Effect of butorphanol on thermal nociceptive threshold in healthy pony foals.

The research endeavored to find the effects of administering two varying dosages of butorphanol, an opioid, on the thermal nociceptive threshold in healthy pony foals. The researchers found that butorphanol increased thermal nociceptive threshold significantly in pony foals, thus proving its potential for pain management.

Objective and Hypothesis

• The purpose of this study was to determine the benefits of opioids, particularly butorphanol, in managing pain in pony foals.
• This was premised on the hypothesis that intravenous butorphanol would result in a dose-dependent increase in the thermal nociceptive threshold in both neonatal and older pony foals.

Method

• The study involved seven neonatal (age 1-2 weeks) and eleven older pony foals (age 4-8 weeks).
• Randomized crossover design was used for administering treatments including saline (0.5 ml), 0.05 mg/kg bwt butorphanol, and 0.1 mg/kg bwt butorphanol, with at least a 2 day gap between treatments.
• Assessment variables were thermal nociceptive threshold, skin temperature, and behavior score.
• A series of statistical tests were used to analyze data, including 2-way repeated measures ANOVA followed by a Holm-Sidak multiple comparison procedure where necessary.

Results

• There was a significant increase in thermal threshold following the administration of 0.1 mg/kg bwt butorphanol in both age groups.
• No significant change was evident in skin temperature over time or under different treatment conditions.
• Changes in behavior score over time were significant but not so with treatment conditions.

Conclusions

• A dose of 0.1 mg/kg butorphanol, but not 0.05 mg/kg, led to a significant growth in thermal nociceptive threshold in both neonatal and older pony foals. There was no noticeable negative effect on the behavior of the foals.
• These findings indicate that butorphanol has potential in pain management in these animals.