The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform

Livia Olsen - One of the best experts on this subject based on the ideXlab platform.

Catherine W Kohn - One of the best experts on this subject based on the ideXlab platform.

  • contributions of Equine Exercise physiology research to the success of the 1996 equestrian olympic games a review
    Equine Veterinary Journal, 2010
    Co-Authors: L B Jeffcott, Catherine W Kohn
    Abstract:

    Summary Following public concern about the weather conditions for the 1996 Olympic Games in Atlanta an international research programme was initiated. The primary objective of this effort was to identify strategies for ensuring welfare of horses competing in the heat. Field observations of horses during the endurance test of 3-day events in Europe, Canada, and the USA characterised the work effort of this form of competition; laboratory treadmill studies assessed limitations to performance of heat and humidity, explored the relationships of thermoregulatory demands to the phases of the competition and documented fluid and electrolyte losses. Estimates of energy expenditure and heat production during the endurance test were made. Strategies for facilitating heat dissipation were also studied in depth. Assessment of the effect of environmental conditions was based upon intensive climate monitoring using a modification of the Wet Bulb Globe Temperature index. Studies of heat acclimation provided a basis for recommendation of acclimatisation times for horses before the Games. The results of all these studies guided the management of Equine athletes at the 1996 Olympic Games and significantly advanced knowledge of thermoregulation in competitive horses.

R H Sides - One of the best experts on this subject based on the ideXlab platform.

  • Effect of different protocols on the mitigation of Exercise‐induced pulmonary hemorrhage in horses when administered 24 hours before strenuous Exercise
    Journal of Veterinary Internal Medicine, 2019
    Co-Authors: Warwick M. Bayly, R H Sides, Carolina Lopez, Gerald Bergsma, Jenyka Bergsma, Jenifer R. Gold, Debra C. Sellon
    Abstract:

    BACKGROUND: Public pressure exists in the United States to eliminate race-day furosemide administration despite its efficacy in decreasing the severity of Equine Exercise pulmonary hemorrhage (EIPH). No effective alternative prophylaxis strategies have been identified. OBJECTIVE: To investigate alternative protocols to race-day furosemide that might mitigate EIPH. ANIMALS: Seven fit Thoroughbreds with recent EIPH. METHODS: Double-blinded placebo-controlled Latin square crossover using a treadmill followed by a blinded placebo-controlled crossover study at a racetrack. First, horses Exercised supramaximally to fatigue 24 hours after initiating 5 EIPH prophylaxis protocols: 0.5 and 1.0 mg/kg furosemide IV 24 hours pre-Exercise with and without controlled access to water, and 24 hour controlled access to water. Effects were compared to those measured after giving a placebo 24 hours pre-Exercise, and 0.5 mg/kg furosemide IV 4 hours pre-Exercise. Bronchoalveolar lavage (BAL) erythrocyte count was determined 45-60 minutes postExercise after endoscopy to assign an EIPH score. Data were analyzed using linear mixed effects models. The most promising protocol from the treadmill study was further evaluated in 6 horses using endoscopy and BAL after 1100 m simulated races. RESULTS: Intravenous furosemide (0.5 mg/kg) administered 24 hours pre-Exercise combined with controlled access to water decreased the severity of EIPH on the treadmill and at the racetrack. CONCLUSION AND CLINICAL IMPORTANCE: Administering 0.5 mg/kg furosemide 24 hours pre-racing combined with controlling water intake may be a strategy to replace race-day furosemide administration for the management of EIPH. A larger study is indicated to further evaluate whether this protocol significantly mitigates EIPH severity.

  • Changes in arterial, mixed venous and intraerythrocytic ion concentrations during prolonged Exercise
    Equine Veterinary Journal, 2010
    Co-Authors: N. D. Meyer, R H Sides, Warwick M. Bayly, K. J. Wardrop, B. K. Slinker
    Abstract:

    Summary Reasons for performing study: Prolonged Equine Exercise can cause hypochloraemic alkalosis and hypokalaemia secondary to the loss of hypertonic sweat. Movement of ions in and out of erythrocytes during Exercise may help regulate acid-base balance and changes in plasma ion concentrations. The extent to which this happens during prolonged Equine Exercise has not been reported. Objectives: To measure changes in blood gases and major plasma and intraerythrocytic (iRBC) ion concentrations of horses undergoing prolonged submaximal Exercise. Methods: Six horses were trotted at ∼30% VO2max on a treadmill for 105 min. Arterial (a) and mixed venous (v) blood samples were collected every 15 min, and pre- and post Exercise. Blood gases and plasma (pl) concentrations of sodium, potassium, chloride and protein were measured and their iRBC concentrations calculated and compared (P

  • effect of breathing frequency and airflow on pulmonary function in high intensity Equine Exercise
    Equine Veterinary Journal, 2010
    Co-Authors: W M Bayly, M J Redman, R H Sides
    Abstract:

