Previous studies have found that blunt force was the most satisfactory method of euthanizing young pigs. The researchers tested four different methods and made decisions based on  speed of application, human resource and input cost, animal restraint required, and failure rate.  Although based on subjective aesthetics and physical application, manual blunt force trauma was found to be unacceptable. The researchers concluded by saying ” Considering animal welfare metrics in isolation, controlled blunt force trauma was superior to all other techniques attempted.”