bluuebunny/crossref_metadata_2025 huggingface dataset:
Vertical Displacement of the Equine Pelvis When Trotting on an Aqua Treadmill
Authors: York J , Walker A
Published: June 2014

Introduction

Hydrotherapy is increasingly applied within the equine industry for rehabilitation and therapy. Substantial anecdotal evidence exists suggesting the benefits of its application but while there is extensive literature on the use of aqua‐treadmills in humans and canines there is comparatively little in equines. Therefore, limited research exists supporting the role of the aqua‐treadmill in current therapy practices. This study aimed to investigate the effect of water depth on pelvic movement during aqua‐treadmill exercise.

Methods

Eight horses were trotted on an aqua‐treadmill at four water depths specifically measured to individual horses (P3, fetlock, MC3, carpus). Pelvic displacement was recorded using an optical motion capture system to collect coordinates from markers placed on the tuber sacrale, tuber coxae, withers and lumbar spine. Data were processed using custom written scripts (Matlab®) and ANOVA was performed.

Results

All subjects demonstrated a significant increase in vertical displacement of the pelvis as water depth increased from P3 to carpus while displacement symmetry was not significantly altered with a change in water depth.

Conclusions

The common practice of increasing water depth to intensify the physical demands of the exercise while maintaining the desired movement symmetry is supported. Having knowledge of how a horse moves on an aqua‐treadmill is vital for tailoring specific therapy in order to most successfully rehabilitate the horse from injury. Investigation of the effects of increasing water depth on asymmetric horses should be carried out to further support its application as a tool for rehabilitation.

Ethical Animal Research

Ethical approval was obtained from the Ethics Review Committee at Moulton College. Owner consent was granted for all subjects and all horses were handled in compliance with British Horse Society standards throughout the trials. Sources of funding: Thomas Harrison Trust at Moulton College. Competing interests: none.
The Impact of Playing Strategies on Recovery in Low‐Goal Polo‐Ponies
Authors: Fiander A , Williams J
Published: June 2014

Introduction

Polo is a popular sport; teams compete in matches comprising 4–6 chukkas, each between 7–10 minutes. Players commonly change ponies between chukkas, but changing within a chukka, known as ‘half‐chukkering’ is permitted. This is believed to ‘save’ the horse by preventing fatigue and facilitating recovery. This study evaluated the impact of half versus full chukka playing strategies in low goal polo; team handicap 0–4 goals.

Methods

Resting heart rates (HR) were established for 48 polo‐ponies deemed of comparable fitness by riders, competing in low‐goal tournaments; riders selected their playing strategy either full‐chukka (n = 32) or half‐chukkering (n = 16). HR was recorded at the end of play and during recovery; for the full‐chukka and 2nd half‐chukka period at +2, 4, 6, 10 and 20 minutes, and until ponies returned to play after the 1st half‐chukka, >6 minutes. ANOVA analyses investigated HR variation during recovery between ponies playing full‐chukkas and the 2nd half‐chukka period, and within the two half‐chukkas played.

Results

At the end of play, full‐chukka horses′ mean HR were 95 ± 13.1 bpm, compared to their 2nd half‐chukka counterparts at 103 ± 7.7 bpm, which was not significant. Significant differences in HR did occur throughout the subsequent recovery period: at 2 minutes (P<0.003) and between 4–20 minutes (P<0.0001), with full‐chukka ponies recovering faster. No differences occurred during recovery between the two half‐chukka periods although mean HR differed at the end of play (1st: 100 ± 7.7 bpm; 2nd: 103 ± 7.8 bpm).

Conclusions

Playing strategies influence cardiovascular recovery; full‐chukka ponies recover faster than those playing in consecutive half‐chukkas. Preparation of half‐chukka ponies may predispose to reduced fitness levels compared to full‐chukka ponies. Implementing a full‐chukka playing strategy is advocated to optimise pony welfare and performance in low‐goal polo.

Ethical Animal Research

Ethical approval for the study was granted from the UWE Hartpury Ethics Committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: none. Competing interests: none.
Quantification of Energy Expenditure in Field Conditions: Comparison of Direct VO2 Versus VO2 Estimation from Heart Rate Measurements
Authors: Fortier J , Goachet A , Deley G , Julliand V
Published: June 2014

Introduction

In humans, oxygen consumption (VO2) and heart rate (HR) are commonly used to assess energy expenditure (EE) during exercise in field conditions. We hypothesized that the estimation of EE from HR measurements could be a relevant parameter to estimate EE during submaximal field exercise. This study aimed to compare the EE from VO2 and HR measurements in exercising trotters.

Methods

Six harnessed French Trotters were submitted to a continuous field incremental test (FIT) at trot to establish their individual VO2/HR relationship. Then they undertook a submaximal exercise bout (EX) over 2375 m during 3.41 ± 0.47 min at 70% of maximal velocity. VO2 and HR were recorded continuously (equine K4b2, COSMED, Rome, Italy) throughout FIT and EX. EE of EX was calculated by multiplying the total VO2 (Liters), either directly measured or predicted from HR, with its caloric equivalent (4.86 kcal/liter). Means were compared using a Student's t test.

Results

EE of EX was estimated at 2422 ± 390 kcal and 2630 ± 706 kcal from direct VO2 and HR methods respectively (P = 0.54).

Conclusions

We found no significant difference between the two methods for estimating EE of submaximal exercise. This suggests that the prediction of EE from HR monitoring might be used to evaluate EE of moderate intensity workouts.

