Perez R, Recabarren S E, Valdes P, Hetz E
Faculty of Veterinary Medicine, University of Concepcion-Chillan, Chile.
Vet Res Commun. 1992;16(3):231-46. doi: 10.1007/BF01839160.
A study was undertaken in five draught horses of 648 +/- 33 kg body weight to find the effects of continuously pulling loads on their cardiovascular, respiratory and metabolic responses. A cart equipped with an odometer, for measuring distance, and a hydraulic dynamometer, for measuring draught force, was used. Heart and respiration rates and rectal temperatures were recorded. Blood samples for measuring arterial and venous pH and blood gases, haemoglobin, glucose and lactic acid concentrations and the serum activity of the enzymes creatine phosphokinase (CK), lactate dehydrogenase, aspartate aminotransferase and alkaline phosphatase were taken before exercise and immediately after each journey (morning and afternoon) of the daily work. Draught exercise, with loads which generated forces of between 0.57 and 0.59 kN, at speeds of 1.60 to 2.11 m/s, for 8 h daily for five consecutive days, with resting intervals of 10 min each hour, was well tolerated. Exercise tolerance was evaluated from the recovery from the changes observed in the biochemical and physiological parameters induced by the work. The analysis of these showed that, when the horses were subjected to prolonged periods of resting, their loss of fitness for work was shown by significant increases in the serum activity of muscle-derived enzymes and in blood lactate concentrations during the first day of work. However, over the following days the horses adapted to the work, so that the decreases in serum enzyme activities and blood lactate concentrations were reduced. Since similar observations have been described for racehorses, the determination of blood lactate concentrations and the serum activities of muscle-derived enzymes, specifically CK, seem to be good indicators of fitness in draught horses.
对5匹体重为648±33千克的挽马进行了一项研究，以探究持续拉载负荷对其心血管、呼吸和代谢反应的影响。使用了一辆配备里程表（用于测量距离）和液压测力计（用于测量拉力）的马车。记录了心率、呼吸频率和直肠温度。在运动前以及每天工作的每个行程（上午和下午）结束后立即采集血样，用于测量动脉和静脉血的pH值、血气、血红蛋白、葡萄糖和乳酸浓度，以及肌酸磷酸激酶（CK）、乳酸脱氢酶、天冬氨酸转氨酶和碱性磷酸酶的血清活性。挽马每天以1.60至2.11米/秒的速度拉载负荷，负荷产生的力在0.57至0.59千牛之间，持续8小时，连续进行5天，每小时休息10分钟，结果显示马匹耐受性良好。根据工作引起的生化和生理参数变化的恢复情况评估运动耐受性。对这些参数的分析表明，当马匹长时间休息后，在工作的第一天，肌肉来源酶的血清活性和血乳酸浓度显著增加，表明它们的工作适应性下降。然而，在接下来的几天里，马匹适应了工作，血清酶活性和血乳酸浓度的下降幅度减小。由于对赛马也有类似的观察结果，因此测定血乳酸浓度和肌肉来源酶（特别是CK）的血清活性似乎是挽马适应性的良好指标。
