Twitching in veterinary procedures: How does this technique subdue horses?

Investigating conditioned pain modulation in horses: can the lip-twitch be used as a conditioning stimulus?

Study objective was to evaluate whether the application of a lip twitch could be proposed as conditioning stimulus in the context of a novel Conditioned Pain Modulation (CPM) assessment paradigm for use in horses. The study was a prospective, experimental, randomized trial. Twelve healthy horses were evaluated in two experimental sessions. The lip twitch was used as the conditioning stimulus in both sessions; electrical stimulation was used as the test stimulus in one session, while mechanical and thermal stimulations were used in the other. Differences between thresholds recorded before and during twitching (Δ) as well as their percent (%) change were computed for each stimulation modality as a measure of CPM. Heart rate and respiratory rate were recorded throughout the experiments to monitor physiological reactions, while the general level of stress and aversiveness toward twitching were scored using ad hoc behavioural scales. Based on these scores, interruption criteria were defined. Ten and seven horses completed the electrical and mechanical/thermal experimental sessions respectively. For electrical stimulation, median (IQR) Δ was -2.8 (-3.9, -1.1) mA and% change 87.9 (65.7-118.2)%; for mechanical stimulation, Δ was -18.2 (-6.4, -21.4) N and% change 343.5 (140, 365.3)%; for thermal stimulation, Δ was -3.1 (-9.2, -2.1)°C, while% change was not calculated. Heart rate and respiratory rates varied significantly over time, with higher values recorded during twitching. Median stress and aversion scores did not differ between the two sessions. As lip twitching consistently affected thresholds to all stimulation modalities, it can be proposed as effective conditioning method for CPM assessment in horses. The exclusion of subjects due to severe aversion shows that this paradigm cannot be indistinctively applied to all horses and that stringent interruption criteria are necessary to guarantee adequate welfare during testing.

Moving toward Fear-Free Husbandry and Veterinary Care for Horses

Husbandry and veterinary procedures have the potential to generate fear and stress in animals. In horses, the associated responses can pose a significant safety risk to the human personnel involved in the procedure, as well as to the animal itself. Traditionally, physical restraint, punishment, and/or threat of an aversive, have been the most common strategies used to achieve compliance from the horse. However, from a welfare perspective, this is less than ideal. This approach also has the potential for creating a more dangerous response from the horse in future similar situations. When caring for companion animals, and captive animals within zoological facilities, there has been a steady transition away from this approach, and toward strategies aimed at reducing fear and stress during veterinary visits and when undertaking routine husbandry procedures. This review discusses the current approaches to horse care and training, the strategies being used in other animal sectors, and potential strategies for improving human safety, as well as the horse's experience, during husbandry and veterinary procedures.

Effects of blindfolding and tail bending of Egyptian water buffaloes on their behavioural reactivity and physiological responses to pain induction

This experiment was carried out to determine the effect of blindfold and tail bend during restraint of Egyptian buffaloes on behavioural reactivity and physiological responses to stressful handling procedures. Twenty-four buffalo bulls, naïve to the testing situation, were arbitrarily assigned to either blindfold (visual restriction) (BF), tail bending (physical control) (TB) or control (CT) (no visual restriction or physical control) treatment during restraint. For three minutes each, during veterinary procedures animals entered the squeeze chute and were subjected to testing trials. Heart rate (HR), respiratory rate (RR) and various behaviours of reactivity were recorded. Average HR and RR decreased in both TB and BF bulls but the reduction was greater in BF bulls. Use of the blindfold and tail bend decreased behavioural indicators of reactivity including: chest chute forcing, head move, kicking and struggling. The reduction was greater in BF bulls in the case of use of the chest chute and struggling. Both tail bend and blindfolded buffaloes decreased behavioural and physiological indicators of stress but BF appeared more beneficial, and may therefore be recommended to reduce stress accompanying routine veterinary examination of buffaloes.