Ethical Animal Research

The project was conducted under the ethics committee approval B1110. Sources of funding: INRA PHASE, the Burgundy Region and AgroSup Dijon. Competing interests: none.
Value of Field Trials to Investigate Poor Performance in Sport Horses
Authors: Van Erck Westergren E
Published: June 2014

Introduction

In equestrian sports where horses exercise at submaximal levels, the identification of some clinical conditions leading to poor performance can remain difficult. The aim of this study was to design a graded exercise test, applicable in the field and to test the hypothesis that measured heart rate (HR) and lactate (LA) differ between healthy and subclinically‐affected horses, according to diagnosis.

Methods

Fifty‐four sport horses regularly participating in competitions were studied. A total of 106 examinations were performed, 85 were poor performance investigations (PP) and 21 were controls (C) in healthy performing individuals. The exercise test consisted of 4 consecutive 2‐minute steps, 2 at trot and 2 at canter. Heart rate (HR), ECG and lactate (LA) were recorded. Blood samples, tracheal wash and bronchoalveolar lavage were systematically collected. Other examinations were performed when indicated. Differences in HR and LA between groups were compared using an ANOVA. Repeatability was checked in 12 horses.

Results

Tests were highly reproducible. Diagnoses included upper (15%) and lower (48%) respiratory, cardiac (12%), locomotor (25%), and muscular (17%) disorders. Although horses did not systematically exceed the lactate threshold, HR and LA at steps 2, 3 and 4 and recovery HR differed significantly between groups (P<0.001–0.03). The rate of increase in LA and HR varied according to diagnosis, with LA reaching significantly higher values in horses affected with cardio‐respiratory conditions.

Conclusions

Field exercise testing in sport horses during the competitive season is a simple procedure that allows an objective measurement of the horse's capacity to exercise. The analysis of HR and LA provides indications for specific diagnostic examinations and helps assess the functional impairment caused by subclinical disease.

Ethical Animal Research

This study was based on clinical cases referred to the Equine Sports Medicine Practice. Horse owners referred their horses and consented to all procedures described. Sources of funding: none declared. Competing interests: none.
Intra‐ and Inter‐Day Variability in Plasma Bicarbonate Concentration in Sedentary Horses
Authors: Bergstrom B , Foreman J , Foreman C , Barger A
Published: June 2014

Introduction

Alkalinizing agents have been given to horses before exercise to provide exogenous buffering effects. The objective of this experiment was to determine the intra‐ and inter‐day variability of resting plasma tCO2. The hypothesis was that tCO2 would vary measurably during a multi‐day quarantine.

Methods

Eight acclimated sedentary horses had jugular venous samples collected into 10‐ml heparinized evacuated glass tubes 3 times daily (7 AM, 11 AM, and 3 PM) for 5 consecutive days. Horses ate 5.3 kg alfalfa hay at both 7 AM and 3 PM after blood sampling. Plasma tCO2 was determined within 1–3 hours of sampling using an automated chemistry analyzer. Mean tCO2 for all 8 horses was calculated for each of the 15 sampling intervals. Results were compared by Repeated Measures ANOVA. When there was no apparent day‐to‐day effect, data for all horses were pooled by time‐of‐day (n = 40 samples for each of 3 times‐of‐day) and compared by the Student's t test to determine time‐of‐day effect. P<0.05 was considered significant.

Results

Mean tCO2 over the 15 sampling intervals ranged from 28.9‐to‐31.6 mmol/L and was lower at 11 AM (Day 1) and 3 PM (Days 1, 3, and 4) compared to 7 AM on Day 1 (P<0.05). Individual plasma tCO2 ranged over 4‐to‐7 units (low 26, high 34, widest range 26–32, narrowest 28–31). Mean pooled tCO2 differed by time‐of‐day, with 11 AM (30.1 ± 0.2, P = 0.011) and 3 PM (29.8 ± 0.2, P<0.001) values lower than 7 AM values (31.0 ± 0.2).

Conclusions

Plasma tCO2 differed significantly by time‐of‐day with considerable intra‐ and inter‐individual variability.

Ethical Animal Research

The study was approved by the University of Illinois Institutional Animal Care and Use Committee. Sources of funding: Fédération Equestre Internationale and Maria Caleel Fund for Equine Sports Medicine Research. Support for Dr. Bergstrom was provided by the Merial Veterinary Scholars Program. Competing interests: none.
Lactate Transport in Red Blood Cells by Monocarboxylate Transporter MCT1 and Its Accessory Protein CD147 In Brazilian Sport Horses of Different Performance Levels
Authors: Feringer Junior WH , Carvalho JRG , Almeida MLM , Queiroz‐Neto A , Ferraz GC
Published: June 2014

Introduction

The Brazilian sport horse (BH) was specifically developed for jumping competition. Monocarboxylate transporters are key regulators of cell pH and therefore facilitate co‐transport of protons and lactate. Lactate transport in red blood cells (RBCs) is bimodal (high [HT] and low transport [LT]) and is related to CD147 levels. This study aimed to quantify MCT1 and CD147 protein levels in BH after an incremental jumping test (IJT).

Methods

Sixteen horses were distributed into two groups: low‐level jumpers (LL, n = 8), able to jump up to 1.00 m, and high‐level jumpers (HL, n = 8), able to jump up to 1.20 m. The IJT consisted of three steps, each with forty jumps at increasing heights (0.40, 0.60, and 0.80 m). Blood samples were collected before and after the IJT. The YSI 2300 method was used to determine plasma lactate concentration [Lac]p. RBC membranes were purified, and MCT1 and CD147 levels were measured by Western blotting. A Student's t‐test and Pearson's correlation (P<0.05) were employed.

Results

The HL group displayed lower [Lac]p, indicating prevalence of the aerobic pathway in this group. The results showed no difference in the expression of the transporters between times or groups and a positive correlation (r = 0.67, P<0.0001) between MCT1 and CD147. In both groups [Lac]p didn't correlate with the amount of MCT1 or CD147. Most of the horses appeared to have high lactate transport activity. The CD147/MCT1 ratios for LL and HL were equal.