    Summary It has been postulated that the hypoxaemia and hypercapnoea that characterise strenuous Equine Exercise are partly due to flow limitations imposed by high breathing frequencies (fb), and that gas exchange would be improved if fb could be lowered. To evaluate this possibility, 6 Thoroughbred horses underwent 4 incremental treadmill Exercise tests at inclines of 0,5,10 and 25%, respectively. In the test, horses were given a warm-up for 2 min, then ran sequentially for 1 min each at 60, 100 and 115% Vo2max. Oxygen consumption (Vo2), blood gas tensions (Pao2, Paco2), fb, tidal volume (VT), minute ventilation (Ve), transpulmonary pressure (Ptp), peak inspiratory and expiratory airflows (VI VE) and work of breathing (Ẇrm) were determined during the last 15 s of Exercise at each intensity. The only effect of fb on Pao2 was seen at 60% Vo2max. Also, maximal transpulmonary pressure difference (ΔPtpmax), and peak VI, and VE on a 25% slope were lower than those recorded at the other 3 inclines at 60% Vo2max. At 100 and 115% Vo2max, the effect of fb was less clear. While fb still differed, the only effects of fb at 100% Vo2max were on ΔPtpmax. At 115% Vo2max, fb on a 25% incline was lower than that for 0 and 5% slopes. The only other difference noted at this intensity was in VT on 10% slope. However, there was no difference between VTs recorded at inclines of 0,5 or 25% at 115% Vo2max. There was no effect of fb or Exercise intensity on Ve at 100 or 115% Vo2max. There was no change in Pao2, fb, VT, ΔPtpmax or VI and VE as Exercise intensity increased from 60–115% Vo2max on slopes of 0,5 or 10%. However, for Exercise on the 25% incline (i.e. with lower fb), each of these parameters increased (or decreased for Pao2) from 60–100%, but not from 100–115% Vo2max. Failure of peak airflow and VT to increase when intensity increased was associated with the development of hypoxaemia and hypercapnoea, regardless of slope or fb. It is concluded that while a low fb may have some beneficial effect on gas exchange during submaximal Exercise at ˜60% Vo2max, this effect disappears as Exercise intensity increases. There appear to be limits to the peak airflows that can be generated by horses during strenuous Exercise, and these limits may be reached regardless of fb. Flow limitation per se may play a greater role in the development of Exercise-induced hypoxaemia and hypercapnoea in horses than does fb.

J Pringle - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of Exercise variables measured during intensity of simulated training to variables at maximal effort in Standardbreds
    Equine Veterinary Journal, 1999
    Co-Authors: J Pringle, K. Macmillan, H. Briand, H Stampfli
    Abstract:

    The heart rate changes during routine training in a group of 8 actively racing Standardbreds were used to simulate the training work on a treadmill (ST) and indices of Exercise compared to maximal effort (MAX) on the treadmill. The following parameters were recorded during treadmill work: heart rate, velocity, O2 consumption, respiratory and stride frequency, and stride length. Blood lactate concentrations were measured before and after each work test. Heart rate during simulated training was mean±s.d. 87.8±5.5% heart rate in MAX, one of the 8 horses working 0.05), being higher during the ST. Most horses worked at intensities based on heart rate consistent with proposed guidelines of 80-90% of maximal heart rate. However, in 3 of the 8 horses work intensity of insufficient or excessive amounts may have occurred.ID: 7094; Accession Number: 20013049947. Publication Type: Journal Article; Conference paper. Note: Equine Exercise Physiology 5 Language: English. Number of References: 19 ref. Registry Number: 50-21-5. Subject Subsets: Veterinary Science; Veterinary Scienc

  • simple airflow direction and footfall sensors for use in Equine Exercise studies
    Equine Veterinary Journal, 1995
    Co-Authors: S Young, R J Geor, H Stampfli, L J Mccutcheon, J Pringle
    Abstract:

    Summary Two durable, inexpensive and non-invasive sensors for detecting airflow direction and footfall in exercising horses were developed. The airflow sensor measured temperature of the gas at the nostrils using a copper/constantan thermocouple. The response time of the thermocouple unit, the time for the signal to change from 10% to 90% of its final value, was 260 ms in forced air. The tip of the thermocouple was held just inside the false nostril by a small wire frame. The sensor did not interfere with placement of face masks and the addition of the mounting frame slightly decreased response time of the sensor to 208 ms. The footfall sensor was a simple accelerometer, using the contact arm of an electrical relay as a spring/mass unit. Bending of the metal strip was recorded using a strain gauge. The response of the accelerometer was highly under-damped when attached to a rigid surface (resonant frequency 117 Hz, quality factor (Q) 171) but attaching it to the hoof with adhesive foam increased the damping considerably. Both sensors were used in a study of Standardbred horses exercising maximally on a treadmill. Air temperature at the nostril changed from ambient on inspiration to about 35°C on expiration and each leading hoof strike produced a burst of signal from the accelerometer. The sensors may be useful in studies that examine respiration, stride rate and respiratory-locomotor coupling in exercising horses.

