Abstract:
The purpose of this study was to investigate the effects of perioperative administration of oral meloxicam prior to and following the application of caustic paste to disbud neonatal dairy calves. Sixty-one 3-4-d-old Holstein heifer calves were randomly assigned to one of four treatment groups of 15-16 calves. The treatment groups were: 1) M1, caustic paste disbudding and oral meloxicam (45 mg) with a placebo 24 h later; 2) M2, treatment M1 followed by a second 45-mg dose of meloxicam 24 h later instead of placebo; 3) CONTROL, treatment M1 with placebo in place of meloxicam; and 4) SHAM, sham disbudding with placebo in place of meloxicam. Infrared thermography was used to quantify eye and horn bud temperatures. Pressure algometry was used to measure Mechanical nociceptive threshold (MNT) surrounding the horn bud. Average daily gain and body weight (BW) were obtained by weighing each animal throughout the study and calculating the changes over time. Plasma was collected and analyzed for cortisol and substance P concentrations. Substance P and cortisol decreased in all animals over time, regardless of treatment. Mean plasma substance P concentration across all time points was greater (P < 0.05) in the SHAM group than M1 or M2 but not different (P > 0.05) than the CONTROL group. The MNT and ocular temperatures decreased over time across all treatments (P < 0.05). Mean BW increased over time across all treatments (P < 0.05). A significant interaction (P < 0.05) between treatment and sampling time was observed at 12 h following treatment application for both mean horn bud temperature and the ratio between horn bud and ocular temperature. Overall, the results of this study suggest that meloxicam administration at a dose of 45 mg per animal may have limited influence as the primary modulator of pain and inflammatory response in calves that have been disbudded with caustic paste at 3 d of age.
摘要:
目的探讨在应用苛性碱糊剂前后围手术期口服美洛昔康对新生儿乳牛的影响。61只3-4日龄的荷斯坦小母牛被随机分配到四个15-16只小牛的治疗组之一。治疗组分别为:1)M1,苛性碱糊剂,24小时后口服美洛昔康(45mg),安慰剂;2)M2,治疗M1,24小时后服用第二45mg剂量的美洛昔康,而不是安慰剂;3)对照,用安慰剂代替美洛昔康治疗M1;和4)SHAM,假用安慰剂代替美洛昔康。红外热成像用于量化眼睛和角芽温度。压力测量用于测量角芽周围的机械伤害感受阈值(MNT)。通过在整个研究中对每只动物称重并计算随时间的变化来获得平均日增重和体重(BW)。收集血浆并分析皮质醇和P物质浓度。随着时间的推移,所有动物的P物质和皮质醇都会减少,不管治疗。SHAM组所有时间点的平均血浆P物质浓度均高于M1或M2(P<0.05),但与对照组相比无差异(P>0.05)。在所有治疗中,MNT和眼温随时间降低(P<0.05)。在所有治疗中平均BW随时间增加(P<0.05)。对于平均角芽温度以及角芽与眼温之间的比率,在处理应用后12小时观察到处理与采样时间之间的显着相互作用(P<0.05)。总的来说,这项研究的结果表明,每只动物45毫克剂量的美洛昔康作为疼痛和炎症反应的主要调节剂的影响可能有限,这些小牛在3d龄时已经用苛性碱糊剂进行了治疗。