Conclusions

BH showed no difference in MCT1 and CD147 expression between conditioning levels.

Ethical Animal Research

All procedures were approved by the institutional animal care and use committee of the university (CEUA, Process: 019281/13). Explicit owner informed consent for participation in this study is not stated. Sources of funding: FAPESP ‐ Fundação de Amparo à Pesquisa do Estado de São Paulo (Process 2011/11080‐0). Competing interests: none.
“Positive” Plasma tCO2 Tests in Racehorses in New York, Maine, and California Result from Day‐to‐Day Instrument Variability
Authors: Foreman J , Foreman C
Published: June 2014

Introduction

Many jurisdictions measure plasma tCO2 to determine if racehorses may have been administered exogenous alkalinizers illegally (“milkshakes”). Our hypothesis was that plasma tCO2 test results vary within a racing jurisdiction due to inter‐day instrument variability.

Methods

Individual or daily mean plasma tCO2 test results from New York (n = 584) and Maine (n = 443) Standardbreds and California Thoroughbreds (n = 23,686) were obtained through legal discovery in adjudicated cases where trainers were accused of tampering with horses resulting in tCO2 concentrations ≥37.0 mmol/L. Daily results were grouped by days on which no horse tested ≥37.0 mmol/L (LOW) or days on which at least one horse tested ≥37.0 mmol/L (HIGH). HIGH days were further subsampled by eliminating “positive” test results ≥37.0 mmol/L (MODIFIED HIGH). With P<0.05 considered significant, differences between groups were compared by Student's t test for means and Mann‐Whitney Rank Sum Test for medians.

Results

HIGH tCO2 means (32.9 ± 2.6, 35.2 ± 3.4, 32.6 ± 2.7) and medians (32.9, 35.4, 32.6) for all 3 jurisdictions were higher than LOW means (31.7 ± 2.3, 31.9 ± 4.3, 31.5 ± 0.7) and medians (31.8, 32.9, 31.5) (P<0.001). Even when “positive” tests ≥37.0 were eliminated, MODIFIED HIGH means (32.5 ± 2.2, 33.6 ± 2.6, 32.4 ± 2.5) and medians (32.7, 34.2, 32.5) were still higher than LOW (P<0.001).

Conclusions

Unless the population tCO2 mean varies significantly daily, it must be concluded that instrument variability resulted in day‐to‐day differences in plasma tCO2 test results. Without appropriate quality control including correction of individual suspect results to a contemporaneous standard curve, horse trainers may be accused unfairly of tampering when day‐to‐day instrument variability contributes to positive plasma tCO2 test results.

Ethical Animal Research

This was a retrospective study investigating laboratory results obtained through adjudication of legal cases before various racing commissions. Sources of funding: none. Competing interests: none.
Preliminary Results on CD147 Expression in Red Blood Cells of Arabian Horses
Authors: Regatieri IC , Almeida M LM , Teixeira Neto AR , Ferraz GC , Queiroz‐Neto A
Published: June 2014

Introduction

During anaerobic glycolysis for energy production, lactate and H+ ions accumulate in muscle fibers and pass into the bloodstream. Monocarboxylate transporter type 1 and its ancillary protein CD147 transport H+ and lactate ions from the plasma into red blood cells, thereby maintaining acid/base homeostasis and retarding systemic acidosis and fatigue. The aim of this study was to compare the levels of CD147 protein in the red blood cells of Arabian horses with different levels of athletic ability.

Methods

Blood samples were taken from 12 Arabian horses before exercise. The horses were divided into two groups: untrained horses (UH, n = 6) and 160‐km endurance horses (FEI, n = 6). The amount of CD147 in the plasma membranes of their red blood cells was determined by Western blotting analysis using a human‐specific anti‐CD147 antibody previously validated for horses. The medians were compared by Mann‐Whitney Rank Sum test at 5%.

Results

CD147 protein with a molecular mass of approximately 45 kDa was found in the red blood cell membranes of the studied horses. The CD147 expression levels of the two groups were not different (P = 0.065). The observed median values (min–max) were 0.50 (0.37–1.26) and 0.27 (0.09–0.69) arbitrary optical density units for the FEI and UH group respectively.

Conclusions

Studies must be performed with more horses to determine if a different level of CD147 expression exists in FEI horses related to their intensive training programs or to the genetic traits of each horse.

Ethical Animal Research

All procedures were approved by the institutional animal care and use committee of the university (CEUA, Process: 019314/13). Explicit owner informed consent for participation in this study is not stated. Sources of funding: FAPESP ‐ Fundação de Amparo à Pesquisa do Estado de São Paulo. Process: 2012/24193‐0. Competing interests: none.
Real‐Time Monitoring of the Core Body Temperature of Endurance Horses During Field Exercise
Authors: Verdegaal E , Jonas S , Caraguel C , Franklin S
Published: June 2014

Introduction

Continuous monitoring of core body temperature may provide useful information about the thermal response to metabolic heat load and environmental challenges. The aim of this study was to evaluate a telemetric gastrointestinal (GI) pill (Equivital®) measuring gastrointestinal temperature (GT) during endurance exercise. It was hypothesised that a temperature and metabolic heat profile could be established.

Methods

TheGIpill was administered to 6 horses by nasogastric tube (n = 3) or modified‐drench gun (n = 3), the day before competition. During competition,GT, skin temperature and heart rate (HR) were recorded (by Equivital® belt). Other data collected included body weight and rectal temperature (RT),GPS/HRmonitor information, and environmental conditions using a data logger. Metabolic heat production was calculated [1] andGTcorrelations were explored using simple correlation estimates (P<0.05).

