bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of a cold‐adapted, intranasal, equine influenza vaccine: challenge trials
Authors: TOWNSEND H. G. G. , PENNER S. J. , WATTS T. C. , COOK A. , BOGDAN J. , HAINES D. M. , GRIFFIN S. , CHAMBERS T. , HOLLAND R. E. , WHITAKER‐DOWLING P. , YOUNGNER J. S. , SEBRING R. W. 
Published: April 2007

SummaryA randomised, controlled, double‐blind, influenza virus, aerosol challenge of horses was undertaken to determine the efficacy of a cold‐adapted, temperature sensitive, modified‐live virus, intranasal, equine influenza vaccine. Ninety 11‐month‐old influenza‐naïve foals were assigned randomly to 3 groups (20 vaccinates and 10 controls per group) and challenged 5 weeks, 6 and 12 months after a single vaccination. Challenges were performed on Day 0 in a plastic‐lined chamber. Between Days 1 and 10, animals were examined daily for evidence of clinical signs of influenza. Nasal swabs for virus isolation were obtained on Day 1 and Days 1 to 8 and blood samples for serology were collected on Days 1, 7 and 14. There was no adverse response to vaccination in any animal. Following challenge at 5 weeks and 6 months, vaccinates had significantly lower clinical scores (P = 0.0001 and 0.005, respectively), experienced smaller increases in rectal temperature (P = 0.0008 and 0.0007, respectively) and shed less virus (P<0.0001 and P = 0.03, respectively) over fewer days (P<0.0001 and P = 0.002, respectively) than did the controls. After the 12 month challenge, rectal temperatures (P = 0.006) as well as the duration (P = 0.03) and concentration of virus shed (P = 0.04) were significantly reduced among vaccinated animals. The results of this study showed that 6 months after a single dose of vaccine the duration and severity of clinical signs were markedly reduced amongst vaccinated animals exposed to a severe live‐virus challenge. Appropriate use of this vaccine should lead to a marked reduction in the frequency, severity and duration of outbreaks of equine influenza in North America.
Opsonic capacity of foal serum for the two neonatal pathogensEscherichia coliandActinobacillus equuli
Authors: GRÖNDAHL G. , STERNBERG S. , JENSEN‐WAERN M. , JOHANNISSON A. 
Published: April 2007

SummaryTwo of the most commonly isolated foal pathogens areEscherichia coliandActinobacillus equuli.The hypothesis tested in this study was that young foals carry a lower opsonic capacity for these bacteria compared to adult horses. A flow‐cytometric method for the phagocytosis of these by equine neutrophils was established. The opsonic capacity of serum from healthy foals from birth to age 6 weeks was evaluated and related to the concentrations of IgGa and IgGb. Phagocytosis of yeast was used as a control. Serum was required for phagocytosis, with higher concentrations forE. colithan forA. equuli.Ingestion of colostrum led to a significantly higher serum opsonic capacity. After that, there was no consistent age‐related trend for opsonic capacity for the different microbes. Foal serum showed similar or higher opsonisation ofE. coliandA. equulicompared to serum from mature individuals. During the studied period, the predominance among IgG subisotypes switched from IgGb to IgGa. Although the overall correlation between concentrations of IgG subisotypes and serum opsonic capacity was poor, sera with IgGb levels below 1.9 mg/ml induced lower opsonisation ofE. coliand yeast, but not ofA. equuli.Complement activation was important for opsonisation of all tested microbes. The results of this study are significant to the understanding of a key immunological facet in the pathophysiology of equine neonatal septicaemia in clinical practice.
Concentration of collagen, aggrecan and cartilage oligomeric matrix protein (COMP) in synovial fluid from equine middle carpal joints
Authors: SKIÖLDEBRAND E. , LORENZO P. , ZUNINO L. , RUCKLIDGE G. J. , SANDGREN B. , CARLSTEN J. , EKMAN S. 
Published: April 2007

