Jacquay Erica T, Harris Patricia A, Adams Amanda A
M. H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, Kentucky, USA.
Equine Studies Group, Waltham Petcare Science Institute, Waltham on the Wolds, Leicestershire, UK.
Equine Vet J. 2025 May;57(3):745-755. doi: 10.1111/evj.14403. Epub 2024 Sep 4.
It is unknown whether short-term transportation affects endocrine responses similarly in horses with and without insulin dysregulation (ID).
To characterise the effect of short-term transportation on stress parameters and insulin responses to an oral sugar test (OST) in horses with and without ID.
Longitudinal cohort study.
Fourteen adult non-pregnant, non-PPID mares of mixed light breeds were grouped as either ID (n = 7) or non-ID (n = 7) based on endocrine testing. Over 2 weeks, horses were transported once, in groups of 3-4 in a horse trailer on a round-trip journey of ~1.5 h. Blood and saliva were collected 24 h and 1 h pre-transportation, directly after unloading and 15 min, 1 h, 3 h plus 24 h post-transportation. An OST was performed 24 h pre-transportation and 3 h post-transportation with a pre- (T0) and post-OST sample collected 60 min later (T60). Heart rates and rectal temperatures were also collected throughout the study. Serum insulin, serum cortisol, and plasma glucose were measured using validated assays. Repeated measures ANOVA were used to determine differences after transportation and between ID and non-ID horses. Non-normal data were log-transformed and multiple comparisons were adjusted using Bonferroni post hoc tests.
Mean insulin was higher in ID horses versus non-ID horses (mean = 109.9 μU/mL vs. 30.2 μU/mL, p < 0.001; 95% CI for mean difference = [55.6-107.7 μU/mL]). Mean serum insulin increased following OST at T60 in ID horses pre- (154.6 μU/mL, p = 0.04; 95% CI = [86.3-223.0 μU/mL]) and post-transportation (284.6 μU/mL, p = 0.03; 95% CI = [114.3-454.8 μU/mL]). Non-ID horses had a mean OST T60 insulin post-transportation of 56.6 μU/mL (95% CI = [29.1-84.1 μU/mL]); above recognised threshold [45 μU/mL] for ID diagnosis.
Small number of horses, only mares used, and OST not performed immediately post-transportation.
Performing an OST 3 h following short-term transportation may result in inaccurate ID status.
短期运输对胰岛素调节异常（ID）的马匹和未患该病的马匹内分泌反应的影响是否相似尚不清楚。
描述短期运输对ID马匹和未患该病的马匹应激参数以及口服糖耐量试验（OST）胰岛素反应的影响。
纵向队列研究。
14匹成年非妊娠、非垂体中间叶功能减退（PPID）的混合轻品种母马，根据内分泌检测分为ID组（n = 7）和非ID组（n = 7）。在2周内，马匹被分组（每组3 - 4匹）用运马拖车运输一次，往返行程约1.5小时。在运输前24小时和1小时、卸载后即刻以及运输后15分钟、1小时、3小时和24小时采集血液和唾液样本。在运输前24小时和运输后3小时进行OST，在OST前（T0）和60分钟后（T60）采集样本。在整个研究过程中还收集心率和直肠温度。使用经过验证的检测方法测量血清胰岛素、血清皮质醇和血浆葡萄糖。采用重复测量方差分析来确定运输后以及ID和非ID马匹之间的差异。对非正态数据进行对数转换，并使用Bonferroni事后检验对多重比较进行校正。
ID组马匹的平均胰岛素水平高于非ID组马匹（平均值分别为109.9 μU/mL和30.2 μU/mL，p < 0.001；平均差异的95%置信区间 = [55.6 - 107.7 μU/mL]）。ID组马匹运输前T60时OST后平均血清胰岛素升高（154.6 μU/mL，p = 0.04；95%置信区间 = [86.3 - 223.0 μU/mL]），运输后升高（284.6 μU/mL，p = 0.03；95%置信区间 = [114.3 - 454.8 μU/mL]）。非ID组马匹运输后OST T60时的平均胰岛素水平为56.6 μU/mL（95%置信区间 = [29.1 - 84.1 μU/mL]）；高于ID诊断公认阈值[45 μU/mL]。
马匹数量少，仅使用母马，且运输后未立即进行OST。
短期运输后3小时进行OST可能导致ID状态诊断不准确。