Results

Data were collected from 6 horses during 80 km (n = 4 horses) and 100 km (n = 2) competition days with mean data loss of 7.4% (±2.4%).GTprofiles showed increasing temperature with cumulative metabolic heat production, and time to reach maximumGTwas 2.14–6.29 h (maximumGTrange: 38.4–39.5°C). During exercise (7 h 6 min ± 1 h 3 min duration), mean and maximum speeds ranged from 10.1–14.5 km/h and 23.5–30.8 km/h, respectively. No correlation was found betweenGTandHR, skin, or environment temperature. MaximumGTincreased with bodyweight (r = 0.775, P = 0.08).GTwas systematically higher thanRT(mean difference +0.46°C).

Conclusions

GTwas recorded successfully during competition with minimal data loss. TheGIpill has great potential as a method to further investigate thermoregulation in horses under field conditions.

Ethical Animal Research

All studies were performed under the AdelaideAnimalEthicsCommittee,University of Adelaide.Explicit owner informed consent for participation in this study is not stated.Sources of funding: The equipment for the project was funded by the Faculty of Science ‘Grant for minor equipment’,University of Adelaide,Australia.Competing interests: none.
Pre‐Race Administration of Furosemide Induces a Linear Dose‐Dependent Increase in Plasma Total CO2 Concentration in Thoroughbred Racehorses
Authors: Demaree A , Couetil L , Constable P
Published: June 2014

Introduction

Furosemide is widely administered in North America for the prophylactic treatment of exercise‐induced pulmonary hemorrhage. Plasma total CO2 concentration (ctCO2) provides a clinically useful screening test for the presence of metabolic acid‐base disturbances, including the pre‐race administration of alkalinizing agents to racehorses. Some racing jurisdictions account for the metabolic alkalosis and increased plasma ctCO2 induced by furosemide administration. The purpose of this study was to determine the relationship between pre‐race furosemide dose and pre‐race plasma ctCO2 in Thoroughbred racehorses.

Methods

Jugular venous blood was collected anaerobically into 3 mL partially evacuated plastic tubes containing lithium heparin from 226 Thoroughbred horses administered a variable dose of furosemide (150–500 mg IV, n = 217) 3–4 hours previously or not administered furosemide (n = 9).

Plasma ctCO2 was calculated from the measured values for pH and pCO2 using a blood gas and pH analyzer [Radiometer ABL 700] and the Henderson‐Hasselbalch equation. Data was analyzed using multivariable linear regression and P<0.05 was significant.

Plasma ctCO2 in mmol/L increased linearly (P = 0.0006) with furosemide dose in milligrams adjusted for sex (female, stallion, gelding), such that ctCO2 = 33.38 − 0.71(if female) − 0.63(if stallion) + 0.0040 × (furosemide dose).

Conclusions

Intravenous administration of furosemide (150–500 mg) produces a linear dose‐dependent increase in ctCO2 in plasma. High intravenous doses of furosemide (500 mg) have the potential to increase plasma ctCO2 to near the threshold value used to identify the pre‐race administration of alkalinizing agents. This finding supports an allowance of 2.0 mmol/L for furosemide administration used by some racing jurisdictions in North America.

Ethical Animal Research

Samples and data were collected during race day procedures currently in place. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Indiana Horse Racing Commission. Competing interests: none.
Experimental Determination of the Apparent Value for the First Dissociation Constant (pK1′) of the Plasma Carbonic Acid – Bicarbonate Buffer System in 115 Trained Standardbreds
Authors: Constable P , Tinkler S , Demaree A , Couetil L
Published: June 2014

Introduction

Calculating the total plasma concentration of carbon dioxide (ctCO2) from the results of blood gas and pH analysis assumes that the value for pK1′ is constant and approximates 6.095. The objective of this study was to verify both assumptions in equine plasma.

Methods

Duplicate jugular blood samples were collected pre‐race from 115 trained Standardbreds into 3 mL partially evacuated plastic tubes containing lithium heparin. Blood pH (pHb) and partial pressure of CO2 (pCO2) were measured in one tube using a blood gas and pH analyser (Radiometer ABL‐700). The second tube was anaerobically centrifuged and ctCO2 was measured (Beckman EL‐ISE analyser). Plasma pK1′ was calculated for each horse using the Henderson‐Hasselbalch equation, measured values for pHb, pCO2, and plasma ctCO2, and the value for the solubility of CO2 in plasma at 37C (S = 0.0307 {mmol/L}/mmHg) whereby: pK1′ = (pHb + 0.01)–log10({ctCO2‐S × pCO2}/{S × pCO2}), with the term (pHb + 0.01) representing the pH in plasma. The calculated value for pK1′ was standardized to pHb = 7.40 using the Severinghaus equation such that dpK1′/dpH = −0.044. Non‐parametric statistical procedures were used to determine the median value and 95% confidence interval (CI) for pK1′.

Results

The median value for pK1′ at pHb = 7.40 was 6.097, and the 95% CI for pK1′ was 6.063–6.123.

Conclusions

The 95% CI for pK1′ in equine plasma from trained Standardbreds is narrow and includes the assumed fixed value of 6.095. Our findings support the use of blood gas and pH analysis to calculate plasma ctCO2 in order to detect the pre‐race administration of alkalinizing agents in horses.

