Effect of Topically Applied Anaesthetic Formulation on the Sensitivity of Scoop Dehorning Wounds in Calves

Abstract

The post-operative effects of three formulations of topical anaesthetic and a cornual nerve block on the sensitivity of scoop dehorning wounds in calves were compared in two trials. In Trial 1, 21 female Holstein dairy calves aged 8 to 24 weeks were randomly allocated to two groups: (1) scoop dehorning with a post-operative application of a novel topical anaesthetic powder (DTAP, n = 10); and (2) scoop dehorning with a post-operative application of a novel topical anaesthetic ethanol liquid (DTAE, n = 11). In Trial 2, 18 castrated male and 18 female Hereford beef calves aged 16 to 20 weeks were randomly allocated to four groups: (1) scoop dehorning with a pre-operative cornual nerve block of lignocaine (DCB, n = 9); (2) scoop dehorning with a post-operative application of the novel topical anaesthetic ethanol liquid from Trial 1 (DTAE, n = 9); (3) scoop dehorning with a post-operative application of a topical anaesthetic gel (DTAG, n = 9); and (4) sham dehorning (CON, n = 9). Sensitivity was assessed by scoring the behavioural response of calves to stimulation of the wound or skin at time points before and after treatment. In Trial 1, DTAP calves had a greater probability of displaying more severe responses than DTAE calves at 90 and 180 min (P < 0.001). In Trial 2, at 1 h, DTAG calves had a greater probability of displaying more severe responses than CON calves. At 2 h onwards, all dehorned calves had a greater probability of displaying more severe responses than CON calves (P < 0.001). There were no differences between the responses of DCB, DTAG and DTAE calves at any time point. Topical anaesthetic formulations result in almost immediate but temporary anaesthesia of the wound following scoop dehorning in calves and may provide a practical option for pain relief on-farm.

Welfare Effects of the Use of a Combination of Local Anesthesia and NSAID for Disbudding Analgesia in Dairy Calves—Reviewed Across Different Welfare Concerns

“…The ability to recruit otherwise silent nociceptors may play a role in primary hyperalgesia after burn injury ( 71 ). Increased sensitivity of the injured as well as surrounding skin have been reported from horn removal studies in calves, typically quantified as mechanical nociceptive threshold when stimulated by an algometer (MNT) ( 41 , 64 ) or by use of von Frey filaments ( 25 , 73 , 74 ).…”

Effects of a topically applied anaesthetic on the behaviour, pain sensitivity and weight gain of dairy calves following thermocautery disbudding with a local anaesthetic

“…This product was evaluated in 30 Holstein-Friesian, 2 month old calves, when applied after scoop dehorning, compared to no pain relief, and was found to reduce or remove responses to mechanical stimulation from 4-24 hours after application (Espinoza et al 2013). In another study the topical anaesthetic, applied after scoop dehorning, was compared with a cornual nerve block applied prior to dehorning, and found no difference in pain sensitivity after dehorning (McCarthy et al 2016). However this study had errors in its statistical analysis and was grossly underpowered to detect any differences.…”

Evaluating treatments with topical anaesthetic and buccal meloxicam for pain and inflammation caused by amputation dehorning of calves

“…A topical anaesthetic (TA) gel, Tri-Solfen ® (Bayer Animal Health, NSW, Australia), originally developed for spray-on application to open wounds induced during mulesing of lambs, has recently been registered for tail docking of lambs and surgical castration of lambs and calves [ 11 , 12 ]. This TA has also been shown to provide post-operative anaesthesia of dehorning wounds comparable to that provided by a cornual nerve block of lignocaine [ 13 ]. In addition to TA, a gel containing the non-steroidal anti-inflammatory drug (NSAID) meloxicam, Ilium ® Buccalgesic OTM (Troy Laboratories Ltd Pty, NSW, Australia), was developed for administration into the buccal cavity for oral trans-mucosal delivery.…”