Pagliosa Ronaldo C, Derossi Rafael, Costa Deiler S, Faria Fabio J C
Department of Animal Reproduction, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Brazil.
J Vet Med Sci. 2015 Nov;77(11):1339-45. doi: 10.1292/jvms.14-0369. Epub 2015 Jun 22.
To test the hypothesis that epidural administration of lidocaine, xylazine or xylazine plus hyaluronidase provides reduced pain and stress during electroejaculation in bulls, eight 30-month-old Nellore bulls received saline solution (control), 2% lidocaine, 2% xylazine or 2% xylazine plus hyaluronidase injected into the first intercoccygeal (Co1-Co2) epidural space in randomized order. Heart rate, respiratory rate, mean arterial pressure, analgesia, animal behavior and motor blockade were evaluated before treatment and at predetermined intervals during and after treatment. Pain and stress were scored subjectively, and semen quality was evaluated. The onset of anesthetic action was significantly faster with lidocaine (3.0 ± 1.2 min) than with xylazine or xylazine plus hyaluronidase (8.9 ± 1.5 and 5.5 ± 2.6 min, P=0.021 and P=0.012, respectively), and the onset of anesthesia with xylazine plus hyaluronidase was significantly faster than that with xylazine alone (P=0.032). Treatment with xylazine or xylazine plus hyaluronidase resulted in less discomfort than treatment with lidocaine, as indicated by animal behavior. Changes in heart rate, respiratory rate and arterial pressure were within acceptable limits. Penile protrusion and semen emission occurred in all animals during all four treatments. Our results suggest that xylazine plus hyaluronidase reduced discomfort during electroejaculation more effectively than xylazine or lidocaine alone. Further experiments are necessary to determine whether electroejaculation with xylazine plus hyaluronidase is feasible for obtaining semen from Nellore bulls unaccustomed to being handled or restrained.
为验证在公牛电刺激采精过程中，硬膜外注射利多卡因、赛拉嗪或赛拉嗪加透明质酸酶可减轻疼痛和应激这一假设，八头30月龄的内洛尔公牛按随机顺序接受了向第一尾椎间隙（Co1-Co2）硬膜外腔注射生理盐水（对照）、2%利多卡因、2%赛拉嗪或2%赛拉嗪加透明质酸酶。在治疗前以及治疗期间和治疗后的预定时间间隔对心率、呼吸频率、平均动脉压、镇痛效果、动物行为和运动阻滞进行评估。对疼痛和应激进行主观评分，并评估精液质量。利多卡因的麻醉起效时间（3.0±1.2分钟）明显快于赛拉嗪或赛拉嗪加透明质酸酶（分别为8.9±1.5和5.5±2.6分钟，P=0.021和P=0.012），赛拉嗪加透明质酸酶的麻醉起效时间明显快于单独使用赛拉嗪（P=0.032）。动物行为表明，与利多卡因治疗相比，赛拉嗪或赛拉嗪加透明质酸酶治疗导致的不适更少。心率、呼吸频率和动脉压的变化在可接受范围内。在所有四种治疗过程中，所有动物均出现阴茎勃起和射精。我们的结果表明，赛拉嗪加透明质酸酶比单独使用赛拉嗪或利多卡因更有效地减轻了电刺激采精过程中的不适。需要进一步的实验来确定赛拉嗪加透明质酸酶电刺激采精对于从不习惯处理或约束的内洛尔公牛获取精液是否可行。
