Xen- (prefix): Foreign or other. As in: 1  Xenoantigen -- An antigen that is found in more than one species.  Xenograft -- A surgical graft of tissue from one species to an unlike species, genus or family.
Diet. Snow Geese feed almost exclusively on plant material. During the breeding season, they eat many seeds, leaves, and roots of aquatic vegetation. The very young birds feed on invertebrates. Berries become more important in the fall. In winter, waste grain from agricultural fields has become a primary food source.
Quick Answer. Geese are primarily herbivores and usually eat tender grasses and plant materials, such as roots, leaves, stems and sprouts. Geese may eat wheat and pellets, which is a common diet for farm-raised geese. Geese may eat bread, but they do not derive much nutrition from it. They also eat insects, fish, rice and corn.