SummaryThe aim of the present investigation was to study the metabolic activity of the third carpal bone and the release of COMP, aggrecan and collagentype IImolecules in the synovial fluid as a result of injury. Cartilage oligomeric matrix protein (COMP), aggrecan and collagentype IIor fragments of these molecules released to the synovial fluid and serum (COMP) were quantified in samples from 73 left equine middle carpal joints from 2 breeds with different activity profiles (52 Standardbred trotters [STB] and 21 Swedish Warmblood riding horses [SWH]) and different articular cartilage lesions. Synovial and serum samples were analysed using inhibition ELISA for COMP and aggrecan. An ELISA that combines features of both the competitive and capture ELISAs was used for collagentype II.COMP and aggrecan concentrations decreased in synovial fluid from the joints with moderate lesions of STB compared with the normal joints; COMP from 16.6 to 12.0 μg/ml and aggrecan from 93.0 to 68.1 μg/ml. In serum, COMP concentrations were also lowered in the STB with moderate lesions compared with the normal joints, while in the SWH, the COMP concentration in synovial fluids from joints with moderate lesions was somewhat increased at 19.6 μg/ml compared with the normal joints (17.6 μg/ml). The ratio between aggrecan/COMP in the synovial fluid from joints with moderate lesions was higher in the STB (6.2) than in the SWH (3.4). The level of collagentype IIin synovial fluid was higher in the SWH (8.8 μg/ml) than the STB (1.6 μg/ml), but there was no correlation between joint damage and collagen concentrations in synovial fluids (10.0 and 1.8 μg/ml in joints with moderate lesions from SWH and STB, respectively). A marked difference in COMP synthesised upon metabolic labelling between the normal and osteoarthritic cartilage was seen and the synthesis of COMP in the articular cartilage of the third carpal bone with moderate articular lesions (from an STB) was lower than in the joint with mild lesions.This difference between breeds may reflect different load characters, in release of macromolecules in osteoarthritic and normal joints. This a novel finding that should be considered in studies of equine traumatic arthritis.
Proximal interphalangeal arthrodesis in 22 horses
Authors: SCHAER T. P. , BRAMLAGE L. R. , EMBERTSON R. M. , HANCE S. 
Published: April 2007

SummaryThe purpose of this study was to evaluate a new method of internal fixation technique for pastern arthrodesis. Pastern arthrodeses are performed commonly in horses with chronic osteoarthritis of the pastern joint or, in cases of acute traumatic injury to the pastern, in which the weightbearing bony column must be restored. Chronic osteoarthritis of the pastern is a frequent cause of lameness in the equine athlete and is evidenced by chronic lameness localised to the pastern joint, and supported radiographically by periosteal proliferation and loss of joint space. Nonsurgical and surgical treatments have both been described in the literature. Complications following pastern arthrodesis have been reported on several occasions and appear to focus on excessive periarticularexostoses and increased time in a cast due to prolonged time to bony fusion.The hospital records of horses presenting for pastern arthrodesis to the Rood and Riddle Equine Hospital in Lexington, Kentucky, were reviewed and 22 met criteria for inclusion in the study. Horses with chronic osteoarthritis of the proximal interphalangeal joint or horses with an acute traumatic injury to the pastern undergoing pastern arthrodesis with one of the following techniques were included in the study. Horses with severe comminution of the middle phalanx were excluded. Three 5.5 mm cortical bone screws placed in lag fashion alone or in combination with a 4 or 3 hole dynamic compression plate affixed with 4.5 mm cortical bone screws were compared. A lower limb fibreglass cast was applied in all cases. Period in cast, time to return to intended use, complications encountered and outcome were evaluated.Seven of the 8 hindlimbs treated with the combination technique became sound. Three out of 6 of the front limbs treated with the combination technique became sound. Four of the 5 horses with hindlimbs, and one of the 2 with front limbs, treated with screws only returned to their intended use.The type of internal fixation did not appear to influence the overall number of horses returning to the intended level of performance. The period spent in cast and the time to return to soundness were decreased in horses operated on using the combination technique. We concluded that, in the immediate postoperative period, the combination of the parallel screw technique with a dorsally‐applied dynamic compression plate provides the most stable and secure fixation, minimising motion, expediting bone remodelling and therefore favouring rapid fusion of that joint.
Postprandial arterial vasodilation in the equine distal thoracic limb
Authors: HOFFMANN K. L. , WOOD A. K. W. , GRIFFITHS K. A. , EVANS D. L. , GILL R. W. , KIRBY A. C. 
Published: April 2007

