Brain and skull lesions resulting from use of percussive bolt, cervical dislocation by stretching, cervical dislocation by crushing and blunt trauma in turkeys

Three experiments were conducted to assess brain damage resulting from percussive bolt shooting and cervical dislocation by crushing (neck crushing) in turkey hens (mean se] bodyweight 11.4 0.1] kg); percussive bolt shooting and blunt trauma in turkey toms (13.1 0.2] kg); and percussive bolt shooting, blunt trauma and cervical dislocation by stretching (neck stretching) in broiler turkeys (3.9 0.3] kg). Brain and skull damage were assessed using macroscopic and microscopic evaluations and CT. Macroscopic subcutaneous haemorrhage was significantly greater with the percussive bolt in all three experiments (hens P=0.01, toms P=0.02, broilers P=0.0003), and skull fractures were more severe for toms (P<0.0001) and broilers (P=0.03) killed with the percussive bolt versus blunt trauma. In a subsample of turkeys, microscopic brain damage was present in all turkeys killed by percussive bolt shooting (five hens, 10 toms and four broilers) and blunt trauma (nine toms and three broilers), but only in one of four turkeys killed by neck crushing and one of four turkeys killed by neck stretching. Percussive bolt shooting and blunt trauma most likely caused death by directly disrupting brain function, whereas neck stretching and neck crushing probably resulted in death from cerebral hypoxia and ischaemia.