bluuebunny/crossref_metadata_2025 huggingface dataset:
Measures of Redox Balance in Horses Undergoing Corrective Surgery Involving Strangulating Lesions of the Small Intestine
Authors: Bardell D.A. , Archer D.C. , Milner P.I.
Published: September 2015

Reasons for performing study

Colic remains a life‐threatening condition in the horse. Ischaemia and reperfusion following correction of small intestinal strangulation may produce oxidative stress. The ability to withstand oxidative stress depends on antioxidant levels and may be linked to horse survival.

Objectives

To measure peripheral antioxidant levels in horses undergoing exploratory laparotomy with small intestinal strangulation.

Study design

Case–control study.

Methods

Blood and plasma were collected from horses undergoing exploratory laparotomy for small intestinal strangulation and stored at −80°C. Controls involved non‐colic horses. Total plasma glutathione was measured spectrophotometrically at 412 nm using the 5,5′‐dithiobis‐(2‐nitrobenzoic acid) (DTNB, Ellman's reagent) reaction. Samples containing scavenger (to remove reduced glutathione, GSH) were used to measure oxidised glutathione (GSSG). Glutathione reductase (GR) activity (u/l) was measured as the rate of GSH production at 412 nm. Glutathione peroxidise (GPx) activity (u/l) was measured as the change in optical density (340 nm) following the consumption of NADPH after GSSG production. All assays were purchased from BioAssay Systems (Hayward, California). Clinical data including arterial blood gas analysis were collected on admission.

Results

Glutathione reductase activity in horses with strangulating small intestinal lesions was significantly reduced compared to control horses (12.2 ± 1.1 u/l vs. 15.9 ± 0.8 u/l, P = 0.03, n = 6) whereas GPx activity did not significantly differ between colic and control horses (155.7 ± 48.7 u/l vs. 167.3 ± 30.1 u/l, P = 0.84, n = 6). Total glutathione, reduced or oxidised glutathione did not differ significantly between control and colic horses. A positive correlation existed between GR activity and Ca2+ (r = 0.93) and K+ (r = 0.75) whereas a strong negative correlation was present between GR activity and HCO3− (r = −0.92) and PaCO2 (r = −0.96).

Conclusions

Reduced plasma glutathione reductase activity with small intestinal strangulation indicates oxidative stress and may be related to systemic electrolyte/bicarbonate abnormalities.

Ethical animal research: Study approval No. VREC219a. Explicit owner informed consent for inclusion of animals in this study was not stated. Source of funding: Supported by the School of Veterinary Sciences, University of Liverpool. Competing interests: None declared.
Is There Evidence for Functional 5‐Hydroxytryptamine 4 (5‐HT4) Receptors in the Equine Jejunum? An In Vitro Study to Explore Options for Use of Human Prokinetic Drugs, Acting as 5‐HT4 Receptors, in Horses
Authors: Delesalle C.J.G. , Callens C. , Van Colen I. , Lefebvre R.A.
Published: September 2015

Reasons for performing study

Selective 5‐HT4 receptor agonists such as prucalopride are used as human prokinetics, since activation of 5‐HT4 receptors on intestinal cholinergic neurons facilitates acetylcholine release. 5‐HT4 receptors, linked to adenylyl cyclase, act via generation of cAMP. None of the 4 in vitro studies on 5‐HT in horses provided evidence for neuronal 5‐HT4 receptors, but none used the protocol as described in human studies [1–4].

Objectives

To investigate whether functional 5‐HT4 receptors are present in the equine small intestine.

Study design and methods

In vitro organ bath set up, applying electrical field stimulation (EFS) in longitudinal and circular smooth muscle strips.

Results

Results were similar in both muscle layers. In the presence of 0.3 mmol/l NG‐Nitro‐L‐arginine methyl ester and 0.3 μmol/l apamine, excluding effects of the inhibitory transmitters NO and ATP, EFS induced voltage‐dependent on‐contractions; these were neurogenic as they were abolished by 3 μmol/l tetrodotoxin. At a voltage inducing 50% of the maximal amplitude, the submaximal EFS‐induced contractions were cholinergic as atropine (1 μmol/l) abolished them. Prucalopride (0.3 μmol/l) did not increase the amplitude of these submaximal EFS‐induced contractions. Even in the presence of the nonselective phosphodiesterase inhibitor IBMX, previously shown to enhance the effect of neuronal 5‐HT4 receptors by inhibiting breakdown of their 2nd messenger cAMP [5], prucalopride (3 μmol/l) had no influence. Also 5‐HT (10 μmol/l), a full agonist at 5‐HT4 receptors, tested in the presence of methysergide and granisetron to exclude interaction with other 5‐HT receptor subtypes, did not enhance EFS‐induced submaximal contractions.

Conclusions

There is no evidence for presence of 5‐HT4 receptors on the cholinergic neurons of the equine small intestine. These results question the application of 5‐HT4 prokinetic drugs in horses.

Ethical animal research: Research ethics committee oversight not currently required by this conference: the study was performed on material collected at an abattoir. Sources of funding: None. Competing interests: None declared.
Ethmoidal Infection with Aspergillus spp. in 3 Horses: Successful Treatment by Transendoscopic Removal of Mycotic Plaques Alone or in Combination with Systemic Itraconazole
Authors: Theelen M.J.P. , Siegers E.W. , Ensink J.M.
Published: September 2015

Reasons for performing study

Ethmoidal infection with Aspergillus spp. is rarely reported in horses. Three horses suffering from unilateral infection with Aspergillus spp. of the ethmoid with varying underlying conditions are described.

