Topical Application of Lidocaine and Bupivacaine to Disbudding Wounds in Dairy Calves: Safety Toxicology and Wound Healing

摘要

Disbudding is a common, but painful procedure performed on calves to prevent horn growth. Tri-Solfen® is a combination local anaesthetic and antiseptic formulation which, applied topically to the disbudding wound, is reported to reduce calf pain. Applied in this manner, the local anaesthetics in Tri-Solfen®, lidocaine and bupivacaine, are reported to be poorly absorbed, resulting in low risk of neurological or cardiotoxic effects. The potential impacts on other blood, urine and tissue parameters and on wound healing when used in this manner, and/or accidental overdose situations are unknown, however. We performed experiments investigating (i) the safety of Tri-Solfen® (including overdose situations) and (ii) the impact of Tri-Solfen® on disbudding wound healing under field conditions. No adverse health effects were observed in Tri-Solfen®-treated animals, even those receiving 5× the recommended dose, with no clinically significant differences in measured parameters between placebo and Tri-Solfen® groups. No negative impacts on wound healing were noted. Conversely, lower levels of bacterial wound colonisation were evident, and there was reduced incidence of abnormal wounds at days 11–12 in Tri-Solfen®-treated animals.