Ethical Animal Research

The study was approved by the Institutional Animal Care and Use Committee at Purdue University. Sources of funding: Supported, in part, by a grant from the Indiana Horse Racing Commission. Competing interests: none.
The Prevalence of Abnormal Breathing Patterns During Exercise and Associations with Dynamic Upper Respiratory Tract Obstructions
Authors: Fitzharris L , Franklin S , Allen K
Published: June 2014

Introduction

During canter and gallop most horses maintain a locomotor‐respiratory coupling (LRC) ratio of one breath every stride. Occasional big respiratory cycles (BRC) are described when a single breath is taken over two strides. This is considered a transient but normal feature of ventilation. However, a change to a more persistent 2:1 LRC ratio is considered to be ‘abnormal’. It has been suggested that upper respiratory tract (URT) disorders could result in a horse adopting an abnormal breathing pattern, although current information is limited.

Methods

Simultaneous audio and URT endoscopy recordings from 365 horses referred for treadmill evaluation were analysed. Breathing pattern at canter and gallop was categorised at each one minute speed step:

Normal: 1:1 with <2 BRC

Normal: 1:1 with 2 BRC

Abnormal: breathing pattern disrupted by repetitive and frequent BRC's

Abnormal: alternating between periods of 2:1 and 1:1

Abnormal: 2:1 throughout

Data analysis was performed using PASW 18.0. A chi‐square test was used to identify associations between breathing pattern and presence of URT obstructions.

Results

During the entire exercise test 30% of horses had an abnormal breathing pattern at canter or gallop, of which 23% had a 2:1 breathing pattern. The prevalence of abnormal breathing patterns was higher at low canter speeds than during strenuous exercise. There was a significant association between breathing pattern during strenuous exercise and the presence of an URT obstruction (P = 0.008).

Conclusions

Loss of a 1:1 LRC ratio during canter and gallop is more common than previously realised and may be associated with dynamic URT obstructions.

Ethical Animal Research

Retrospective analysis of case records. Sources of funding: none declared. Competing interests: none.
Big Respiratory Cycles During Treadmill Exercise
Authors: Green C , Bayly W , Sides R
Published: June 2014

Introduction

Big respiratory cycles (BRCs) are a sporadic but normal occurrence during galloping exercise. Their relationship to performance capacity as reflected by maximal oxygen consumption (VO2max) is unclear.

Methods

7 Thoroughbreds completed multiple incremental exercise tests up to 13 m/s on a treadmill to determine their VO2max while wearing a mask that measured inspired and expired volumes (VI, VE) and VO2 on a breath‐by‐breath basis. Frequency and duration of BRCs were related to speed and VO2max using regression analysis. Numbers of BRCs for each test were counted and the duration, VI, VE and VO2 of each BRC determined and compared to the corresponding average values of the 5 breaths following the BRCs, and VO2max for the exercise bout. Significance was set at P<0.05.

Results

The frequency of BRCs was 64% when all speeds and runs were considered. The number and appearance of BRCs varied considerably between horses. BRC numbers were greatest at 6 and 13 m/s and least at 9 m/s, and significantly related by polynomial regression (r2 = 0.90). BRC duration was not related to breathing frequency when all BRCs were considered due to the existence of two distinct clusters of BRCs. The duration of those lasting <1.25 s was inversely related to speed (r2 = 0.77) as were those >1.25 s in length (r2 = 0.55). BRC VI and VE were greater than normal VI and VE and the difference increased linearly (r2 = 0.89 and 0.87, respectively) as speed increased from 6 m/s (VI: 8.0 ± 0.6%; VE: 8.9 ± 0.7% greater) to 13 m/s (VI: 42 ± 2%; VE: 57 ± 3% greater). Individual VO2max was not related to the number, length or volume of BRCs.

Conclusions

The frequency, duration and size of BRCs do not affect VO2max and vary considerably within a given treadmill test and between horses.

Ethical Animal Research

Procedures were approved by the Institutional Animal Care and Use Committee (protocol #3807). Sources of funding: Funding was provided by the home department. Competing interests: none.
Comparison of Bronchoalveolar Lavage and Tracheal Aspirate Results in 64 Non‐Thoroughbred Horses Presenting with Respiratory Signs or Exercise Intolerance
Authors: Koskinen H , Raekallio M , Rahkonen E , Rajamäki M , Mykkänen A
Published: June 2014

Introduction

It has been debated which airway sampling method, bronchoalveolar lavage (BAL) or tracheal aspirate (TA), is superior in evaluating equine respiratory disease. Most studies suggest BAL is the best sampling method due to better correlation with lung histopathology. In this study we compared BAL and TA results of athletic non‐Thoroughbred horses with chronic respiratory signs or exercise intolerance during 2009–2013.

Methods

64 horses, 2–25 years of age (16 Coldbloods, 30 Warmbloods, 11 Standardbreds, 7 ponies) with recurrent or chronic (duration >1 month) respiratory signs or exercise intolerance that were subject to both BAL and TA sampling at rest were included. Neutrophil counts >5% in BAL and >20% in TA were considered abnormal. Statistical analysis was performed with Spearman's correlation coefficient.

Results

Both BAL and TA were abnormal in 29 horses and normal in 26 horses. 7 horses had only abnormal TA and 2 horses only abnormal BAL. Correlation was found between the amount of mucus in the trachea and both BAL (P = 0.002) and TA (P<0.001) neutrophil percentage. Neutrophil (P<0.001), eosinophil (P<0.001), lymphocyte (P = 0.008) and macrophage (P = 0.004) percentages correlated between BAL and TA.

Conclusions

In our university hospital population, mucus in the trachea was a good indicator of airway neutrophilia. Unlike previous studies, in only 14% of the horses the interpretation of BAL and TA result was different with TA being slightly more sensitive at detecting neutrophilia. However, a gold standard for detecting inflammation in the equine airways is still lacking and the type and severity of the disease may greatly influence the best choice of sampling method.

