Electrical stimulation (tetanic mode) was applied to each antler approximately 25 mm distal to the pedicle/antler junction before, and at intervals up to 1 hour after, application of treatments at a level required to produce a head/neck avoidance behavioural response.\n\nIn a third experiment, the two electrical stimulation protocols used above were directly compared by measuring the response of stags (n= 8) to one protocol on each pedicle/antler prior to, and at intervals for 1 hour Y-27632 molecular weight after, application

of a rubber ring.\n\nAt the end of each treatment in all three experiments, analgesia of the antler was established as a nil behavioural response of the stag to a saw cut to the antler

(the ‘nick test’).\n\nRESULTS: For both methods of application of a ring the minimum electrical stimulation required distal to the ring to elicit a reflex response increased from around 16 to 55 mA by 60 minutes. In contrast, the electrical stimulation required proximal to the ring remained low (similar Bafilomycin A1 to 17.0 mA) throughout. No stag subjected to either of the methods of application responded to the nick test 60 minutes after application of the ring.\n\nThe electrical stimulation required to produce a behavioural response increased very rapidly in stags treated with local anaesthetic and at a slower rate in those treated with the Selleck IWR-1-endo cabletie method but showed no significant increase in control stags. After 4 and 30 minutes, for

local anaesthesia and the cable-tie method, respectively, 95% of stags were not responding to 80 mA. A significantly greater proportion of stags with antlers treated with local anaesthetic and the cable-tie method did not respond to the nick test than controls, and there was no significant difference in the frequency of the response between stags with treated antlers.\n\nThe minimum current required to produce a response proximal to a rubber ring was slightly higher on average for train-of-four electrical stimulus (mean 18.1 (SD 2.6) mA) than for the tetanic mode (mean 11.9 (SD 2.5) mA). The increase in minimum current required to produce the respective response to stimulation distal to the ring was similar for both methods, although the maximum predicted value (67.4 mA) was lower for train-of-four than for the tetanic mode (84.5 mA). No stag responded to the nick test >= 60 minutes after application of the ring.\n\nCONCLUSIONS: The cable-tie method was no different from the standard method as a procedure for producing analgesia in the antlers of yearling stags and should be accepted as an appropriate procedure for applying analgesic rings to yearling stags.