Study design

Case series.

Methods

Diagnosis was made by endoscopy of the ethmoid (presence of white mycotic plaques on a layer of thick yellow mucus) and confirmed by fungal culture (A. fumigatus) and/or cytology. Clinical details and outcome were obtained from the medical records and by contacting owners.

Results

Horse 1 and 2 had a progressive ethmoid haematoma (PEH) and had been treated for over 5 months with repeated formalin injections (one horse after initial surgical debulking of the PEH that also invaded the maxillary and sphenopalatine sinuses) before the infection with Aspergillus was diagnosed. The third horse, presented with poor performance and nasal discharge, had congenitally abnormal anatomy of the right dorsal nasal passage and right ethmoids. In the 2 horses with PEH the mycotic plaques were removed transendoscopically successfully. After 6 weeks the infection was no longer present at endoscopy in both horses (follow‐up endoscopy: Horse 1 no relapse >16 months and Horse 2 no relapse >7 months). In the third horse, it was not possible to remove all mycotic plaques, therefore systemic treatment with itraconazole (3 mg/kg bwt q. 12 h for 8 weeks orally) was started. After 8 weeks, the clinical signs had resolved and endoscopy showed that the Aspergillus infection had cleared (follow‐up: no relapse >14 months). No side effects were seen with systemic itraconazole treatment.

Conclusions

In horses with underlying ethmoidal conditions, secondary infection with Aspergillus spp. may occur. Transendoscopic removal of the mycotic plaques alone may be successful and if this approach is not feasible or unsuccessful, systemic treatment with itraconazole can be considered.

Ethical animal research: Research ethics committee oversight not currently required by this conference: retrospective study of clinical records. Owners gave informed consent for their horses' inclusion in the study. Source of funding: Utrecht University. Competing interests: None declared.
Equine Cyathostominae Can Develop to Infective Third Stage Larvae on Straw Bedding
Authors: McGirr E.C. , Denwood M.J. , McGoldrick J. , Love S.
Published: September 2015

Reasons for performing study

To determine whether horses could become infected with cyathostomins when bedded in deep litter straw.

Objectives

The specific objective of the study was to determine whether cyathostomin eggs could hatch and develop to infective larval stages on straw bedding.

Study design

Experimental study.

Methods

Four horticultural incubators were set up to simulate 3 straw bedding scenarios, and one grass turf control. Faeces were placed on 12 plots, and larval recoveries performed on samples of straw/grass over a 17‐day period. The plots within incubators A, B, and C contained dry straw, watered straw, and deep litter straw, respectively. Plot 1 of each incubator contained a faecal pat of a horse that tested negative for strongyle eggs – these were to serve as negative control plots. Plots 2 and 3 of each incubator contained a faecal pat from horses that had average faecal worm egg counts (FWEC) of 269 epg and 921 epg, respectively. A thermostat within each incubator was set to maintain an environmental temperature of approximately 20°C.

Results

No L3 larvae were recovered from the control plots of each incubator, and none were recovered from any of the plots within Incubator A. L3 larvae were first detected on plots 2 and 3 of Incubator B on Day 8, and on plot 3 of incubators C and D on Day 10.

Conclusions

It is evident that equine Cyathostominae can develop to infective L3 larvae on straw bedding, but only when the straw is moist. Therefore, it may be speculated that a horse bedded in deep litter straw may become infected by ingesting the infective L3 larvae contaminating the straw.

Ethical animal research: Not applicable. Source of funding: E.C. McGirr was supported by a World Horse Welfare Undergraduate Bursary 2014. Competing interests: None declared.
Head and Pelvic Movement Asymmetries at Trot in Riding Horses Perceived as Sound by Their Owner
Authors: Rhodin M. , Egenvall A. , Andersen P.H. , Pfau T.
Published: September 2015

Reasons for performing study

Recent studies evaluating owner sound horses have identified a large proportion of horses with motion asymmetries but the prevalence, type and magnitude of asymmetries have not been investigated. The increasing use of objective lameness evaluation necessitates a further characterisation of the differences between lameness and motion asymmetries.

Objectives

To investigate prevalence, and quantify type and magnitude of motion asymmetries during straight‐line trot in riding horses, perceived sound by their owners.

Study design

Cross‐sectional prospective study.

Methods

Vertical head and pelvic movement symmetry was measured in 220 Warmblood riding horses, all functioning in daily work and considered sound by their owners; 100 of these individuals had been included in a previous report [1]. Body‐mounted uni‐axial accelerometers were used and differences between maximum and minimum head (HDmax, HDmin) and pelvic (PDmax, PDmin) vertical displacement between left and right forelimb and hindlimb stances were calculated during straight‐line trot. Previously used symmetry thresholds (absolute differences >6 mm for the head and >3 mm for the pelvic variables) were used.

Results

The thresholds for symmetry were exceeded for 159 horses (72%) for at least one variable, HDmax (n = 41, mean 12.7 mm, s.d. 5.5), HDmin (n = 58, mean 14.3 mm, s.d. 7.1), PDmax (n = 87, mean 6.5 mm, s.d. 3.10), PDmin (n = 77, mean 5.7 mm, s.d. 2.1). Contralateral and ipsilateral concurrent fore‐ and hindlimb asymmetries were detected in 41 and 49 horses, respectively.

Conclusions

A surprisingly large proportion (72%) of horses perceived as sound by their owner showed movement asymmetries during straight‐line trot. It is not known to what extent these asymmetries are related to pain or mechanical abnormalities as opposed to ‘normal variation’ and this leads to 2 potential welfare problems – either too many horses in training are actually ‘lame’ or many horses categorised as ‘lame’ have no locomotor system disease.

