Abstract #M27

# M27
The effects of ethyl alcohol as a tool for pain management in neonatal pigs during castration.
Justin L. Lyles*1, Scott D. Carter1, John N. Gilliam2, Keith L. Bailey2, Johann F. Coetzee3, Michelle S. Calvo-Lorenzo1, 1Oklahoma State University, Stillwater, OK, 2Oklahoma State University College of Veterinary Medicine, Stillwater, OK, 3Iowa State University College of Veterinary Medicine, Ames, IA.

Castration without anesthesia is known to be a stressful procedure in neonatal pigs. The objective of this study was to examine the analgesic effects of ethyl alcohol (ETOH) during castration. Fifty boars across 14 litters (n = 14) were randomly assigned in a completely randomized design to 1 of 4 injection treatments: ETOH, Lidocaine, saline, or sham. One gilt from each litter was also selected as a handling control. At 3 days of age (doa), 1 ml of the respective treatment was injected into each testicle, and boars were castrated at 14 doa. Behaviors related to social cohesion, pain, and non-specific actions were continuously recorded in pens and during treatment injection and castration. Social cohesion behaviors identified how individuals acted in relation to the litter, pain-related behaviors quantified behaviors associated with pain, and non-specific behaviors signified general behaviors not associated with pain. Body weight (BW) and testicular wound scores were recorded daily post-injection and post-castration. All data were analyzed with the use of a mixed effects model with treatment as a fixed effect and pen as a random effect. The frequency of pain-related behaviors post-injection was significantly increased in the ETOH and Lidocaine groups (P < 0.05), but these groups had lower behavioral frequencies than the saline and sham treatments post-castration (P < 0.05). There were no significant differences in the frequency of non-specific behaviors after injection (P = 0.252) or castration (P = 0.456). The frequency of social cohesion behaviors did not differ across groups post-injection, but all groups had significantly greater frequencies than gilts post-castration (P < 0.05). Pigs treated with ETOH had increased wound scores post-injection versus all groups (P < 0.05). Wound healing scores did not differ across treatments post-castration (P = 0.37) and BW did not differ across treatments overall (P = 0.40). Pigs treated with ETOH behaved similarly to Lidocaine-treated pigs, but further analyses are needed to determine the effectiveness of ETOH as a practical solution to address the pain and welfare concerns of castration in pigs.

Key Words: pig, castration, pain