SummaryThe effects of feeding on blood flow to the equine foot are poorly understood. In a temperature‐controlled room, duplex Doppler ultrasonographic observations were made pre‐ and postprandially of the lateral proper palmar digital artery of 5 horses, randomly assigned to twice and 4 times daily feeding in an unbalanced 2 period crossover design. Arterial diameter and blood velocity were measured over 4 h and additional observations made of heart rate, blood pressure, total plasma protein, packed cell volume, plasma glucose and insulin. There was no effect of the feeding regimen on any variable. Postprandially, there were significant increases in arterial diameter, blood velocity, total plasma protein, plasma glucose and insulin; the other variables were unchanged. It appeared that the normal postprandial response was an increase in blood flow to the foot. The value of ultrasonography for noninvasive investigation of the peripheral vasculature of the conscious horse was established; and in the future it may have a role in the diagnosis of vascular diseases of the foot.
Effects of training on resting peripheral blood and BAL‐derived leucocyte function in horses
Authors: RAIDAL S. L. , ROSE R. J. , LOVE D. N. 
Published: April 2007

SummaryIn this study, the effects of prolonged, high intensity training on aspects of peripheral blood and bronchoalveolar lavage (BAL)‐derived leucocyte function were evaluated in 8 horses. All horses undertook a 7 week endurance training programme, followed by 5 weeks of high intensity training (HIT). Thereafter, horses were divided into control (C) and overtraining (OT) groups. The frequency and intensity of training were increased more substantially for horses in the OT group. Training was terminated in week 32 when horses in the OT group demonstrated a significant performance reduction. Peripheral blood and BAL samples were collected from 4 horses in C and OT groups in training weeks 7, 11, 14, 18, 22, 28 and 32. Flow cytometric techniques were used to assess phagocytosis by peripheral blood neutrophils and pulmonary alveolar macrophages (PAM), and oxidative burst activity of neutrophils, PAM, peripheral blood and BAL‐derived lymphocytes. Peripheral blood neutrophil phagocytosis (internalisation) increased during the initial HIT period and decreased from week 16 when the training workload was increased forboth groups. The oxidative burst activity of peripheral blood neutrophils and lymphocytes similarly increased and then decreased in response to training. The oxidative burst activity of PAM was reduced towards the end of the overtraining phase of the programme. Pulmonary alveolar macrophage phagocytosis and oxidative burst activity of BAL‐derived lymphocytes demonstrated no change throughout the course of the study. There was no difference in results obtained from C or OT group horses, suggesting that protracted HIT, rather than overtraining, was associated with impaired cell function.The detrimental effects observed in peripheral blood neitrophil and PAM function may indicate impaired nonspecific immunity which may adversely affect the health and performance of horses undergoing protracted periods of intense training.
Specificity and reversibility of the training effects on the concentration of Na+, K+‐ATPase in foal skeletal muscle
Authors: SUWANNACHOT P. , VERKLEIJ C. B. , KOCSIS S. , VAN WEEREN P. R. , EVERTS M. E. 
Published: April 2007

SummaryThe purpose of the present study was to determine whether training and detraining affect the Na+, K+‐ATPase concentration in horse skeletal muscles, and whether these effects are specific for the muscles involved in the training programme. Twenty‐four Dutch Warmblood foals age 7 days were assigned randomly to 3 groups: Box (box‐rest without training), Training (box‐rest with training: short‐sprint) and Pasture (pasture without training). Exercise regimens were carried out for 5 months and were followed by 6 months of detraining. Five of the foals in each group were subjected to euthanasia at age 5 months and the remaining foals at 11 months. Muscle samples were collected from the deep part of thegluteus medius, semitendinosusand masseter muscles. The Na+, K+‐ATPase concentration was quantified by [3H]ouabain binding.In the Training group, the concentration of Na+, K+‐ATPase ingluteus mediusandsemitendinosusmuscle, but not in masseter muscle, showed a relative increase of 20% (P<0.05) as compared to Box foals. After detraining for the subsequent 6 months, the concentration of Na+, K+‐ATPase insemitendinosusmuscle remained the same, while that ingluteus mediusmuscle was reduced by 10%.It is concluded that: 1) short‐sprint training for 5 months induced an increase of the Na+, K+‐ATPase concentration ingluteus mediusandsemitendinosusmuscles of the foal. Interestingly, this effect persisted during the 6 months of the detraining period. Whether the higher Na+, K+‐ATPase concentration due to training of young foals leads to a better athletic performance when they become mature still needs to be established; 2) the factors that initiate an increase in Na+, K+‐ATPase concentration following training are likely to be located in the muscle itself and 3) the training effect may last for several months after returning to normal activity, especially in muscles containing a high percentage of fast‐twitch fibres.
Effects of inhalation of albuterol sulphate, ipratroprium bromide and frusemide on breathing mechanics and gas exchange in healthy exercising horses
Authors: BAYLY W. M. , SLOCOMBE R. F. , SCHOTT H. C. , HINES M. T. , SIDES R. H. , HAKALA J. E. 
Published: April 2007

