Pilot testing an ethanol cornual nerve block as a long-term analgesic for calf disbudding

Area of Science:

• Veterinary Medicine
• Animal Science
• Pain Management

Background:

• Disbudding calves causes significant pain, with current analgesics offering limited duration.
• Ethanol nerve blocks are explored for prolonged anesthesia, potentially mitigating disbudding-related pain.
• Combining ethanol with lidocaine may reduce procedural pain and enhance efficacy.

Purpose of the Study:

• To evaluate the efficacy of ethanol cornual nerve blocks for anesthesia in calves.
• To determine optimal ethanol concentrations and lidocaine ratios for effective pain control.
• To assess the duration of analgesia following ethanol administration.

Main Methods:

• Two pilot studies were conducted using varying concentrations (70% and 100%) and volumes of ethanol, with and without lidocaine.
• Cornual nerve blocks were administered to nondisbudded and disbudded calves of varying ages.
• Anesthesia was assessed using pinprick tests at multiple time points post-injection, up to 35 days.

Main Results:

• Ethanol provided inconsistent anesthesia, with sensation returning rapidly in many cases.
• In pilot 1, sensation loss ranged from 85% on day 0 to 3% at 35 days.
• Pilot 2 showed variable results, with some groups regaining full sensation within hours.

Conclusions:

• Ethanol cornual nerve blocks demonstrated inconsistent efficacy for prolonged anesthesia in calves.
• Current formulations and administration methods require refinement for reliable pain management post-disbudding.
• Further investigation into ethanol's role in peripheral nerve blocks for animal pain is warranted.