The objectives of this study were (1) to assess the effect of purulent vaginal discharge (PVD) on reproductive performance using a 4-point vaginal discharge score (VDS) and (2) to evaluate the effect of PGF_2α treatment in cows with PVD on reproductive performance. Holstein cows (n = 2,473) from 1 commercial dairy farm had their vaginal discharge scored at 32 ± 3 d in milk (DIM) using a 4-point scale. Cows were also scored for body condition score and had their ovaries examined using transrectal ultrasound. A VDS-2 or greater was used to define PVD. Cows with PVD were assigned to receive 2 doses of 500 µg of PGF_2α analogue (n = 277; Cloprostenol; PGF Veyx forte, Veyx Pharma Ltd., Schwarzenborn, Germany) 14 d apart (odd ear tag number) or remained untreated (n = 272; even ear tag number). All cows not detected in estrus at 90 ± 3 DIM were enrolled into a timed artificial insemination (AI) protocol. The effect of VDS and the effect of PGF_2α in cows with PVD on reproductive performance were evaluated separately. First service conception risk (FSCR), time to first AI, and time to pregnancy were used as indicators for reproductive performance. Data were analyzed with Cox's regression and mixed logistic models. The prevalence of PVD was 22.2% (548/2,473). We detected an interaction of parity and VDS for FSCR and time to pregnancy. In primiparous cows, VDS had no effect on FSCR and time to pregnancy. In multiparous cows, VDS had an effect on FSCR and time to pregnancy. Multiparous cows having a VDS-2 or a VDS-3 had decreased odds of pregnancy at first AI compared with cows having a VDS-0. Multiparous cows with VDS-1 or VDS-3 had a decreased hazard of conceiving within 200 DIM. The treatment effect of PGF_2α was conditional on parity. In primiparous animals with PVD without a corpus luteum present at 32 DIM, treatment with PGF_2α reduced FSCR. Irrespective of the presence of a corpus luteum, treatment with PGF_2α decreased the hazard of conceiving within 200 DIM in primiparous cows. Although multiparous cows with PVD treated with PGF_2α had increased odds of pregnancy at first AI, no treatment effect was observed on the hazard of conceiving within 200 DIM. Our results do not support the blanket use of PGF_2α as a treatment option in postpartum dairy cows having PVD.

本研究的目的是 (1) 使用 4 点阴道分泌物评分 (VDS) 评估脓性阴道分泌物 (PVD) 对繁殖性能的影响，以及 (2) 评估 PGF 2α 治疗对患有 PVD ​​的奶牛_的效果关于生殖性能。来自 1 个商业奶牛场的荷斯坦奶牛 (n = 2,473) 在牛奶中 32 ± 3 天 (DIM) 时使用 4 分制对其阴道分泌物进行评分。还对奶牛的身体状况进行评分，并使用经直肠超声检查其卵巢。VDS-2 或更高用于定义 PVD。患有 PVD ​​的奶牛被分配接受 2 剂 500 µg PGF _2α类似物（n = 277；氯前列醇；PGF Veyx forte，Veyx Pharma Ltd.，Schwarzenborn，德国），间隔 14 天（奇数耳标编号）或保持不治疗（n = 272；偶数耳标号）。所有未在 90 ± 3 DIM 发情时检测到的奶牛都被纳入定时人工授精 (AI) 方案。_{分别评估了 VDS 和 PGF 2α}对 PVD ​​奶牛繁殖性能的影响。首次受孕风险（FSCR）、首次 AI 时间和怀孕时间被用作生殖性能指标。使用 Cox 回归和混合逻辑模型分析数据。PVD 的患病率为 22.2% (548/2,473)。我们检测到胎次和 VDS 对 FSCR 和怀孕时间的相互作用。对于初产奶牛，VDS 对 FSCR 和妊娠时间没有影响。在经产奶牛中，VDS 对 FSCR 和妊娠时间有影响。与具有 VDS-0 的奶牛相比，具有 VDS-2 或 VDS-3 的多产奶牛首次人工授精时怀孕的几率较低。使用 VDS-1 或 VDS-3 的多产奶牛在 200 DIM 内受孕的风险降低。_{PGF 2α}的治疗效果以胎次为条件。在 32 DIM 时没有黄体的 PVD ​​初产动物中，使用 PGF _2α治疗可降低 FSCR。无论是否存在黄体，PGF _2α治疗都能降低初产奶牛 200 DIM 内受孕的风险。_{尽管经 PGF 2α}治疗的患有 PVD ​​的多产奶牛在第一次 AI 时怀孕的几率有所增加，但没有观察到治疗对 200 DIM 内受孕的风险有影响。我们的结果不支持全面使用 PGF _2α作为患有 PVD ​​的产后奶牛的治疗选择。