 The pig is then removed from the trough and any remaining hair is removed with a knife or a razor, and then it is again washed with hot water.Today, the animal is rendered unconscious by electrical or carbon dioxide stunning and then immediately bled by cutting the throat.For quality reasons, mechanical means of stunning such as a captive bolt pistol are not recommended although in some abattoirs they do use it and the pigs are stunned using 80 volts.