Ethical animal research: This study was conducted within guidelines of the participating sites institutional animal care and use procedures (C 206/10, C48/13) and informed consent for data collection was obtained from the horse owners prior to the study. Source of funding: None. Competing interests: None declared.
Goniometric Measurement of Limb Stiffness: Validation of a Potential Predictor of Tendon Healing
Authors: Tucker R. , Jacklin B.D. , Gillespie S. , Vaughan L. , Fiske‐Jackson A.R. , Smith R.K.
Published: September 2015

Reasons for performing study

Injury to the superficial digital flexor tendon (SDFT) is common in equids, with a high risk of re‐injury associated with changes in tendon stiffness. In vivo measurement of limb stiffness has been shown to correlate with tendon stiffness after injury [1] but requires kinematic analysis which is impractical in a clinical setting. We have developed a simple system for measuring limb stiffness statically, which could be used as a tool for monitoring SDFT healing.

Objectives

To validate a goniometric measurement of limb stiffness.

Study design

Cross sectional study.

Methods

Initially, forelimb stiffness indices were determined at the walk for 6 equids using a validated kinematic analysis [1]. Limb stiffness indices were then calculated using portable floor scales to record ground reaction force (GRF), and an electrogoniometer to record metacarpophalangeal joint angle. Goniometric limb stiffness indices were subsequently measured in 11 horses ranging from 2 to 20 years of age, with no clinical evidence of SDFT injury. Strength and significance of correlation and agreement between the measurement methods was assessed and association between limb stiffness, limb (left vs. right), weight and age of horse and were calculated.

Results

There were strong positive correlations between GRF and joint angle (R2 = 0.98) and between the static and kinematic methods (R = 0.78, P<0.01). There was a positive correlation between limb stiffness and weight (R2 = 0.85, P<0.01), but no association with age or limb.

Conclusions

This study validated the measurement of limb stiffness in a clinical setting. The positive correlation of limb stiffness and weight supports the theory of an optimised limb spring [2] for energy‐efficient cursorial locomotion which may, in turn, provide a clinically‐relevant measure of running efficiency and therefore the quality of tendon healing post injury.

Ethical animal research: Owner consent was obtained. Source of funding: None. Competing interests: None declared.
What Effect Does Medium and Extended Trot Have on the Kinematics of the Forelimb in Dressage Horses?
Authors: Walker V.A. , Tranquille C.A. , Dyson S.J. , Newton R. , Murray R.C.
Published: September 2015

Reasons for performing study

Metacarpophalangeal joint hyperextension overload is increasingly being recognised in dressage horses and, like forelimb suspensory ligament injury, tends to be seen in horses with extravagant trot steps. However, there is limited understanding of the effects of different paces within the trot on forelimb movement, therefore it is difficult to advise rationally on prevention or management of these types of injury.

Objectives

To compare forelimb kinematics of collected and medium or extended trot in dressage horses.

Study design

Prospective study.

Methods

Twenty mixed‐breed dressage horses (age 9 ± 4 years; height 168 ± 6 cm; weight 600 ± 63 kg; median competition level = advanced medium) were tested at collected and medium/extended trot (age and training level dependent) in a straight line on an artificial surface ridden by their own rider at sitting trot. Four strides of each pace were recorded using high speed motion capture (240 Hz). Markers were placed on the horses' forelimbs at predetermined anatomical sites. Fetlock, carpus, elbow and shoulder angles were derived at midstance. Descriptive statistics and mixed effect multilevel regression analyses were performed on the data.

Results

Fetlock extension angle was significantly increased at medium compared with collected trot (coefficient: 5.70; CI 2.58–8.82; P<0.01) and extended compared with collected trot (coefficient: 8.59; CI 5.16–12.02; P<0.01). Fetlock extension angle was significantly increased when carpus extension angle (coefficient: 0.61; CI = 0.4–0.82; P<0.01) and shoulder flexion angle were increased (coefficient: 0.18; CI 0.01–0.33; P<0.05).

Conclusions

Fetlock extension increased when the horses performed lengthened trot paces, more in extended than medium trot. The loading of the carpus and shoulder were related to fetlock extension, suggesting that lengthened paces affect the loading of the entire forelimb. Lengthened paces may be contraindicated in horses with fetlock hyperextension or suspensory ligament injury; they may be a potential risk factor for these injuries. Interaction with the surface could also have a role that could be further investigated.

Ethical animal research: The study was approved by the Animal Health Trust ethical review committee. Owners gave informed consent for their horses' inclusion in the study. Sources of funding: Elise Pilkington Charitable Trust, Dr Wilfrid Bechtolsheimer, British Dressage. Competing interests: None declared.
The Effect of Obesity and Endocrine Function on Foal Birthweight in Thoroughbred Mares
Authors: Smith S. , Marr C.M. , Menzies‐Gow N.J.
Published: September 2015

Reasons for performing study

The birthweight of Thoroughbred foals has increased in recent years. It is unknown whether this is associated with increased broodmare obesity or endocrine dysfunction.

Objectives

To determine insulin, leptin and triglyceride concentrations in obese and non‐obese Thoroughbred mares throughout gestation and to investigate their association with foal birthweight.

Study design

Prospective, cohort study.

