Evason Michelle D, Carr Anthony P, Taylor Susan M, Waldner Cheryl L
Veterinary Teaching Hospital, Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, S7N 5B4, Canada.
Am J Vet Res. 2004 Mar;65(3):333-7. doi: 10.2460/ajvr.2004.65.333.
To determine effects of athletic conditioning on thyroid hormone concentrations in a population of healthy sled dogs.
19 healthy adult sled dogs.
Serum concentrations of thyroxine (T4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), free T4 (fT4), free T3 (fT3), and autoantibodies directed against T3, T4, and thyroglobulin were measured in sled dogs that were not in training (ie, nonracing season) and again after dogs had been training at maximum athletic potential for 4 months.
Analysis revealed significant decreases in T4 and fT4 concentrations and a significant increase in TSH concentration for dogs in the peak training state, compared with concentrations for dogs in the untrained state. Serum concentrations of T4 and fT4 were less than established reference ranges during the peak training state for 11 of 19 and 8 of 19 dogs, respectively; fT4 concentration was greater than the established reference range in 9 of 19 dogs in the untrained state.
Decreased total T4 and fT4 concentrations and increased serum concentrations of TSH were consistently measured during the peak training state in healthy sled dogs, compared with concentrations determined during the untrained state. Although thyroid hormone concentrations remained within the established reference ranges in many of the dogs, values that were outside the reference range in some dogs could potentially lead to an incorrect assessment of thyroid status. Endurance training has a profound impact on the thyroid hormone concentrations of competitive sled dogs.
确定运动训练对一群健康雪橇犬甲状腺激素浓度的影响。
19只健康成年雪橇犬。
在未进行训练的雪橇犬（即非比赛季节）中测量血清甲状腺素（T4）、三碘甲状腺原氨酸（T3）、促甲状腺激素（TSH）、游离T4（fT4）、游离T3（fT3）以及针对T3、T4和甲状腺球蛋白的自身抗体浓度，在犬只以最大运动潜能训练4个月后再次测量。
分析显示，与未训练状态的犬只相比，处于训练高峰期的犬只T4和fT4浓度显著降低，TSH浓度显著升高。在训练高峰期，19只犬中有11只的T4血清浓度和19只中有8只的fT4血清浓度低于既定参考范围；在未训练状态下，19只犬中有9只的fT4浓度高于既定参考范围。
与未训练状态下测定的浓度相比，健康雪橇犬在训练高峰期持续测得总T4和fT4浓度降低，血清TSH浓度升高。尽管许多犬只的甲状腺激素浓度仍在既定参考范围内，但部分犬只超出参考范围的值可能会导致对甲状腺状态的错误评估。耐力训练对竞技雪橇犬的甲状腺激素浓度有深远影响。
