Many years ago I did get a load of frozen mice shipped to me with the thoats cut. I can't remember the name of the place I ordered them from, but I believe they were from AZ and they went out of business a long time ago. The cuts were not side to side but from chin to sternum. I assumed that these had been lab mice that had been euthanized and something removed from their throats to study under a microscope or something like that. I never really thought much about it until reading about these throat cut rats.