the session without ETA receptor antagonism. Carotid arterial pressure (CAP) also increased progressively throughout the period of hypoxic challenge and at the end was 153 ± 5 mmHg (hypoxia) compared to during normoxia (140 ± 5 mmHg). There was no significant overall effect of ETA receptor antagonism on the haemodynamic or ventilatory responses to acute hypoxia. However, between 5 and 10 min of hypoxia there was a trend for the mean PAP to diverge in the 2 treatments, which just failed to reach significance at 10 min of hypoxia (P = 0.053). In conclusion, this study describes the haemodynamic and ventilatory changes in response to a period of acute hypoxia in the adult horse. The results do not support a role for ET as a mediator of acute HPV in the horse, but suggest that it may be involved as a modulator or in the slower (>10 min) phase of HPV.
Effects of phlebotomy on haemodynamic characteristics during exercise in Standardbred trotters with red cell hypervolaemia
Authors: FUNKQUIST P. , SANDHAGEN B. , PERSSON S. G. B. , HEDENSTIERNA G. , ESSÉN‐GUSTAVSSON B. , NYMAN G. 
Published: April 2007

SummaryFive Standardbred trotters with red cell hypervolaemia (RCHV) were compared before and after removal of approximately 22% (36 ml/kg bwt) of the total blood volume in order to evaluate the haemodynamic responses, haemorheological alterations and oxygen transport during exercise to fatigue. Data were recorded during submaximal exercise at 4 different speeds on a treadmill and then during continued running at the highest speed step until fatigue. Oxygen uptake (V̇O2), pulmonary artery pressure (PAP), systemic artery pressure (SAP), heart rate (HR), haematocrit and haemoglobin concentrations (Hb) were measured. Arteriovenous O2content difference (C(a‐v̄)O2), pulmonary vascular resistance (PVR) and total systemic resistance (TSR) were calculated. Whole blood and plasma viscosity and erythrocyte aggregation tendency were determined with a rotational viscometer. Endoscopy was performed after exercise. ANOVA was used for statistical analysis.Phlebotomy resulted in a decrease in haematocrit and Hb during the course of exercise. Blood and plasma viscosity were lower and erythrocyte aggregation tendency was higher after phlebotomy. Throughout exercise, including submaximal work and continued running to fatigue, PAP, SAP, PVR, TSR and C(a‐v̄)O2were lower after phlebotomy. HR was higher after phlebotomy during submaximal exercise. Oxygen delivery and VO2were lower after phlebotomy in the period from submaximal exercise to fatigue. Run time to fatigue was shorter after phlebotomy. Four horses showed exercise‐induced pulmonary haemorrhage (EIPH) before phlebotomy and the degree of bleeding was diminished but not abolished after phlebotomy.The reductions in PVR, TSR, PAP and SAP after phlebotomy were probably a result of reduced blood viscosity. In conclusion, although a 22% reduction in blood volume improved the haemodynamic and haemorheological parameters and the degree of EIPH, it was found that RCHV trotters have to rely on high oxygen delivery to the working muscles for maintenance of maximal performance.
A cross‐sectional study of colic in horses on Thoroughbred training premises in the British Isles in 1997
Authors: HILLYER M. H. , TAYLOR F. G. R. , FRENCH N. P. 
Published: April 2007