Ethical Animal Research

Retrospective analysis of case records. Sources of funding: none. Competing interests: none.
Cardiac Morphology and Heart Murmurs in Elite Eventing and Dressage Horses
Authors: Wijnberg ID , Maarsse J , van Kampen W , Veraa S
Published: June 2014

Introduction

Training related cardiac adaptation is documented in Standardbreds and Thoroughbreds, including an increased incidence of AV valve regurgitation. In Warmbloods less is known about training effects on cardiac function or subclinical valve regurgitation.

Methods

Fifteen adult untrained Warmbloods (aged 3.8 ± 0.7 years) were compared with fifteen adult Warmblood eventers (aged 11.4 ± 0.9 years) competing at CIC2* (group 1, n = 5) and CCI2*, CIC3*, CCI3* and CCI4*levels (group 2, n = 9) and fifteen healthy adult Warmbloods competing at advanced dressage (group 3, n = 5), Prix Saint Georges, Intermediate or Grand Prix (group 4, n = 10) levels (mean age 10.3 ± 0.7 years). The presence of heart murmurs, valve regurgitation and echocardiographic parameters were evaluated, and training intensity was scored. A correlation was found between bodyweight and not height. Differences in cardiac morphology were compared using General Linear Models with post‐hoc Bonferroni correction (SPSS version 20), using group and bodyweight as covariates. Significance was set at P<0.05.

Prevalence of audible heart murmurs and valvular regurgitation was higher in eventers (0–20% and 29–79%, respectively and dressage horses (7–40% and 7–60%, respectively) than controls (0–20% and 7–20%, respectively). Interventricular septum in diastole (IVSd, left ventricular mass (LVM) and LV mean wall thickness (LVMWT) were greater in groups 2 and 4 than controls; group 4 also had a greater pulmonary artery diameter (PAD) and LV posterior wall (LVPWd). Group 1 showed a greater LVMWT; group 4 a greater end point septal separation (EPSS). Training intensity influenced in both categories IVSd and MWT; in eventers also the right ventricular diameter in diastole and in dressage horses also LVPWd, LVM, EPSS and PAD.

Elite eventers and dressage horses showed an increased prevalence of audible murmurs and valvular regurgitation. Cardiac adaptations resembled those associated with resistance and endurance training. Increased performance level and training intensity accompanied increased cardiac muscle thickness and volume. These effects should be considered during sales and performance evaluations.

Ethical Animal Research

Evaluated by the Animal Ethics Committee of Utrecht University and owner consent was obtained. Sources of funding: Faculty of Veterinary Medicine, Utrecht University. Competing interests: none.
Subchondral Bone Remodelling Is More Active in Resting Than Training Thoroughbred Racehorses
Authors: Holmes J , Mirams M , Mackie E , Whitton C
Published: June 2014

Introduction

Subchondral bone fatigue is an important cause of poor performance, morbidity and mortality in racehorses. Fatigued bone is repaired by remodelling, a process that is attenuated under high cyclical loads, yet the effects of training on remodelling activity in Thoroughbred racehorses is unknown. We hypothesised that remodelling rates are lower in training horses than those that are resting from training.

Methods

Sections of the palmar metacarpal condyles from Thoroughbred horses that were in race training (n = 24) or resting from training (n = 24) at the time of death were examined with light microscopy and back scattered electron microscopy (BSEM). Bone area fraction (B.Ar/T.Ar), and eroded bone surface (E.Pm/T.Ar) were measured within two regions of interest; (1) the lateral parasagittal groove (PS); and (2) the lateral condylar subchondral bone (LC). BSEM variables were analysed for the effect of group (independent samples t‐test), region (paired t‐test) and interaction with time since change in training status (general linear model). Mean ± SE are reported.

Results

For both regions of interest E.Pm/T.Ar was lower in the training horses (PS: 0.39 ± 0.06 mm−1, LC: 0.24 ± 0.04 mm−1) than in the resting group (PS: 0.65 ± 0.07 mm−1, P = 0.010, LC: 0.85 ± 0.10 mm−1, P<0.001). Lower subchondral bone porosity was observed, reflected by higher B.Ar/T.Ar in the LC of training horses (90.8 ± 0.6%) than resting horses (85.3 ± 1.4%, P = 0.0010). E.Pm/T.Ar was higher with increased duration of a training period in the lateral condyle (r2 = 0.26, P = 0.011).

Conclusions

Race training inhibits remodelling in the subchondral bone of highly loaded areas of the distal metacarpus. Therefore periods of less intense loading are important for allowing repair of subchondral bone fatigue in Thoroughbred racehorses.

Ethical Animal Research

The study was performed on material collected during post‐mortem examination. Sources of funding: Rural Industries Research and Development Corporation of the Australian Commonwealth Government and Racing Victoria Limited. Competing interests: none.
Factors Affecting Owners' Choice of Nutritional Supplements in Dressage and Eventing Horses
Authors: Gemmill R , Agar C , Freeman S , Hollands T
Published: June 2014

Introduction

Horse owners are faced with a vast range of supplements and different sources of information. The aim of this study was to evaluate sources of information used by owners/riders when choosing supplements for competition horses, their opinions on different sources of information and evaluation of factors that affect their decisions.

Methods

A mixed methods (open and closed questions) online questionnaire was distributed through British Eventing and Dressage websites to owners/riders of dressage and/or event horses, to collect data on the demographics of the owner/rider and their horses, sources of information used when choosing nutritional supplements, and their opinion on these different sources. Data was evaluated using descriptive analysis and Chi‐squared tests for quantitative data, and thematic analysis for qualitative data.

