Doherty T J, Kattesh H G, Adcock R J, Welborn M G, Saxton A M, Morrow J L, Dailey J W
Department of Large Animal Clinical Sciences, The University of Tennessee, College of Veterinary Medicine, Knoxville 37996, USA.
J Dairy Sci. 2007 Sep;90(9):4232-9. doi: 10.3168/jds.2007-0080.
The objective of this study was to more fully define the surgical stress response to dehorning by heat cauterization in dairy calves by measuring behavioral, hormonal, inflammatory, and immunological markers of stress and to determine whether a nerve block of the surgical site with a concentrated solution of lidocaine (5%) reduces the degree of stress. Thirty-two 10- to 12-wk-old female Holstein calves were randomly allotted to 1 of 4 treatments: 5% lidocaine followed by dehorning, 2% lidocaine followed by dehorning, saline followed by dehorning, or 5% lidocaine followed by sham dehorning. Plasma cortisol concentration was measured in blood samples collected via a jugular catheter at -0.5, 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 9, 12, 24, 48, and 72 h. Various other blood constituents were measured in samples collected at -0.5, 12, 24, 48, and 72 h. Feeding, drinking, scratching, grooming, rubbing, licking, and inactivity behaviors were observed in the standing and recumbent positions using a 10-min scan sampling method analyzed on a time period and daily basis for 72 h following the dehorning procedure. The frequency of vocalization, kicking, and lying in the chute during the dehorning procedure were also assessed. The overall plasma cortisol concentrations were higher in calves subjected to dehorning than in control calves. Compared with the control group, the saline-treated calves had a higher cortisol concentration at 30 and 60 min postdehorning. Plasma cortisol concentrations were higher in all groups at 30 min postdehorning than at other sampling times. The percentage of circulating neutrophils and the neutrophil:lymphocyte ratio were increased in the saline and 2% lidocaine group. Total plasma protein, fibrinogen, and alpha1-acid glycoprotein concentrations were similar among treatments. The behavioral response to dehorning, as manifested by kicking while in the chute, was greater in the saline and 2% lidocaine group than in the control or 5% lidocaine treatment groups. In the postdehorning period, the percentage of time calves spent performing various maintenance behaviors did not differ among treatments. Thus, injection of 5% lidocaine may not provide any added comfort after the dehorning but may decrease the overall stress response during the procedure.
本研究的目的是通过测量应激的行为、激素、炎症和免疫指标，更全面地确定热灼去角术对奶牛犊牛手术应激反应的影响，并确定用高浓度利多卡因（5%）对手术部位进行神经阻滞是否能减轻应激程度。32头10至12周龄的雌性荷斯坦犊牛被随机分配到4种处理中的1种：5%利多卡因后去角、2%利多卡因后去角、生理盐水后去角或5%利多卡因后假去角。在-0.5、0、0.5、1、1.5、2、2.5、3、3.5、4、6、9、12、24、48和72小时，通过颈静脉导管采集血样，测量血浆皮质醇浓度。在-0.5、12、24、48和72小时采集的样本中测量各种其他血液成分。采用10分钟扫描取样法，在去角术后72小时内，按时间段和每日观察站立和躺卧姿势下的采食、饮水、抓挠、梳理、摩擦、舔舐和静止行为。还评估了去角过程中发声、踢腿和躺在斜槽中的频率。去角犊牛的总体血浆皮质醇浓度高于对照犊牛。与对照组相比，生理盐水处理的犊牛在去角后30和60分钟时皮质醇浓度更高。去角后30分钟时所有组的血浆皮质醇浓度均高于其他取样时间。生理盐水组和2%利多卡因组循环中性粒细胞百分比和中性粒细胞与淋巴细胞比率增加。各处理间血浆总蛋白、纤维蛋白原和α1-酸性糖蛋白浓度相似。生理盐水组和2%利多卡因组在斜槽中踢腿表现出的对去角的行为反应比对照组或5%利多卡因处理组更大。在去角后时期，犊牛用于进行各种维持行为的时间百分比在各处理间没有差异。因此，注射5%利多卡因可能在去角后不会提供任何额外的舒适感，但可能会降低手术过程中的总体应激反应。
