Antinociceptive, physiologic and biochemical effects of electroacupuncture combined with xylazine in hybrid goats

Objective: To elucidate the antinociceptive, physiologic and biochemical effects of electroacupuncture (EA) and xylazine in hybrid goats.

Study design: Prospective experimental study.

Animals: A total of 30 female hybrid goats aged 1-2 years and weighing 25 ± 2.9 kg (mean ± standard deviation).

Methods: The goats were divided into five groups and administered xylazine (0.1 mg kg^-1; group XYL.1), xylazine (0.3 mg kg^-1; group XYL.3), EA (group EA), EA + xylazine (0.1 mg kg^-1; group XYL.1-EA) and 0.9% saline (0.3 mL; control group CON). Nociceptive threshold and serum glucose concentration were measured at time 0 and at 15, 30, 45, 60 minutes and 24 hours after treatment. Nociceptive threshold was measured by passing potassium ions through the skin using potassium iontophoresis. Mean arterial pressure (MAP), heart rate (HR), respiratory frequency (f_R) and rectal temperature (RT) were recorded at times 0 and at 5, 10, 15, 20, 30, 45, 60 minutes and 24 hours. Repeated-measures analyses were performed for each response variable; p < 0.05 was considered significant for all analyses.

Results: Antinociceptive effects in groups XYL.1 and XYL.3 were increased significantly at 15-60 minutes compared with group CON. Antinociceptive effect was higher in group XYL.1-EA than groups XYL.1 or EA at 15-60 minutes (p < 0.05). No significant difference in the nociceptive threshold was recorded in groups XYL.1-EA and XYL.3, except at 30 minutes. HR, MAP, f_R, RT values were higher in group XYL.1-EA than in groups XYL.1 or XYL.3. Serum glucose concentration was higher in group XYL.3 at 15-60 minutes than in CON.

Conclusions and clinical relevance: The XYL.1 and EA combination was effective for antinociception with minimum physiologic alteration, suggesting that the combination may be a new and effective strategy for pain relief during clinical procedures in goats.