Abstract
This paper examines the role of the vertebral arteries of calves in determining the time to loss of spontaneous electrocortical activity after slaughter by a throat-cut severing the soft tissues of the neck ventral to the spinal column. Four calves with the vertebral arteries ligated took 43 ± 1.3 s to lose cortical activity after the throat was cut. Four similar animals with intact vertebral arteries and the rostra1 end of the common carotid arteries clamped immediately after slaughter, to ensure that vertebral blood passed to the brain, took 51 ± 25 s to lose cortical activity. It was concluded that factors other than blood flow from the vertebral arteries contribute to the prolonged time to loss of electrocortical activity after slaughter that has been observed in some calves.