High incidence up to 70% of gout was found in inbred chickens of Fayoumi strain fed a 40% protein diet. Mean plasma uric acid levels of gouty and non-gouty male chickens of Fayoumi. strain and white Leghorn. strain fed a 40% protein diet, were 21.5,8.5,5.0 mg/dl, respectively. Disappearance curves of plasma uric acid after intravenous injection of [U-14C]uric acid in both non-gouty and gouty chickens were parallel, although uric acid pool size was much larger in gouty chickens than in non-gouty ones. Next, urine was collected through cloaca after the fecal outlet was artificially made at the abdominal wall. Urinary [14C] uric acid was much more in gouty chickens compared with non-gouty chickens, after [U-14C]glycine was intravenously injected. These findings showed that the. cause of hyperuricemia of gouty chickens was the accelerated uric acid synthesis rather than the impared urinary excretion of uric acid. Activities of hepatic enzymes such as hypoxanthine-guanine-phosphoribosyltransferase, PPRP synthetase, PPRP amidotransferase, glutaminase, glutamine synthetase, etc. were compared between non-gouty and gouty chickens. Feed back inhibition of hepatic amidotransferase by IMP, GNP or AMP was observed in a smaller extent in gouty chickens than in nongouty ones. This chicken will be used as an animal model of at least a type of human gout.