They might be holly croppers. They are a heavy built bird, with the head slightly back that shakes a lot. I have several friends that have them, but I do not care for them.
Many years ago the standard fantail was also called a shaker. But other then that There is not a breed called that. Several breeds will have the shakey neck. Mookies, fans, ect.i was a swap meet and saw theses pigeons the guy called them shaker pigeons i never saw them before does anyone have any for sale or no where i could find some. also is that what there callled thanks