Results

757 responses met the inclusion criteria, and owners/riders competed at dressage and eventing from unaffiliated novice to affiliated advanced level. Veterinary surgeons were considered the most reliable source of information, followed by nutritionists, research studies, coach/trainer and other horse owners. ‘Other horse owners’ were the top source (18% of participants) for the participants' most recent choice of supplement. Respondents with a higher education qualification were significantly more likely to use research papers as a source of information (P<0.005). Owners/riders under 34 years of age were significantly more likely to use a coach / trainer as a source of information (P<0.005).

Conclusions

Horse owners identified veterinary surgeons, nutritionists and research papers as reliable sources of information, but ultimately most chose their supplement based on recommendations of other owners or coaches/trainers.

Ethical Animal Research

The study was reviewed and approved by the School of Veterinary Medicine and Science Ethics Committee at the University of Nottingham. Sources of funding: School of Veterinary Medicine and Science at the University of Nottingham. Competing interests: Teresa Hollands is employed by Dodson and Horrell Ltd.
Energy Expenditure During a 160 km Endurance Race
Authors: Goachet A , Loriers A , Le Floch E , Julliand V
Published: June 2014

Introduction

In endurance racing, horses are required to complete distances of up to 160 km in a single day. To date, the energy expenditure (EE) of such effort has not been quantified. This study aimed to evaluate EE during a 160 km endurance race from heart rate (HR) monitoring.

Methods

Three weeks before competing, two endurance horses (H1 and H2) were submitted to a field exercise test to determine their individual VO2‐HR relationship. VO2 and HR were recorded simultaneously at trot (13–14 km/h for 10 min), and at canter (18–19 km/h for 10 min, and 22–23 km/h for 5 min), using the equine K4b2, a portable metabolic measurement system. H1 was then enrolled in Monpazier CEI and H2 in Florac CEI. HR was monitored from 2 minutes before the start to the finishing line of each loop. EE of exercise was calculated from individual VO2‐HR relationship and caloric equivalent of oxygen.

Results

H1 and H2 completed the race at an average speed of 17.02 and 14.46 km/h, respectively. Mean HR was 108 ± 8 and 124 ± 24 and peak HR was 169 and 204 for H1 and H2, respectively. The proportion of time spent at HR≥180 was 0 and 2.7% for H1 and H2 respectively. EE of exercise was evaluated at 177 and 240 MJ for H1 and H2 respectively.

Conclusions

A 160‐km endurance race might present a considerable energy cost, at least 5 times the EE of non‐working state.

Ethical Animal Research

The project was conducted under license from the Department of Health and Animal Care of the French Veterinary Authority (no. A21002) and ethics committee approval n° B0710. Sources of funding: Burgundy Region and AgroSup Dijon. Competing interests: none.
Novel biosensors based on optimized glycine oxidase
Authors: Rosini Elena , Piubelli Luciano , Molla Gianluca , Frattini Luca , Valentino Mattia , Varriale Antonio , D'Auria Sabato , Pollegioni Loredano
Published: June 2014

Glycine is involved in several physiological functions, e.g. as a neurotransmitter in the central nervous system, and sarcosine has been identified as a differential metabolite greatly enhanced during prostate cancer progression and metastasis. Glycine oxidase from Bacillus subtilis (GO) was engineered with the final aim of producing specific analytical systems to detect these small achiral amino acids. Based on in silico analysis, site‐saturation mutagenesis was independently performed at 11 positions: a total of 16 single‐point GO variants were analyzed. Significantly improved kinetic parameters were observed on glycine for the A54R, H244K‐N‐Q‐R, Y246W and M261R variants. The introduction of multiple mutations then identified the H244K/M261R variant showing a 5.4‐fold increase in maximal activity on glycine. With sarcosine as substrate, a number of single‐point variants showed increased maximal activity and/or affinity: the kinetic efficiency was increased 6‐fold for the M49L variant. Two GO variants with a high substrate specificity ratio for glycine (versus sarcosine, i.e. H244K GO) or for sarcosine (versus glycine, i.e. M49L GO) combined with high substrate affinity were used to set up a simple fluorescence‐based biosensor. This optical sensing assay represents a novel, inexpensive and fast tool to assay glycine or sarcosine concentrations in biological samples (detection limit ≤ 0.5 μm).
Enhancement of mitochondrial ATP production by the Escherichia coli cytotoxic necrotizing factor 1
Authors: Travaglione Sara , Loizzo Stefano , Rizza Teresa , Del Brocco Antonella , Ballan Giulia , Guidotti Marco , Vona Rosa , Di Nottia Michela , Torraco Alessandra , Carrozzo Rosalba , Fiorentini Carla , Fabbri Alessia
Published: June 2014

Mitochondria are dynamic organelles that constantly change shape and structure in response to different stimuli and metabolic demands of the cell. The Escherichia coli protein toxin cytotoxic necrotizing factor 1 (CNF1) has recently been reported to influence mitochondrial activity in a mouse model of Rett syndrome and to increase ATP content in the brain tissue of an Alzheimer's disease mouse model. In the present work, the ability of CNF1 to influence mitochondrial activity was investigated in IEC‐6 normal intestinal crypt cells. In these cells, the toxin was able to induce an increase in cellular ATP content, probably due to an increment of the mitochondrial electron transport chain. In addition, the CNF1‐induced Rho GTPase activity also caused changes in the mitochondrial architecture that mainly consisted in the formation of a complex network of elongated mitochondria. The involvement of the cAMP‐dependent protein kinase A signaling pathway was postulated. Our results demonstrate that CNF1 positively affects mitochondria by bursting their energetic function and modifying their morphology.
Do individually ventilated cage systems generate a problem for genetic mouse model research?
Authors: Logge W. , Kingham J. , Karl T.
Published: June 2014