SummaryThe possibility that pre‐exercise inhalation of a bronchodilator by healthy horses could improve their mechanics of breathing and enhance performance was investigated. Ipratropium bromide (0.35 μg/kg bwt; n = 7) was administered by nebulisation 30 min before exercise and frusemide (1 mg/kg bwt; n = 6) was given in the same manner 2 h before exercise. Albuterol sulphate (360 and 720 μg; n = 7) were administered with a metered dose inhaler 2 h before exercise. Each drug was investigated independently of the others using cross‐over protocols. Horses completed incremental exercise tests and oxygen consumption, carbon dioxide production, arterial blood gases, heart rate and measures of breathing mechanics including total pulmonary resistance (RL) and nasopharyngeal resistance (RU) were determined for each exercise intensity. The resistance of the lower airways was calculated subsequently from the difference between RLand RU. None of the drugs tested had an effect on any of the variables measured, possibly because maximal bronchodilation is stimulated in healthy horses by the normal sympathoadrenergic response to exercise. Therefore, the pre‐exercise inhalation of a bronchodilator by a healthy horse is unlikely to improve performance capacity.
A case‐control study of respiratory disease in Thoroughbred racehorses in Sydney, Australia
Authors: CHRISTLEY R. M. , HODGSON D. R. , ROSE R. J. , WOOD J. L. N. , REID S. W. J. , WHITEAR K. G. , HODGSON J. L. 
Published: April 2007

SummaryIn order to investigate the role of infectious agents in the aetiology of lower respiratory tract disease in Thoroughbred racehorses, a matched case‐control study was conducted. Cases were identified by the presence of coughing, and were compared to a control population matched on time of sample collection and location within the same training establishment. Tracheal wash samples were collected from 100 cases and 148 controls. Case horses were more likely than controls to have endoscopic and cytological evidence of airway inflammation. There was no significant association between serological evidence of infection by commonly implicated respiratory viruses and coughing. Similarly, mycoplasma were rarely isolated and were not associated with disease. In contrast, there was a strong association between isolation of greater than a total of 103colony‐forming units/ml of tracheal wash and coughing. Individual bacterial species associated with disease includedStreptococcus zooepidemicus, Streptococcus pneumoniae, Streptococcus suis, Streptococcus sanguis, Pasteurellaspp andBordetella bronchiseptica.This study provides evidence of the role of bacterial infection in the aetiology of lower respiratory tract inflammation in racehorses. However, in 58% of cases, few or no bacteria were isolated. Hence, at the time of identification of disease, there was no evidence of viral, bacterial or mycoplasmal infection in the majority of coughing horses. The aetiology of the signs observed in these horses requires further investigation.
Laryngeal paralysis: a study of 375 cases in a mixed‐breed population of horses
Authors: DIXON P. M. , MCGORUM B. C. , RAILTON D. I. , HAWE C. , TREMAINE W. H. , PICKLES K. , MCCANN J. 
Published: April 2007

