Northern Farm Tenei, Fukushima, Japan.
United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.
J Vet Intern Med. 2021 Jul;35(4):2002-2008. doi: 10.1111/jvim.16145. Epub 2021 May 24.
Pituitary pars intermedia dysfunction (PPID) is an endocrine disorder the clinical signs of which include infertility, but few reports have examined the relationship between PPID and reproductive performance in broodmares.
HYPOTHESIS/OBJECTIVE: Broodmares with infertility of unknown etiology were screened for PPID using baseline endogenous plasma ACTH concentrations, and its relationship with subsequent reproductive performance was analyzed.
Sixty-seven Thoroughbred broodmares.
Adrenocorticotropic hormone concentrations were measured in autumn. The broodmares were divided into 3 groups based on endogenous plasma ACTH concentration (low, <50 pg/mL; intermediate 50-100 pg/mL; and high >100 pg/mL) as recommended by the Equine Endocrinology Group. We compared these results with those of other blood tests, clinical examinations, subsequent conception, and frequency of normal delivery.
The numbers of horses per group (percentage) were 22 (32.8%), 20 (29.9%), and 25 (37.3%). The mean ± SD ages (years) were 11.1 ± 3.4, 12.1 ± 4.5, and 13.0 ± 4.3, with no significant difference among groups. Mean ± SD plasma cortisol concentrations (μg/dL) were 4.0 ± 1.6, 7.1 ± 1.4, and 7.6 ± 1.9, with the intermediate and high ACTH groups having significantly higher results than the low ACTH group (P < .001). Conception rates were 77.3%, 89.5%, and 56.5% and normal delivery rates were 77.2%, 84.2%, and 43.5% with the percentage of each significantly lower in the high ACTH group (P = .02, P = .008, respectively).
The study group of infertile broodmares may include horses with PPID. The reproductive performance of the high ACTH group was significantly lower than the other groups. Early diagnosis and treatment of infertile broodmares by screening plasma ACTH concentrations could help improve reproductive performance.
垂体中间叶功能减退症（PPID）是一种内分泌紊乱，其临床症状包括不孕，但很少有报道研究 PPID 与种马的繁殖性能之间的关系。
假设/目的：使用基础内源性血浆 ACTH 浓度筛选不明原因不孕的种马是否患有 PPID，并分析其与随后繁殖性能的关系。
67 匹纯种母马。
在秋季测量促肾上腺皮质激素（ACTH）浓度。根据内源性血浆 ACTH 浓度（低，<50pg/mL；中 50-100pg/mL；高 >100pg/mL）将种马分为 3 组，这是根据马属动物内分泌学组的建议进行的。我们将这些结果与其他血液检查、临床检查、随后的受孕情况和正常分娩频率进行了比较。
每组的马匹数量（百分比）分别为 22（32.8%）、20（29.9%）和 25（37.3%）。平均年龄（岁）±标准差分别为 11.1±3.4、12.1±4.5 和 13.0±4.3，组间无显著差异。平均血浆皮质醇浓度（μg/dL）±标准差分别为 4.0±1.6、7.1±1.4 和 7.6±1.9，中、高 ACTH 组显著高于低 ACTH 组（P<.001）。受孕率分别为 77.3%、89.5%和 56.5%，正常分娩率分别为 77.2%、84.2%和 43.5%，高 ACTH 组的百分比显著较低（P=.02，P=.008）。
不孕的种马研究组可能包括患有 PPID 的马。高 ACTH 组的繁殖性能明显低于其他组。通过筛选血浆 ACTH 浓度对不孕种马进行早期诊断和治疗，可能有助于提高繁殖性能。