Methods

Fifty‐seven pregnant Thoroughbred mares were included in the study. From 40 days post‐breeding, body condition score (BCS), weight and venous blood samples were obtained every 60 days throughout gestation. Feed was withheld for 6 h before blood sampling. Serum/plasma insulin, leptin and triglyceride concentrations were measured using validated/standard methods. Foal birthweight was recorded. Association of hormone or triglyceride concentration with time, BCS and birthweight were analysed using a linear mixed effects model. A Pearson correlation co‐efficient was calculated between hormone or triglyceride concentration, BCS and birthweight.

Results

Serum insulin concentrations were significantly greater (P<0.05) at 0–59 days compared with 240–299 days and at 60–119 days compared with 180–359 days gestation. 55% of mares had BCS ≥ 7. There was 1.5% incidence of fasting hyperinsulinaemia throughout gestation and no association of fasting insulin concentration with BCS. Leptin concentration was significantly (P<0.0001) greater at 180–239 days compared with all other time points and was significantly (r = 0.29, P<0.0003) correlated with BCS. Triglyceride concentration was significantly (P<0.02) greater at 240–299 days compared with earlier time points but was not associated with BCS. Foal birthweight was significantly positively correlated with BCS (r = 0.13, P<0.001) and inversely correlated with leptin concentration at 60–119 days and 240–299 days gestation (r = −0.64, P<0.05).

Conclusions

Mare BCS correlated with foal birthweight such that obese mares had heavier foals. Significant fasting hyperinsulinaemia was not identified in this population. Increased leptin concentration in early and late gestation was associated with decreased foal birthweight and may be useful to predict foal birthweight.

Ethical animal research: Informed client consent was obtained for all animals used in the study. Source of funding: Private donor. Competing interests: None declared.
Effects of Time of Day, Ambient Temperature and Relative Humidity on the Repeatability of Infrared Thermographic Imaging in Horses
Authors: Satchell G. , McGrath M. , Dixon J. , Pfau T. , Weller R.
Published: September 2015

Reasons for performing study

Infrared imaging is becoming popular as an aid to traditional diagnostic tools, its repeatability under practically relevant conditions is still discussed.

Objectives

We hypothesise that time of day, ambient temperature and relative humidity affect thermography readings, and that there is no difference between values from left and right side.

Study design

Repeated thermography in a convenience sample.

Methods

Fifteen sound horses were thermographically imaged at 3 time points in the same day (08.00, 12.00 and 16.00 h). Images were taken of the following regions: neck, carpus, distolateral thoracic limbs (cranial and tendon areas), thoracolumbar, pelvis, hock and pelvic limb tendons. Relative humidity and ambient temperature were recorded for each session.

Results

There was a significant difference between the temperature readings during the 3 imaging sessions in all areas (Friedman and Kruskal–Wallis; all P<0.014). Ambient temperature and relative humidity correlated with thermography readings in the caudal imaging areas (P<0.008 [temperature], P<0.032 [humidity]) of the horses, with an exception of one hock reading, but not in all cranial areas (P<0.365 [temperature], P<0.992 [humidity]) (Spearman's Rho). All but 2 regions (minimum values in the carpus and thoracic tendon areas in the morning session, (P = 0.033, 0.034) did not show significant difference between left and right sides at the same time of day (all P>0.057).

Conclusions

Time of day, ambient temperature and relative humidity must be considered when using infrared imaging. Variations between the left and right sides of the horse can occur and should be considered during the analysis of pathological asymmetry.

Ethical animal research: Ethical approval was granted from the Royal Veterinary College Ethics and Welfare committee as part of the first and second author's final year research project. Source of funding: Funding was provided by the Royal Veterinary College as part of the first and second authors' final year research project. Competing interests: None declared.
Diffusion of Radiodense Contrast Medium after A Mid‐Pastern Ring Block
Authors: Malton R. , Nagy A.
Published: September 2015

Reasons for performing study

Diffusion of local anaesthetic solution after a mid‐pastern ring block has not been investigated.

Objectives

To demonstrate potential distribution of local anaesthetic solution following injection of radiodense contrast medium as performed for a mid‐pastern ring block.

Study design

Experimental.

Methods

Twelve mature horses were used. One and a half ml radiodense contrast medium was injected over the medial or lateral palmar digital nerve at the level of the proximal aspect of the ungular cartilages. A dorsal ring block was performed on the ipsilateral side, 1.5 cm proximal to the palpable palmar aspect of the proximal eminence of the middle phalanx, using 2 or 5 ml contrast medium. Both forelimbs were injected on 2 days (48 injections). Four standard radiographic views of the pastern were obtained immediately, 10 and 20 min after injections. Images were analysed subjectively and objectively.

Results

After dorsal injections the contrast medium was distributed in a diffuse patch over the ipsilateral half of the proximal phalanx (PP), extending proximally over the half of the length of PP in all limbs (greatest proximal extension: 89.0% of the length of PP [from distal] after 2 ml, 94.2% after 5 ml). There was significant proximal diffusion in the first 10 min after injection and significant dorsal diffusion between all time points (P<0.01). There was significant positive association between injected volume and the proximal extension of the dorsal contrast patch (P = 0.01). The median dorsal diffusion was to the dorsal midline of PP; 5 ml contrast medium resulted in significantly greater dorsal diffusion than 2 ml (P<0.01). The dorsal and the palmar contrast patches did not merge.

Conclusions

Diffusion to the proximal aspect of P1 occurred even after injection of only 2 ml contrast medium. Fetlock region pain may be influenced by a mid‐pastern ring block.