SummaryThe aim of this study was to estimate the incidence of colic in horses in Thoroughbred training premises in 1997 in the British Isles. The seasonal pattern and outcome of colic episodes were also investigated, together with any association between premises level variables and colic. Data were collected by a postal questionnaire.The results showed a colic incidence density of 7.19/100 horse years (s.e. 0.42) and a cumulative incidence of colic of 5.80% (s.e. 0.30). Premises were grouped according to whether they had more Flat than National Hunt horses (Flat premises) or more National Hunt than Flat horses (NH premises). A similar rate of colic episodes was found in each group. However, significantly higher cumulative incidences of one episode of colic were found in the Flat premises and of multiple episodes in the NH premises, respectively. The outcome of each episode of colic showed spontaneous recovery in 28.7%, medical recovery in 63.1%, surgical recovery in 2.0% and death in 6.2% of cases. This indicated an overall mortality rate from colic of 0.45 deaths/100 horse years. The seasonal pattern of episodes of colic showed a spring and autumn peak, with significant differences in the seasonal pattern between the Flat and NH premises. Relative risk analysis and logistic regression modelling with random effects showed significant associations between the number of episodes of colic and the number of horses on the premises (allowing for the number of horses on each premises, the larger premises had a decreased risk of colic). After adjusting for the number of horses, 3 other variables were associated with colic; Flat premises (with an increased risk), the owner being the sole person looking after the horses (a decreased risk) and the premises being a combined training and breeding establishment (a decreased risk).
Recovery from transport and acclimatisation of competition horses in a hot humid environment
Authors: MARLIN D. J. , SCHROTER R. C. , WHITE S. L. , MAYKUTH P. , MATTHESEN G. , MILLS P. C. , WARAN N. , HARRIS P. 
Published: April 2007

SummaryThe aims of the present field‐based study were to investigate changes in fit horses undergoing acclimatisation to a hot humid environment and to provide data on which to base recommendations for safe transport and acclimatisation. Six horses (age 7–12 years) were flown from Europe to Atlanta and underwent a 16 day period of acclimatisation. Exercise conditions during acclimatisation (wet bulb globe temperature index 27.6 ± 0.0 [mean ± s.e.]) were more thermally stressful compared with the European climate from which the horses had come (22.0 ± 1.8, P<0.001). Following the flight, weight loss was 4.1 ± 0.8% bodyweight and took around 7 days to recover. Water intake during the day was significantly increased (P<0.05) compared with night during acclimatisation. Daily mean exercise duration was 72 ± 12 min and the majority of work was performed with a heart rate below 120 beats/min. Respiratory rate (fR) was increased (P<0.05) throughout acclimatisation compared with in Europe, but resting morning (AM) and evening (PM) rectal temperature (TREC), heart rate (fC) and plasma volume were unchanged. White blood cell (WBC) count was significantly increased at AM compared with in Europe on Days 4 and 10 of acclimatisation (P<0.01), but was not different by Day 16. In conclusion, horses exposed to hot humid environmental conditions without prior acclimatisation are able to accommodate these stresses and, with appropriate management, remain fit and clinically healthy, without significant risk of heat illness or heat‐related disorders, provided they are allowed sufficient time to recover from transport, acclimatisation is undertaken gradually and they are monitored appropriately.
A prospective study of the roles ofClostridium difficileand enterotoxigenicClostridium perfringensin equine diarrhoea
Authors: WEESE J. S. , STAEMPFLI H. R. , PRESCOTT J. F. 
Published: April 2007

SummaryFaecal samples from adult horses and from foals with diarrhoea or with normal faeces were evaluated for the presence ofClostridium difficile, C. difficiletoxins,C. perfringensenterotoxin (CPE) andC. perfringensspore counts.Clostridium difficilewas isolated from 7/55 horses (12.7%) and 11/31 foals (35.5%) with colitis, but from 1/255 normal adults (0.4%) and 0/47 normal foals (P<0.001).Clostridium difficiletoxinsAand/orBwere detected in 12/55 diarrhoeic adults (21.8%) and 5/30 diarrhoeic foals (16.7%) but in only 1/83 adults (1.2%) and 0/21 foals with normal faeces (P<0.001 and P<0.05, respectively).Clostridium perfringensenterotoxin was detected in 9/47 diarrhoeic adults (19%) and 8/28 diarrhoeic foals (28.6%), but was not detected in 47 adult horses (P<0.002) or 4 foals (P = 0.22) with normal faeces. The positive predictive value of isolation ofC. perfringenswith respect to the presence of CPE was only 60% in adult horses and 64% in foals. There was no association between totalC. perfringensspore count and CPE in the faeces. The overall mortality rate from colitis was 22% for adult horses and 18% for foals.Clostridium difficiletoxin‐positive adult horses with colitis were less likely to survive thanC. difficile‐negative horses with colitis (P = 0.03). This study provides further evidence thatC. difficileand enterotoxigenicC. perfringensare associated with equine enterocolitis.
A study of ten cases of focal peritarsal infection as a cause of severe lameness in the Thoroughbred racehorse: clinical signs, differential diagnosis, treatment and outcome
Authors: PILSWORTH R. C. , HEAD M. J. 
Published: April 2007