Shigeru Sugano - One of the best experts on this subject based on the ideXlab platform.

  • Studies on the Exercise physiology of draft horses performed in Japan during the 1950s and 1960s.
    Journal of Equine Science, 2017
    Co-Authors: Atsushi Hiraga, Shigeru Sugano
    Abstract:

    Although the total number of horses raised in Japan dramatically decreased after World War II, because draft horses were still used for farm work in paddy fields and on farms during the period of the 1950s and 1960s, a performance test for selecting better draft horses was needed. In order to determine the most suitable size of draft horses for Japanese farm conditions, the working power of horses weighing from 185 to 622 kg was evaluated by performing an endurance test, several kinds of working power tests, and maximum pulling power tests. Oxygen consumption during draft Exercise was measured by the Douglas bag method in order to evaluate effects of draft workload under the conditions of different types of work (14- and 18-cm plow depths, cultivator, and tillage), traction methods (shoulder traction, shoulder-trunk traction, and chest-trunk traction), walking speeds (40, 60, 80, 100, and 120 m/min), and depths of water (0, 18, 36, and 54 cm) on energy expenditure. The relationship between energy consumption and pulse rate during Exercise was also evaluated. A study of a performance test for draft horses was conducted to establish a new approach for evaluating draft horse performance using heart rate as an index. For this study, a beat meter for measuring heart rate was developed, and experimental protocols were used to evaluate the relationship between heart rate and workload. Although the research results obtained from these studies do not have particular relevance in the current day, these studies are valuable for understanding the history of Equine Exercise physiology in Japan.

  • Studies on Exercise physiology and performance testing of racehorses performed in Japan during the 1930s using recovery rate as an index.
    Journal of Equine Science, 2016
    Co-Authors: Atsushi Hiraga, Shigeru Sugano
    Abstract:

    The history of research on the Exercise physiology of racehorses in Japan dates back to the 1930s. A research report entitled "Studies on Exercise physiology and performance testing of the racehorse", published in 1933 by Shigeo Matsuba and Torao Shimamura of The University of Tokyo, was epoch-making and the most important study in the history of Equine Exercise physiology in Japan. Research results were reported from 92 Thoroughbred racehorses in a large-scale project during the period of 1928 to 1932 at the Shimofusa Imperial Farm and the Koiwai Farm, which were the two greatest racehorse farms at that time. A total of 20 physiological variables were measured to evaluate the fitness of Thoroughbred racehorses before Exercise (Pre), just after Exercise (Post), 1 hr after Exercise (1 hr), 2 hr after Exercise (2 hr), and 3 hr after Exercise (3 hr) in order to calculate their recovery rates as an index of fitness and performance. The percentage of the Pre value at 1 hr, 2 hr, and 3 hr was calculated. When the percentage of a variable reached 95-105% of the Pre value, the variable was considered to be recovered. The percentage of the total number of variables that were recovered for each time period was calculated, and an overall average was calculated from them; Matsuba and Shimamura proposed calling this overall average the "recovery rate", which could then be applied to evaluate each horse. The effects of training on racehorses were subsequently evaluated by measuring the various physiological variables and the recovery rate.

  • Studies on Exercise physiology of the racehorse performed in Japan during the period from the 1930s to the 1970s: respiration and heart rate during Exercise and the effect of Exercise on blood characteristics.
    Journal of Equine Science, 2016
    Co-Authors: Atsushi Hiraga, Shigeru Sugano
    Abstract:

    After publication of the epic report on Equine Exercise physiology by Matsuba and Shimamura in 1933, papers on Exercise physiology of the racehorse in Japan began appearing in scientific journals and increased in number. In 1944, respiration during Exercise at a walk, trot, and canter was measured by recording expiratory sounds with a microphone attached near the nostril. Respiratory frequency during cantering was synchronized with stride frequency, and expiratory sounds were found to occur during the stance phase of the trailing forelimb. Development of a radiotelemetry system in 1964 for electrocardiogram recording enabled the first recording of an Equine electrocardiogram during field Exercise that included fast galloping and calculation of heart rate (HR) during Exercise. During low intensity Exercise including walking, trotting, cantering and extended cantering, HR increased from 45 beat/min during pre-Exercise to 150 beat/min at an extended canter. HR increased to 200 beat/min or more in most horses during 100 m of high-intensity sprint galloping. When blood lactate was measured after 3 days of draft work in 12 warhorses in 1934, no increase in blood lactate was found. The erythrocyte sedimentation rate (ESR) was decreased by intense Exercise and also decreased as training increased. It was suggested that measuring changes in ESR and body weight in relation to training might become useful as a screening index of training, condition, and fatigue. This evaluation method was named the “ESR-body weight method.”