Ethical animal research: Written consent had been obtained from a representative of the horses' owner prior to starting the study. Source of funding: None. Competing interests: None declared.
The Use of Electromyography Including Interference Pattern Analysis to Determine Muscle Force of the Deep Digital Flexor Muscle in Case of Equine Laminitis
Authors: Hardeman L.C. , van der Meij B.R. , Back W. , van der Kolk J.H. , Wijnberg I.D.
Published: September 2015

Reasons for performing study

In cases of laminitis, an increased muscle force or contracture of the deep digital flexor muscle (DDFM) is suggested, but evidence‐based research is lacking.

Objectives

To test if the DDFM of laminitic equines shows an increased muscle force detectable by needle‐EMG including Interference Pattern Analysis (IPA).

Study design

Cross‐sectional study.

Methods

Three groups consisted of Group 0 (control): 6 Royal Dutch Sport horses, 3 Shetland ponies and one Welsh pony (healthy, sound adults, mean ± s.d. weight 411 ± 217 kg). Group 1: 3 Royal Dutch Sport horses, one Friesian, one Haflinger, one Icelandic horse, 2 Welsh ponies, one miniature Appaloosa and 6 Shetland ponies (adults, mean ± s.d. weight 310 ± 172 kg) suffering from acute or chronic laminitis. EMG measurements including firing frequency (F) and IPA parameters Turns/Second (T), Amplitude/Turn (M) and Ratio M/T (R) were performed. ANOVA was used to analyse data. P values of P<0.05 were considered significant.

Results

Mean ± s.d. F of Group 0 and Group 1 was 53 ± 11 and 72 ± 21 Hz, mean ± s.d. T was 112 ± 57 and 106 ± 42, mean ± s.d. M was 284 ± 51 and 254 ± 38 μV and mean ± s.d. R was 0.39 ± 0.17 and 0.42 ± 0.16%, respectively. The firing frequency of Group 1 was significantly higher compared to Group 0 (P = 0.02), whereas other differences were not significant.

Conclusions

In human medicine, an increased firing frequency is a characteristic of increased muscle force [1,2]. Thus, the increased firing frequency of the DDFM in case of laminitis suggests an elevated muscle force. As all parameters show a high variance, a repeated study including a larger test group is advised.

Ethical animal research: Data collection from controls was approved by the Animal Welfare Committee of Utrecht University, approval number 2008.III.07.061 and 2013.III.01.012. Clinical cases were privately owned and written owner consent was obtained. Source of funding: None. Competing interests: None declared.
Plant Thorn Synovitis Caused by Prunus Spinosa (Blackthorn) Penetration in 35 Horses
Authors: Ashton N.M. , Doles J.
Published: September 2015

Reasons for performing study

Blackthorn (Prunus spinosus) is recognised as causing infections and tissue reactions.

Objectives

To describe the presentation, diagnosis, treatment and outcome of blackthorn plant thorn synovitis in the horse.

Study design

Case series.

Methods

All cases in this prospective study presented with acute onset synovitis within 24 h of thorn penetration, had a standardised clinical assessment, surgical treatment and aftercare. Surgical treatment was performed within 24 h of presentation under general anaesthesia, using a 2‐stage procedure: Stage 1: perisynovial technique. Ultrasound guided placement of a 20 gauge 35 mm needle marker that is used as a guide for electrosurgical dissection onto perisynovial thorn fragments. Stage 2: endoscopic technique. Using standard and novel portals to locate and remove thorn fragments and debris from synovial structures.

Results

Thirty‐five cases met the study inclusion criteria over a 24 month period. Mean lameness score on presentation was 4/5 (range 1–5). The most commonly affected structures were fetlock joints (11/35) and tendon sheaths (10/35). Mean synovial fluid total protein was 50.5 g/l (range 18–116), and TNCC was 158 x 109 (range 21–412) on presentation and 12 x 109 (range 1–46) at 48 h post operatively. All synovial fluid cultures were negative. All horses were sound (grade 0) at 5 days post operatively and all returned to full work.

Conclusions

There are a limited number of case series of blackthorn injury in humans; however, the consensus is that surgical treatment is required for a successful outcome. The 2‐stage surgical procedure described, achieved accurate identification and removal of thorn material in all cases. In contrast to previous studies on synovial sepsis, these cases had a positive outcome despite high pre‐ and post operative synovial fluid total protein and TNCC. These findings suggest that thorn synovitis cases have a different aetiology from synovitis originating from sepsis or contamination.

Ethical animal research: The study was reviewed and approved by the Ethics Committee, School of Veterinary Medicine and Science, University of Nottingham. Owners gave informed consent for their horses' inclusion in the study. Source of funding: None. Competing interests: None declared.
Outcome and Owner Perception of Conservative and Surgical Management of Fracture of the Ulna in 20 Horses
Authors: Ladefoged S. , Wallin J. , Toth T. , Andersen P.H.
Published: September 2015

Reasons for performing study

While open reduction and internal fixation is the treatment of choice for most ulnar fractures conservative treatment is sometimes chosen due to financial constraints. Additional motives for the choice of treatment may be present, and the clients perception is therefore of interest.

Objectives

To compare survival and outcome between horses treated for an ulnar fracture, either surgically or conservatively and to assess clients perception of treatment.

Study design

Retrospective study.

Methods

Medical records and radiographs of horses treated between January 2002 and December 2012, with a diagnosis of ulnar fracture were reviewed. Information regarding short‐ (within 1 year) and long‐term (>1 year) outcome and owner satisfaction with treatment was obtained via telephone questionnaires. Differences between groups were investigated using a chi‐square or Fisher's exact test.

