Adjuvant experimental polyarthritis

Among the several methods used for the reproduction of an experimental arthritis in various species and strains of laboratory animals, the one induced by the injection of Freund adjuvant in rats seems to be the most attractive. Although no experimental arthritis satisfactorily resembles human rheumatoid arthritis, adjuvant polyarthritis appears to be highly promising because of its systemic manifestations, the clinical course, the migratory polyarthritis, the serological alterations, the roentgenologic changes and the histology. The disease is reproduced by a single subcutaneous injection of the rat’s tail with 0.8 mg. of dead mycobacterium butyricum suspended in 0.1 ml. paraffin oil.