Liphook Equine Hospital, Liphook, Hampshire GU30 7JG, UK.
Liphook Equine Hospital, Liphook, Hampshire GU30 7JG, UK.
Vet J. 2022 Aug;286:105857. doi: 10.1016/j.tvjl.2022.105857. Epub 2022 Jul 5.
Use of plasma adrenocorticotropic hormone (ACTH) concentrations for the diagnosis of PPID in equids requires awareness of other factors that might influence ACTH concentrations, including breed and time of year. This study was designed to investigate effects of breed on plasma ACTH concentrations and potential interactions between breed and time of year. Ten breeds were selected from a laboratory database containing data on plasma ACTH concentrations. Breeds represented were Arabians, Cobs, Connemara ponies, donkeys, Irish Sports horses, New Forest ponies, Shetland ponies, Thoroughbreds, Warmbloods and Welsh breeds. Multivariable analysis was used to determine the effects of month and breed on plasma ACTH concentrations. A circannual pattern of ACTH concentration was documented, with a nadir in April and a peak in September. Arabian horses and donkeys had significantly higher ACTH concentrations than some other breeds, primarily from May to November, whereas in Shetland ponies and Welsh breeds, relatively higher ACTH concentrations only occurred from July to November. The annual increase in plasma ACTH appeared to commence in late April/early May in response to increasing daylight and decreased again promptly after the late September equinox as daylength fell below 12 h per day. Inter-breed differences in plasma ACTH were substantial and indicated that breed and time of year should be considered when interpreting plasma ACTH concentrations in equids suspected for PPID.
使用血浆促肾上腺皮质激素（ACTH）浓度来诊断马属动物的 PPID 需要注意其他可能影响 ACTH 浓度的因素，包括品种和一年中的时间。本研究旨在调查品种对血浆 ACTH 浓度的影响，以及品种和一年中时间之间的潜在相互作用。从一个包含血浆 ACTH 浓度数据的实验室数据库中选择了 10 个品种。所选品种为阿拉伯马、考布马、康尼马拉小马、驴、爱尔兰运动马、新森林小马、设得兰小马、纯血马、温血马和威尔士马品种。多变量分析用于确定月份和品种对血浆 ACTH 浓度的影响。记录了 ACTH 浓度的年循环模式，4 月达到最低点，9 月达到最高点。阿拉伯马和驴的 ACTH 浓度明显高于其他一些品种，主要是从 5 月到 11 月，而在设得兰小马和威尔士马品种中，相对较高的 ACTH 浓度仅在 7 月到 11 月之间发生。血浆 ACTH 的年度增加似乎在 4 月底/5 月初开始，这是对日照增加的反应，而在 9 月下旬秋分之后，随着每天的日照时间低于 12 小时，血浆 ACTH 又迅速下降。品种间血浆 ACTH 的差异很大，这表明在解释疑似患有 PPID 的马属动物的血浆 ACTH 浓度时，应考虑品种和一年中的时间。