Results

Fracture types included 11 type 4, 7 type 5, one type 2, and one type 1b fracture. Eleven horses were treated surgically (Group 1). Nine horses were managed conservatively (Group 2). Group 1: 7/11 (64%) survived >1 year, 5/11 (45%) returned to previous athletic level. In Group 2: 6/9 (67%) survived >1 year, 4/9 (43%) returned to previous athletic level. No significant difference in outcome could be detected. There was no difference in the total treatment cost for horses that stayed at the hospital (P = 0.22). Owners in Group 1 expressed more satisfaction with the treatment than owners in Group 2. Several of the latter expressed welfare concerns regarding the prolonged stall confinement in harness involved with this treatment.

Conclusions

Veterinarians recommending therapy for cases of ulnar fractures should be aware that many can be treated surgically with a good outcome. Prolonged hospitalisation and stall confinement of horses treated conservatively was a major welfare concern of the owners interviewed and had the same total cost as surgical treatment.

Ethical animal research: Ethical review not currently required by this conference: retrospective clinical study. Explicit owner informed consent for inclusion of animals in this study was not stated. Source of funding: None. Competing interests: None declared.
A Preliminary Study of the Effect of Manual Chiropractic Treatment on the Splenius Muscle in Horses When Measured by Surface Electromyography
Authors: Langstone J. , Ellis J. , Cunliffe C.
Published: September 2015

Reasons for performing study

A quantifiable measure of muscle activity related to the cervical spine may provide further understanding and evidence based support for chiropractic techniques. Surface electromyography (sEMG) is a noninvasive method of measuring muscle activity of the splenius muscle when the horse is at rest.

Objectives

To determine if there is a relationship between objective measurable muscle parameters and misalignments and muscle tension in the equine cervical spine.

Study design

Controlled paired randomised study.

Methods

Privately owned horses (n = 14), of mixed sex, age and mean height 157.8 cm were selected and assigned a group by matching work, management regime, age, sex and breed. The treatment group (n = 7) underwent manual chiropractic treatment following palpation. The control group underwent palpation only. A Delsys 4 sensor system was used for data collection. Probes were positioned on the muscle halfway between C1/C2 joint and the crest on the left and right sides, between the tendon insertion and the motor point to maximise signals. sEMG readings were taken at immediately before (0) and after palpation (PP) and 30 min later (30). Data were tested for normality and variance by one‐way ANOVA and paired t test.

Results

Post treatment, there was a significant decrease (P<0.01) in sEMG activity for treatment group at 0 to 30 and PP to 30. There was a significant decrease (P<0.05) in sEMG for right side for treatment group at 0 to 30 and PP to 30. There were no such significant effects for the control group. The majority (83%) of horses had atlas rotation and tilt to the right.

Conclusions

This preliminary study supports use of sEMG as a means of assessing muscle activity of equines and suggests a statistically significant reduction in splenius muscle activity is observed following manual chiropractic treatment although the benefit to the horse is unknown.

Ethical animal research: The study protocol was reviewed by the College Research Ethics Committee before commencement of the study. Owners gave informed consent for their horses' inclusion in the study. Source of funding: McTimoney College of Chiropractic assisted with the hiring of the equipment. Competing interests: None declared.
A Comparison of A 4% Modified Fluid Gelatin and A 6% Hydroxyethyl Starch on Haemodilution, Colloid Osmotic Pressure, Haemostasis and Renal Parameters in Healthy Ponies
Authors: Gratwick Z. , Viljoen A. , Page P.C. , Goddard A. , Fosgate G.T. , Lyle C.H.
Published: September 2015

Reasons for performing study

Adverse effects on renal health and haemostasis have been documented in human patients administered hydroxyethyl starches (HES). Gelatins could provide useful substitutes for HES should similar adverse effects be identified in horses.

Objectives

To compare the effects of a 4% modified fluid gelatin (MFG) with a 130/0.4 6% tetrastarch (TES) on haemodilution, colloid osmotic pressure (COP), haemostasis and renal parameters in healthy ponies.

Study design

Randomised crossover.

Methods

Three treatments (A = 10 ml/kg bwt TES, B = 10 ml/kg bwt MFG and C = 20 ml/kg bwt MFG) were administered to 6 healthy ponies with a one‐week washout period. Packed cell volume (PCV), total serum protein (TSP), COP, platelet count, fibrinogen, prothrombin time (PT), activated partial thromboplastin time (aPTT) and thromboelastography (TEG) were measured at baseline and at multiple time points up to 24 h post infusion. Serum creatinine, urine specific gravity (USG), urine protein:creatinine (UPC), urine GGT:creatinine (UGC) and urine sediment examination (USE) were performed before and 24 h after each treatment, and one week after the final treatment.

Results

All treatments caused significant haemodilution and increases in COP with treatment C having a significantly greater effect on PCV than other treatments. The platelet count decreased with all treatments and was significantly lower for treatment C compared with treatment B. No significant differences were observed in any TEG parameter within or between treatments. No significant differences in PT, aPTT or fibrinogen were observed between treatments. Serum creatinine, UGC and UPC did not change significantly pre‐ and post study. USG and USE remained within normal limits.

Conclusions

4% MFG could be considered as an alternative to 130/0.4 6% TES for volume expansion and oncotic support. Neither MFG nor TES were associated with clinically significant adverse effects on haemostasis or renal parameters.

Ethical animal research: This research was approved by the University of Pretoria's Animal Ethics Committee. The animals used in the study were part of a research herd belonging to The University of Pretoria. Sources of funding: The Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, The Abe Bailey Trust Fund, The South African Veterinary Foundation and The South African Equine Veterinary Association. Competing interests: None declared.
Accuracy and Complication Rates of Maxillary Nerve Blocks: A Comparison of Techniques Using Surface Landmarks, Ultrasound and GPS‐Guidance
Authors: Cordner B. , Dixon J. , Witte T.
Published: September 2015

Reasons for performing study

Perineural analgesia of the equine maxillary nerve is used for diagnostic and surgical procedures. Little data exists to evaluate accuracy and complication rates with current techniques.

