Topical anaesthesia reduces sensitivity of castration wounds in neonatal piglets.

Sabrina Lomax,Peter J White,Charissa Harris,Peter A Windsor

doi:10.1371/journal.pone.0187988

Abstract

The aim of this study was to do determine the efficacy of the topical anaesthetic Tri-Solfen® in the amelioration of the pain of castration in piglets. The trial was conducted over a three day period, and blocked across six litters with 12 piglets treated on days one and two, and 16 on day three. The piglets were randomly allocated by weight and litter to 1 of 4 treatment groups: (i) sham castration (SHAM; n = 10); (ii) surgical castration with no anaesthetic intervention (CAST; n = 10); (iii) surgical castration with post-operative topical anaesthesia (TRI; n = 10); (iv) surgical castration with a pre-operative intra-testicular lignocaine hydrochloride injection (LIG; n = 10). Wound sensitivity testing involved von Frey monofilaments of weights 4g and 300g, and an 18 gauge needle, used to stimulate the wound and surrounding skin respectively, at various pre-determined sites. Neonatal piglets receiving topical anaesthesia (Tri-Solfen®) spray into castration wounds had significantly lower wound sensitivity responses for up to 4h, compared to those castrated following intra-testicular lignocaine injection or those with no treatment. The use of topical anaesthetic is suggested as a practical and affordable method of improving piglet welfare during castration.

Highlights

Castration of male piglets is a routine husbandry procedure commonly performed within the first few days of life in commercial piggeries globally
Castration of piglets is usually performed without anaesthesia or analgesia, presumably because the anaesthetic techniques commonly used for comparable surgeries in human and veterinary medicine are either too complex, costly and time consuming to be practical or affordable for use on-farm
Due to the efficacy of this product for reducing the post surgical pain associated with castration in lambs and calves, and the similar anatomical nature of the wounds induced in porcine castration, we studied the efficacy of Tri-Solfen1 in the amelioration of the pain of castration in piglets

Summary

Introduction

Castration of male piglets is a routine husbandry procedure commonly performed within the first few days of life in commercial piggeries globally. Castration of piglets is usually performed without anaesthesia or analgesia, presumably because the anaesthetic techniques commonly used for comparable surgeries in human and veterinary medicine (general anaesthesia or sedation, local anaesthetic infiltration and / or local or regional nerve blockade) are either too complex, costly and time consuming to be practical or affordable for use on-farm. A number of publications have described the effective use of analgesic and anaesthetic interventions to address the pain associated with piglet husbandry procedures [5,6,7,8,9] these options may be considered neither practical nor affordable for large scale production systems.

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Results