Table 22.

ABMs for assessment of ‘State of consciousness’ after captive bolt stunning (from EFSA AHAW Panel, 2013a)

ABMs	Description
Posture	Effective stunning will result in immediate collapse or loss of posture in animals that are not restrained or prevented from doing so. Ineffectively stunned animals, on the other hand, will fail to collapse or will attempt to regain posture after collapse (EFSA AHAW Panel, 2013a).
Breathing	Effective stunning will result in the immediate onset of apnoea (absence of breathing). Ineffectively stunned animals and those recovering consciousness will start to breathe in a pattern commonly referred to as rhythmic breathing, which involves a respiratory cycle of inspiration and expiration. Rhythmic breathing can be recognised from regular movement of the flank and/or mouth and nostrils.
Corneal reflex	The corneal reflex is elicited by touching or tapping the cornea. Ineffectively stunned animals and those recovering consciousness will blink in response to the stimulus. Unconscious animals may also intermittently show a positive corneal reflex (EFSA AHAW Panel, 2013a).
Palpebral reflex	The palpebral reflex is elicited by touching or tapping a finger on the inner/outer eye canthus or eyelashes. Correctly stunned animals will not show a palpebral reflex. Ineffectively stunned animals and those recovering consciousness will blink in response to the stimulus (EFSA AHAW Panel, 2013a).
Muscle tone	Stunned animals will show general loss of muscle coinciding with the recovery of breathing and the corneal reflex if not previously stuck. Loss of muscle tone can be recognised from the completely relaxed legs, floppy ears and tail and relaxed jaws with protruding tongue. Ineffectively stunned animals and those recovering consciousness will show a righting reflex and attempts to raise the head.
Eye movements	Eye movements, including nystagmus (spontaneous rapid side‐to‐side movements of the eyeballs) or rotation of the eyeball indicate ineffective stunning, as effectively stunned animals will exhibit fixed eyes.
Vocalisations	Conscious animals may vocalise (bleating in goats and vocalisation in lambs, Goldberg, 2018), and therefore purposeful vocalisation can be used to recognise ineffective stunning or recovery of consciousness after stunning. However, not all conscious animals may vocalise (EFSA AHAW Panel, 2013a).
Body movement	Ineffectively stunned animals and those recovering consciousness will show intentional or purposeful kicking or body or head movements as a response to incision of the skin and/or insertion of the knife.
Spontaneous blinking	Conscious animals may show spontaneous blinking – the animal opens/closes eyelid on its own (fast or slow) without stimulation ‐ and therefore this sign can be used to recognise ineffective stunning or recovery of consciousness after electrical stunning. However, not all the conscious animals may show spontaneous blinking (EFSA AHAW Panel, 2013a).