my 5 day old is doing the same thing !! I've been searching this computer for hours now...... It does sound like Merecks and if it's doing what mine is doing it "looks" like it as well. However.. My were supposedly vaccinated .. I'm shooting for a neurological issue or vitamins... I'm trying...
also petroleum jelly is a wonder drug for chickens and turkeys to keep them from pecking at something you don't want them to. Since it's bloody I'd start with an anti-bacterial ointment based in petroleum jelly.. they hate the taste of it and it will keep it clean from dirt as well. Good luck!