Objectives

This study compared 2 previously described approaches to maxillary nerve analgesia, and a novel needle guidance positioning system (SonixGPS™, Ultrasonix Medical Corporation, Richmond, British Columbia, Canada), assessing relative accuracy and complication rates of each method when performed by inexperienced operators.

Study design

Cadaver study.

Methods

Clinical veterinary students performed surface landmark, ultrasound and GPS guided contrast injections, to simulate maxillary nerve blocks in 38 equine cadaver heads. Computed tomography was then used to assess accuracy (successful deposition of contrast in contact with the maxillary nerve), and complication rate (contrast identified within surrounding vasculature or periocular structures), associated with each method.

Results

Perineural injection of contrast around the maxillary nerve was attempted 76 times, with an overall success rate of 65.8% (50/76), and complication rate of 53.9% (41/76). Success rates were 50% (13/26) with surface landmark, 65.4% (17/26) with ultrasound and 83.3% (20/24) with GPS guided approaches (Fisher's exact P = 0.046). No significant difference in complication rate was found between the 3 methods.

Conclusions

Ultrasound guided maxillary nerve blocks are significantly more accurate than surface landmark approaches when performed by inexperienced operators, and best success rates are achieved with GPS needle guidance. All 3 methods were equivalent in terms of complication rates when performed in cadavers.

Ethical animal research: This study was authorised by the Ethics and Welfare Committee of the Royal Veterinary College. The study was performed on material obtained from abattoirs. Source of funding: Royal Veterinary College. Competing interests: None declared. Acknowledgements: We thank the technical teams of the Equine Referral Hospital Diagnostic Imaging and Pathology departments and the clinical veterinary students.
Detection of the Toxin Hypoglycin A in Pastured Horses and in the European Sycamore Maple Tree (Acer Pseudoplatanus) During Two Outbreaks of Atypical Myopathy in Sweden
Authors: Gröndahl G. , Berglund A. , Skidell J. , Bondesson U. , Salomonsson M.
Published: September 2015

Reasons for performing study

Hypoglycin A (HG) appears to cause atypical myopathy (AM), but to our knowledge, detection of HG in affected and unaffected horses and concurrently in plants that they were exposed to has not previously been reported.

Objectives

To investigate HG in samples from horses exposed to Acer pseudoplatanus (European sycamore maple) and in such plant material, at the time of clinical cases of AM in the herd.

Study design

Cross‐sectional study.

Methods

Blood was collected from 2 horses with AM and 22 clinically healthy co‐grazing horses in 2 Swedish farms within one week of onset of signs (May 2014) and one month later, after horses were moved to other pastures. Ten healthy control horses from unaffected farms were sampled once. Samaras, seedlings, flowers and leaves from Acer pseudoplatanus and from Acer platanoides L (Norway maple) were collected from affected pastures. Hypoglycin A was analysed using chemical derivatisation with dansyl chloride (DNS) and ultra high performance liquid chromatography–tandem mass spectrometry. Hypoglycin A was detected as derivatised compound HG‐DNS [M+H]+ with selected reaction monitoring.

Results

Hypoglycin A was detected in the horses affected with AM, and also in 20 out of 22 co‐grazing horses. One month later, a surviving case horse and 9/20 co‐grazing horses were still positive for HG. Controls from other farms were negative for HG. Hypoglycin A was detected in plant material from Acer pseudoplatanus, but not from Acer platanoides L.

Conclusions

Horses grazing in pastures with HG‐containing Acer pseudoplatanus were positive for HG in blood, and some showed severe signs of myopathy.

Ethical animal research: Ethical consent for blood sampling was granted (C113/11) and horse owners gave their informed consent to inclusion of horses in the study. Source of funding: National Veterinary Institute, Sweden. Competing interests: None declared.
Antimicrobial Sensitivity of Bacteria Isolated from Neonatal Foal Samples in New Zealand (2004 to 2013)
Authors: Toombs‐Ruane L.J. , Riley C.B. , Rosanowski S.M. , Kendall A.T. , Hill K.E. , Benschop J.
Published: September 2015

Reasons for performing study

Guidelines for the rational use of antimicrobials enable practitioners to improve antimicrobial stewardship and slow the development of antimicrobial resistance (AMR) [1]; these must be regionally relevant [2]. New Zealand (NZ) is geographically isolated and the importance of AMR on equine studs is unknown.

Objectives

To identify AMR patterns of bacteria isolated from NZ foals so as to provide regionally specific information for the development of antimicrobial stewardship guidelines.

Study design

Retrospective study of clinical pathology records.

Methods

A database search of bacterial culture submissions from foals <3 weeks of age from April 2004 to December 2013 was completed. Culture results, antimicrobial sensitivities, and demographic factors were tabulated. The Kirby‐Bauer disk diffusion susceptibility test was used to define sensitivity. Multi‐drug resistance (MDR) was defined as non‐sensitivity to 3 or more core antimicrobials in a panel (ceftiofur, enrofloxaxin, gentamicin, penicillin [not included for Gram‐negative bacteria], tetracycline, trimethoprim‐ sulfamethoxazole).

