Comparison of morphine and butorphanol as pre-anaesthetic agents in combination with romifidine for field castration in ponies.

This research aims to compare the effectiveness of two different combinations of sedative drugs used for anaesthesia in ponies undergoing castration procedures. It was found that the combination of romifidine and butorphanol provided a better quality of sedation and maintenance of anaesthesia compared to the combination of romifidine and morphine or romifidine with saline.

Objective and Methodology

• The main objective of this experiment was to compare and evaluate the effects of two different alpha2 agonist-opioid combinations used as pre-operative sedatives. The substances tested were combinations of intravenous romifidine and butorphanol, romifidine and morphine, and romifidine with saline.
• A total of 54 ponies, all due for castration, were used in this randomized clinical trial. They were divided into groups and each group was administered one of the drug combinations. Ketamine was used to induce the anaesthesia and additional doses of romifidine and ketamine were given as required to maintain the anaesthesia.

Measurements and Observations

• The researchers assessed the quality of sedation, induction of anaesthesia, maintenance of anaesthesia, and recovery. They also evaluated the surgical condition.
• The effects of each drug combination were judged using a visual analogue scale scoring system. The researchers took note of the heart and respiratory rates, the recovery time, and the number of repeated anaesthetic doses needed during the procedure for each group.

Findings

• According to the results, anaesthesia was adequately maintained in all the ponies. There were no anaesthetic complications.
• The group of ponies that received the combination of romifidine and butorphanol experienced significantly better sedation compared to the group that received romifidine and saline.
• The overall quality of the anaesthesia was better in the butorphanol group compared to the morphine group and the saline group.
• The study observed muscle twitches in the saline and morphine groups. Furthermore, recovery time, surgical conditions, and the number of additional anaesthetic doses needed during the procedure did not show significant differences between groups.

Conclusion

• The research concluded that the combination of romifidine and butorphanol provided better sedation and smoother maintenance of anaesthesia.
• The combination of romifidine and morphine can also be considered suitable but less effective. The use of morphine or butorphanol in combination with alpha2 agonists needs further investigation to assess their pain-relieving effects.