Spontaneously occurring alimentary osteofluorosis associated with proliferative gastroduodenopathy in rabbits

Growing rabbits from two rabbitries, fed with commercial concentrates and hay, developed painful thickenings of the extremities. Four rabbits from each farm were clinically examined and necropsied. All animals showed multiple moderate to severe osseous proliferations of extremities and mandibles and a mild to severe proliferative gastroduodenopathy. Histologically, periosteal and endosteal hyperostosis and a mild to severe proliferation of the gastric and duodenal mucosa were noted. Bone analyses revealed 12,700 and 15,000 microg fluoride per gram of bone ash in affected rabbits, compared with 550 microg fluoride in a control animal. A highly elevated fluoride content was found in concentrates. Vitamin A levels were moderately increased only in one concentrate, and copper levels were normal. Results indicate that alimentary fluoride intoxication caused prominent bony proliferations in the examined rabbits. Whether the proliferative gastroduodenopathy is related to the elevated fluoride intake or represents an incidentally occurring secondary disease remains to be determined.