Results

Bacterial isolates (n = 127) were cultured from 64/102 (62.7%) of foal submissions. Four bacterial groups (Staphylococcus spp., Streptococcus spp., Enterococcus spp. and Escherichia coli) accounted for 100 (79%) of bacterial isolates cultured. At least one or 2 MDR isolates were cultured from 24 (38%) and 8 (12%) foals, respectively. Culture positive and negative foals were demographically similar.

Conclusions

A significant number of bacterial isolates from foals have reduced antimicrobial susceptibility to commonly used antimicrobial drugs. The results are of concern from treatment and stewardship perspectives. Multi‐drug resistance was found, indicating a need for regionally relevant antimicrobial use recommendations.

Ethical animal research: Not applicable. Sources of funding: Massey University McGeorge fund; New Zealand Equine Research Foundation. Competing interests: None declared.
Expression of Insulin‐Related Genes and Release of Non‐Essential Fatty Acids (Nefa) From Neck Crest Fat Compared to Abdominal, Mesenteric, and Tail Pad Fat in Horses
Authors: Bernhardsson M.G. , Berg L.C.
Published: September 2015

Reasons for performing study

Regional adiposity on the neck crest has been linked to increased risk of developing equine metabolic syndrome (EMS). However, little is known about inherent metabolic differences between adipose tissues.

Objectives

To investigate innate differences between adipose tissue from neck crest compared to abdominal, mesenteric, and tail head in horses with no diagnosis of EMS.

Study design

Cross‐sectional study.

Methods

Seven horses with no history of metabolic disorders were subjected to euthanasia for nonclinical reasons. They were selected randomly (5 geldings/2 mares; age 6–26 years; 110–165 cm height; BCS 3–8) and included with owners' consent. Adipose tissue was collected from neck crest, abdominal tissue, small intestine mesentery, and tail pad. mRNA expression of insulin‐associated genes GLUT1, GLUT4, INSR and RBP4, and inflammation‐associated genes SAA, TNFα, IL‐1β, IL‐6, MCP‐1 and PAI‐1 were investigated using RT‐qPCR. Morphology and adipocyte size were investigated by histology. Release of non‐essential fatty acids (NEFA) was investigated before/after adrenaline stimulation in 4 horses.

Results

No significant differences were found in mRNA expression of metabolic and inflammation related genes between tissues. Adipose tissue from neck crest was more heterogeneous than abdominal fat (P = 0.001) and mesenteric fat (P = 0.01). Neck crest adipocytes were similar in size to abdominal adipocytes, and larger than adipocytes from tail head and mesentery. Basal levels of NEFA release were not different between tissues. Adrenaline stimulation caused a significant release of NEFA from visceral fat (abdominal P = 0.03; mesenteric P = 0.048).

Conclusions

This preliminary study introduces new metabolic genetic markers and NEFA to the field of metabolic research. No innate differences were shown for neck crest fat except in histology. Further studies in a case–control study design are needed to determine if neck crest fat is a risk factor for EMS.

Ethical animal research: Horses were subjected to euthanasia according to Danish Law and Danish ethical regulatory guidelines. Samples were used for research purposes with owners' consent. Source of funding: Hesteafgiftsfonden (Danish Horse Levy Board). Competing interests: None declared.
Informed Hypothetico‐Deductive Reasoning Based on Clinical Signs for Diagnosis of Equine Laminitis Using Decision Tree Analysis
Authors: Wylie C.E. , Shaw D.J. , Verheyen K.L.P. , Newton J.R.
Published: September 2015

Reasons for performing study

Effective diagnosis of equine laminitis is necessary to allow prompt instigation of palliative and therapeutic treatments, yet there has been limited work regarding diagnostic accuracy.

Objectives

To compare the prevalence of clinical signs in laminitis and non‐laminitis lamenesses to evaluate the capabilities of discrimination for differential diagnosis.

Study design

Analytical epidemiological study.

Methods

Veterinary practitioners completed a pre‐designed checklist of laminitis‐associated clinical signs identified by literature review, for equine lameness of any origin. A case was defined as a horse/pony with veterinary‐diagnosed, clinically apparent laminitis, attended by a participating practitioner. Associations between clinical signs and case/control status were tested by logistic regression with adjusted odds ratios and 95% confidence intervals, with veterinary practice as a fixed effect, and Wald P‐value calculated. Multivariable analysis using graphical classification tree‐based statistical models allowed comprehension of the prevalence in the data associated with particular clusters of clinical signs.

Results

Data were collected for 588 laminitis cases and 201 non‐laminitis lamenesses. The overall prevalence of specific clinical signs ranged from 2.7% for ‘sole prolapse’ to 85.0% for ‘lame at trot’. Differences in prevalence ranged from −14.1% for ‘lame at trot’ (more common in controls) to +71.9% for ‘short stilted gait at walk’ (more common in cases). Five clinical signs had a difference in prevalence of greater than +50%: ‘reluctance to walk’, ‘short, stilted gait at walk’, ‘difficulty turning’, ‘shifting weight’ and ‘increased digital pulse’. Bilateral forelimb lameness was the best discriminator (92% of animals with this clinical sign had laminitis). The additional presence of increased digital pulses improved this to 99%. Flat/convex sole, shifting weight and short stilted gait at walk were also useful discriminators.

Conclusions

This is the first study to provide information aiding diagnostic hypothetico‐deductive reasoning based on clinical signs to differentially diagnose laminitis from other lamenesses.

Ethical animal research: Ethical approval obtained from Royal Veterinary College. Owners gave informed consent for their horses' inclusion in the study. Sources of funding: Project funded by World Horse Welfare. C.E. Wylie currently funded by The Margaret Giffen Charitable Trust. Competing interests: None declared.