SummaryReferred cases (n = 375) of laryngeal paralysis (1985–1998) from a mixed‐breed equine population included 351 (94%) cases of recurrent laryngeal neuropathy (RLN) (idiopathic laryngeal hemiplegia) and 24 cases (6%) of laryngeal paralysis from causes other than RLN. Laryngeal movements were classified endoscopically into one of 6 grades, in contrast to the usual 4 grades. The RLN cases had a mediangrade 4laryngeal paralysis, of which 96% were left‐sided, 2% right‐sided and 2% bilaterally affected. RLN cases included 204 (58%) Thoroughbred, 96 (27%) Thoroughbred‐cross, 23 (7%) draught, 16 (5%) Warmbloods and 10 (3%) other breeds, including only 4 (1%) ponies. The median age of RLN cases at referral was 6 years (range 2–12) and their median height was 170.2 cm. The work of RLN horses included National Hunt racing (42%), flat racing (1%), hunting (19%), eventing (16%) and miscellaneous work (22%). Reported presenting signs in RLN‐affected horses included abnormal exercise‐related respiratory sounds in 90% and reduced exercise tolerance in only 64%. However, many horses were referred before their exercise tolerance could be fully assessed. Forty percent of the RLN cases had intercurrent disorders, including 10% with additional upper respiratory and 7% with lower respiratory tract diseases. The 24 nonidiopathic RLN cases included 12 with bilateral laryngeal paralysis, 11 (92%) of which were ponies. Bilateral laryngeal paralysis occurred with hepatic encephalopathy in 7 cases and following general anaesthesia in 2 cases. The 12 cases of acquired unilateral laryngeal paralysis included 7 caused by guttural pouch mycosis.
Racehorse injuries, clinical problems and fatalities recorded on British racecourses from flat racing and National Hunt racing during 1996, 1997 and 1998
Authors: WILLIAMS R. B. , HARKINS L. S. , HAMMOND C. J. , WOOD J. L. N. 
Published: April 2007

SummaryFor improvements to the safety and welfare of racehorses to be possible, it is essential to have access to basic descriptive information about the veterinary incidents encountered during horseracing. A 3 year surveillance study (1996–1998) was conducted by The Jockey Club into racing injuries, other postrace clinical problems and fatalities from all 59 British racecourses (mainland Britain only) to identify risk factors. During the survey there were 222,993 racing starts: 106,897 starts in flat races on turf (47.9%), 26,519 starts in flat races on all‐weather surfaces (11.9%), 30,932 starts in chases on turf (13.9%), 51,786 starts in hurdle races on turf (23.2%) and 6,859 starts in National Hunt flat races (3.1%). Information was recorded about age of horses, racing surfaces and clinical events observed or attended by a veterinary team of 2 clinicians and one veterinary surgeon employed by the racing authority. Of the 2358 clinical events re ported (1.05% of all starts), 1937 involved the musculoskeletal system and 421 involved other body systems. Six hundred and fifty‐seven incidents (0.29% of starts) resulted in death or euthanasia. Eighty‐one percent of limb injury reports involved forelimbs and 46% involved flexor tendons/suspensory ligaments. Nonlimb problems included epistaxis (0.83/1000 starts), ‘exhausted horse syndrome’ (0.47/1000 starts) and paroxysmal atrial fibrillation (0.20/1000 starts). Incidents including fatalities per 1000 starts were 24.7 from chases, 19.45 from hurdle races, 8.46 from National Hunt flat races and 3.97 from flat races. The overall tendon injury was higher in chases than in hurdle races, even though age‐specific rates of tendon injury were higher in hurdle races than in chases. The risk of injuries per start increased significantly with age, while softer racing surfaces were associated with fewer fatalities and injuries than firmer surfaces. The survey described in this paperhas provided an up‐to‐date description of the fatal and non‐fatal horseracing incidents under conditions on mainland Britain, enabling progress to be made towards improving the safety and welfare of racehorses.
The distribution of intratubular dentine in equine incisors: a scanning electron microscopic study
Authors: MUYLLE S. , SIMOENS P. , LAUWERS H. 
Published: April 2007

SummaryThe distribution of intratubular (peritubular) dentine was studied by scanning electron microscopy in 12 equine incisor teeth. High levels of intratubular dentine were found in the peripheral regions of the dentine. In these areas, a marked asymmetry occurred, as intratubular dentine was predominantly deposited onto the side of the dentinal tubular walls nearest to the dentino‐enamel junction. The quantity and asymmetry of intratubular dentine were reduced towards the centre of the tooth.The significance of these variations in the amount and distribution of intratubular dentine between the different dentinal regions is discussed.