Why would you want to inject something into meat you're going to eat?
Actually I don't know what they use these days, but I always thought a bullet in the head to be cheap, expedient, and for the beef, painless. About as humane you can get at a slaughterhouse.
***Why would you want to inject something into meat you’re going to eat?***
Marinade?
Sorry, forgot the sarcasm tag.
Bolt Gun, mainly used in slaughterhouses, safe to use as there is no bullet. It fires a cap which in turn fires a bolt out of the barrel about eight inches.