Technological developments over recent decades have produced a novel housing system for laboratory mice, so‐called ‘individually ventilated cage’ (IVC) systems. IVCs present a cage environment which is different to conventional filter‐top cages (FILTER). Nothing is known about the consequences of IVC housing on genetic mouse models, despite studies reporting IVC‐mediated changes to the phenotypes of inbred mouse strains. Thus, in this study, we systematically compared the established behavioural phenotype of a validated mouse model for the schizophrenia risk gene neuregulin 1 (TM Nrg1 HET) kept in FILTER housing with Nrg1 mutant mice raised in IVC systems. We found that particular schizophrenia‐relevant endophenotypes of TM Nrg1 HETs which had been established and widely published using FILTER housing were altered when mice were raised in IVC housing. IVCs diminished the schizophrenia‐relevant prepulse inhibition deficit of Nrg1 mutant males. Furthermore, IVC housing had a sex‐dependent moderate effect on the locomotive phenotype of Nrg1 mice across test paradigms. Behavioural effects of IVC housing were less prominent in female mice. Thus, transferring the breeding colony of mouse mutants from FILTER to IVC systems can shift disease‐relevant behaviours and therefore challenge the face validity of these mice. Researchers facing an upgrade of their mouse breeding or holding facilities to IVC systems must be aware of the potential impact this upgrade might have on their genetic mouse models. Future publications should provide more details on the cage system used to allow appropriate data comparison across research sites.
The cascade of care in the Eastern European country of Georgia
Authors: Chkhartishvili N , Sharavdze L , Chokoshvili O , DeHovitz JA , del Rio C , Tsertsvadze T
Published: June 2014

Objectives

Individual and public health benefits of antiretroviral therapy (ART) rely on successful engagement of HIV‐infected patients in care. We aimed to evaluate the HIV care continuum in the Eastern European country of Georgia.

Methods

The analysis included all adult (age ≥ 18 years) HIV‐infected patients diagnosed in Georgia from January 1989 until June 2012. Data were extracted from the national HIV/AIDS database as of 1 October 2012. The following stages of the HIV care continuum were quantified: HIV infected, HIV diagnosed, linked to care, retained in care, eligible for ART and virologically suppressed.

Results

Of 3295 cumulative cases of adult HIV infection reported in Georgia, 2545 HIV‐infected patients were known to be alive as of 1 October 2012, which is 52% of the estimated 4900 persons living with HIV in the country. Of the 2545 persons diagnosed with HIV infection, 2135 (84%) were linked to care and 1847 (73%) were retained in care. Of 1446 patients eligible for ART, 1273 (88%) were on treatment and 985 (77%) of them had a viral load < 400 HIV‐1 RNA copies/mL. Overall, 39% of those diagnosed and 20% of those infected had a suppressed viral load.

Conclusions

The findings of our analysis demonstrate that the majority of patients diagnosed with HIV infection are retained in care. Loss of patients occurs at each step of the HIV care continuum, but the major gap is at the stage of HIV diagnosis. Reducing the number of persons living with undiagnosed HIV infection and simultaneously enhancing engagement in continuous care will be critical to achieve maximum individual and public health benefits of ART.
Two novel alleles HLA‐A*02:433 and HLA‐A*02:434 identified in Saudi bone marrow donors using sequence‐based typing
Authors: Fakhoury H. A. , Jawdat D. , Alaskar A. S. , Al Jumah M. , Cereb N. , Hajeer A. H.
Published: June 2014

In this report, we present two novel HLA‐A alleles: HLA‐A*02:433 and HLA‐A*02:434. These alleles were identified by sequence‐based typing method (SBT), in two donors for the Saudi Bone Marrow Donor Registry (SBMDR). Allele A*02:433 is identical to A*02:05:01G except for a G to A substitution at nucleotide position 449 in exon 2. This substitution results in glycine to serine substitution at position 83. Whereas, allele A*02:434 is identical to A*02:01:01G except for a C to A substitution at nucleotide position 245 in exon 2, which results in phenylalanine to threonine substitution at position 15. The generation of both alleles appears to be the result of nucleotide point mutation involving 02:01:01 and 02:05:01.
Independent and combined influence of neonatal and current body composition on academic performance in youth: The UP & DOWN Study
Authors: Esteban‐Cornejo I. , Tejero‐González C. M. , Castro‐Piñero J. , Conde‐Caveda J. , Cabanas‐Sanchez V. , Sallis J. F. , Veiga Óscar L. ,   UP & DOWN Study Group
Published: June 2014

Backgrounds

Unhealthy body composition is a cause for concern across the lifespan.

Objective

The objective of this study was to examine the independent and combined associations between neonatal and current body composition with academic performance among youth.

Methods

This cross‐sectional study was conducted with a total of 1557 youth (745 girls) aged 10.4 ± 3.4 years. Birth weight and length at birth were self‐reported. Current body composition was assessed by body mass index (BMI), waist circumference (WC) and percentage of body fat (BF%). Academic performance was assessed through schools records.

Results

Birth weight was related to all academic variables in boys, independent of potential confounders, including BMI; whereas WC, BMI and BF% were related to all academic performance indicators in both boys and girls, independent of potential confounders, including birth weight (all P < 0.05). In addition, the combined adverse effects of low birth weight and current overweight on academic performance were observed in both boys and girls for grade point average (GPA) indicator. Boys in the group with none adverse effect had significantly higher scores in GPA (score +0.535; 95% confidence interval, 0.082–0.989) than boys in the group of both adverse effects (P < 0.007); among girls, GPA score was higher in the group with none adverse effect than in the groups with one or two adverse effects (P for trend = 0.029).

Conclusions

Neonatal and current body composition, both independently and combined, may influence academic performance in youth.