SummaryThe differential diagnoses of tarsal joint infection, fracture and peritarsal focal infection are of particular importance in practice. The objective of the present report is to provide additional clinical data to assist in the understanding of one of these conditions. The haematological parameters, clinical signs, treatment and outcome of 10 cases of severe lameness associated with peritarsal infection are reviewed. All horses had a significant rise in rectal temperature. The majority of cases (6/10) had haematological changes consistent with acute bacterial infection on the day of first examination. In the remaining cases these changes were not apparent on a blood sample taken on the first examination, but became so after 24 h. Nine out of 10 cases made a complete recovery on a regimen of i.v. antibiotic therapy, in conjunction with administration of nonsteroidal anti‐inflammatory drugs and repeated forced exercise. One case developed osteomyelitis of the third and fourth metatarsal bones, but made a full recovery in due course. It is concluded that, in the majority of cases, prompt treatment with antibiotic therapy, analgesics and forced exercise results in complete resolution of the condition.
A long‐term study of 277 cases of equine sinonasal disease. Part 1: Details of horses, historical, clinical and ancillary diagnostic findings
Authors: TREMAINE W. H. , DIXON P. M. 
Published: April 2007

SummaryThe clinical and ancillary diagnostic findings in equine sinnasal disease were studied. The diagnoses in 277 referred (1984–1996) cases of equine sinonasal disease included the following (% all cases): 67 cases (24.2%) primary sinusitis, 61 (22.0%) dental sinusitis, 37 (13.4%) sinus cysts, 22 (7.9%) sinonasal neoplasia, 21 (7.6%) progressive ethmoid haematoma, 17 (6.1%) sinonasal trauma, 13 (4.7%) sinonasal mycosis, 11 (4.0%) rostral maxillary cheek tooth infection, 7 (2.5%) sinonasal polyps, 7 (2.5%) cases of nasal epidermal inclusion cysts and 14 (5.1%) miscellaneous sinonasal disorders. Many disorders showed similar clinical signs including nasal discharge (present in 88% of all cases) and facial swelling (46%). Most disorders were chronic, with a median duration of signs of 12 weeks (range 3 days‐6 years) priorto referral. Sinus cysts and sinonasal neoplasia were significantly (P<0.05) more frequently associated with gross distortion of the nasal passages and facial bones than the other sinonasal disorders. Endoscopic changes were detectedper nasumin 91% of cases, but contributed to the exact diagnosis in only 20%. Radiography revealed abnormalities in 81% of cases but was diagnostically useful in only 36%. Sinoscopy was diagnostically useful in 70% of the 61 cases where used.
Temporary transvenous atrial pacing in horses: threshold determination
Authors: van LOON G. , LAEVENS H. , DEPREZ P. 
Published: April 2007

SummaryThe purpose of this study was to perform temporary atrial pacing and to determine the atrial strength‐duration (S‐D) curve which displays the minimal pulse intensity necessary to achieve atrial capture. In 7 horses, atrial pacing was applied using a temporary pacing catheter and a pacemaker as electrical pulse generator. Using the stimulus reduction method, 3 approaches for atrial threshold determination were used. With the fixed pulse width method, at several pulse widths, the corresponding minimal amplitudes to achieve capture were determined, describing an S‐D curve. With the fixed amplitude method, the corresponding threshold pulse widths were determined at several fixed amplitudes. The third method proved to be the best and was a combination of both aforementioned methods to determine 2 points of the S‐D curve. From these 2 points the whole S‐D curve was calculated using a mathematical equation. Temporary pacing can be used to terminate atrial flutter, to induce atrial arrhythmias or to obtain more information about the electrophysiological properties of the heart, such as the atrial refractory period, atrial vulnerability and atrioventricular conduction.
Equine thoracoscopy: normal anatomy and surgical technique
Authors: PERONI J. F. , HORNER N. T. , ROBINSON N. E. , STICK J. A. 
Published: April 2007

