Neuropathological changes produced by non-penetrating percussive captive bolt stunning of cattle.

A blunt, non-missile head injury inflicted by a non-penetrating captive bolt pistol in cattle at slaughter resulted in immediate loss of consciousness, a depressed fracture of the frontal bone and widespread subarachnoid haemorrhage, particularly beneath the impact site, in the temporal and frontal lobes, and around the brainstem. There was also invariably petechial haemorrhage in the basal ganglia and thalamus. The large concussive force applied to the cranium by the stunner was probably responsible for rendering the animal insensible and the vascular damage produced by this force and the sudden ventrocaudal acceleration of the brain after impact. These findings supported the use of this mode of stunning, followed by exsanguination, as an acceptable form of slaughter of cattle in abattoirs.