Faculdade de Veterinária, Universidade Federal Fluminense, Niterói, Rio de Janeiro, 24230-340, Brazil.
Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Lasplaces 11 1550, Montevideo, 11600, Uruguay.
Theriogenology. 2021 Oct 1;173:32-36. doi: 10.1016/j.theriogenology.2021.06.019. Epub 2021 Jun 30.
The present study aims to evaluate the effect of administering prostaglandin (250 μg cloprostenol) and oxytocin (10 UI) or a GnRH agonist (4.2 μg buserelin acetate) on rams' physiological responses to electroejaculation and the ejaculate's characteristics. The study was performed with a 2 × 2 factorial arrangement, according to whether it used oxytocin and prostaglandin (OXPGF) or GnRH. Therefore, there were four treatments: GControl = saline; GOXPGF = administration of PGF2α and oxytocin; GGnRH = administration of GnRH; administration of GOXPGF + GnRH = GnRH and PGF2α + oxytocin. An interaction between the hormonal treatments in the heart rate occurred: while the heart rate decreased when using OXPGF alone (control: 113.7 bpm vs. GOXPGF: 103.5 bpm, pooled SEM; P = 0.02), it did not modify when applying both treatments simultaneously and administering GnRH (GGnRH: 109.1 bpm vs. GOXPGF + GnRH: 111.5 bpm respectively, pooled SEM = 4.5). The respiratory rate also decreased with the administration of OXPGF (38.7 vs. 46.3 with and without OXPGF, pooled SEM = 10.0, P = 0.003). Administering OXPGF also tended to decrease the temperature (38.77 °C vs. 38.94 °C, with and without OXPGF, respectively, pooled SEM = 0.06; P = 0.056). Blood glucose increased with the administration of OXPGF from 58.7 mg/dL to 62.4 mg/dL (pooled SEM = 1.3, P = 0.014) and varied with time. CK concentrations increased from 641.8 mg/dL to 881.7 mg/dL (pooled SEM = 50.6) with the administration of OXPGF. GnRH administration decreased cortisol concentration from 7.3 ng/mL to 2.1 ng/mL (pooled SEM = 1.4; P = 0.04). The treatments had no effects on the time required for EE, the pulse at which the animals began and ended the ejaculation, or the vocalizations emitted during EE. There were no effects in any evaluated sperm variable. The research concluded that the administration of oxytocin and analogs of PGF2alpha decreased the stress response to electroejaculation, as well as administering GnRH agonist was slightly effective as it only decreased cortisol concentration. Also, these treatments, either alone or combined, did not affect the characteristics of the ejaculate collected.
本研究旨在评估给予前列腺素（250μg氯前列醇）和催产素（10UI）或 GnRH 激动剂（4.2μg布舍瑞林乙酸盐）对公羊电刺激采精生理反应和精液特征的影响。该研究采用 2×2 析因设计，根据是否使用催产素和前列腺素（OXPGF）或 GnRH。因此，有四种处理方法：GControl = 生理盐水；GOXPGF = PGF2α 和催产素给药；GGnRH = GnRH 给药；GOXPGF+GnRH 给药 = GnRH 和 PGF2α+催产素给药。激素处理对心率有交互作用：单独使用 OXPGF 时心率降低（对照：113.7 bpm 与 GOXPGF：103.5 bpm，合并 SEM；P=0.02），同时使用两种药物和 GnRH 时则没有改变（GGnRH：109.1 bpm 与 GOXPGF+GnRH：111.5 bpm，合并 SEM=4.5）。呼吸频率也随着 OXPGF 的给药而降低（38.7 与 46.3，有和没有 OXPGF，合并 SEM=10.0，P=0.003）。给予 OXPGF 也倾向于降低体温（38.77°C 与 38.94°C，有和没有 OXPGF，合并 SEM=0.06；P=0.056）。血糖随着 OXPGF 的给药从 58.7mg/dL 增加到 62.4mg/dL（合并 SEM=1.3，P=0.014）并随时间变化。CK 浓度随着 OXPGF 的给药从 641.8mg/dL 增加到 881.7mg/dL（合并 SEM=50.6）。给予 GnRH 可使皮质醇浓度从 7.3ng/mL 降低到 2.1ng/mL（合并 SEM=1.4；P=0.04）。这些处理方法对 EE 所需的时间、动物开始和结束射精的脉搏或 EE 期间发出的发声没有影响。在任何评估的精子变量中都没有影响。研究得出结论，给予催产素和 PGF2alpha 类似物可降低电刺激采精的应激反应，而给予 GnRH 激动剂则略有效果，因为它仅降低了皮质醇浓度。此外，这些处理方法，无论是单独使用还是联合使用，都不会影响采集到的精液特征。