SummarySix normal, healthy horses age 3–10 years underwent left and right thoracoscopic examination using a rigid telescope. A minimum of 30 days was allowed between procedures. Horses were restrained in stocks and sedated with a continuous detomidine infusion. After surgical preparation of the hemithorax elected for surgery, and administration of local or regional anaesthesia of the surgery sites, thoracoscopy was completed during two 15 min pneumothorax periods. During the procedures, the thoracic structures were viewed using a 57 cm, 10 mm diameter, 30° rigid telescope connected to a digital camcorder to allow computer capture of digital images. The telescope was inserted into the thoracic cavity via 3 different intercostal spaces. The 8th, 10th and 12th intercostal spaces were randomly selected and used among horses. The exploration of each hemithorax started from the dorsal‐caudal quadrant continued toward the cranial thorax and was completed by observing the diaphragmatic and caudal pulmonary region.Collapsed lung, aorta, oesophagus and diaphragm were viewed readily in either hemithorax. On exploration of the right hemithorax, the azygos vein, thoracic duct and pulmonary veins were also identified. Horses tolerated thoracoscopy well. Signs of discomfort, such as increased respiratory rate, coughing and decreased level of sedation, were associated with lung collapse in one horse, with pneumothorax on 2 occasions, and when the thorax was approached through the 8th intercostal space. Surgery performed via the 8th intercostal space was hindered by the rigidity of the 8th and 9th ribs, and by the presence of a greater musculature, which did not allow easy cranial and caudal movements of the telescope.
Equine dysautonomia (grass sickness) is associated with altered plasma amino acid levels and depletion of plasma sulphur amino acids
Authors: MCGORUM B. C. , KIRK J. 
Published: April 2007

SummaryTo determine whether equine dysautonomia (ED) is associated with alterations in plasma amino acid metabolism, plasma amino acid profiles were determined for horses with acute (n = 10), subacute (n = 6) and chronic (n = 7) ED and for healthy cograzing horses (n = 6) and control horses (n = 10). Horses with acute ED had perturbations in plasma amino acid profiles resembling those of severe protein malnutrition. In addition, horses with ED and cograzing healthy horses had depletion of the plasma sulphur amino acids cyst(e)ine and methionine. As similar plasma amino acid perturbations occur in subacute/chronic cyanide toxicity, the role of cyanogenic glycosides in the aetiology of ED warrants further study. Unfortunately, amino acid analysis cannot be used as a definitivepremortemdiagnostic test for ED, since there was overlap in the individual amino acid levels of control, cograzing and ED horses.
Signal decomposition method of evaluating head movement to measure induced forelimb lameness in horses trotting on a treadmill
Authors: KEEGAN K. G. , PAI P. F. , WILSON D. A. , SMITH B. K. 
Published: April 2007

SummaryIn horses at a trot, the head moves up and down twice in one stride. In horses with unilateral forelimb lameness this movement is asymmetric. Computer‐assisted kinematic analysis of vertical head movement can be used to quantify objectively lameness in horses in clinical trials. However, in mild lameness, absolute measurements of vertical head height may not be sensitive enough to detect small differences in lameness, and extraneous head movement by the horse due to curiosity, excitement or nervousness interferes with the accurate measurement of vertical head movement asymmetry. We describe a simple, signal‐decompensation method of evaluating vertical head movement using a model of induced mild foot lameness in 9 horses. The technique assumes that the vertical head movement pattern can be broken down into 3 components; the vertical head movement caused by forelimb lameness (A1), the amplitude of the natural biphasic vertical head movement (A2) and extraneous head movement. Extraneous head movement is mathematically removed from the vertical head movement pat tern.A1andA2are then calculated. After induction of lameness, meanA1increased by 1.63 cm (range 0.10–3.33 cm, P = 0.005). MeanA2did not significantly change after lameness induction. Error in reproduction of the original head movement pattern was 0.3–0.5%. We calculated that a hypothetical clinical trial would require 12 subjects for testing to be 80% certain that this difference would be successfully detected using this method of lameness evaluation.