Abstract
Nine slaughtered broiler chickens, about 50 days of age, developed systemic amyloidosis. Macroscopically, growth retardation was found in 7 cases. The livers were markedly enlarged, discolored and firm with occasional waxy appearance in all cases. The spleens were mildly to moderately swollen in 6 cases, and small white mottles were observed on the cut surface in 2 of 6 cases. Orange-yellowish materials were deposited within the articular cartilages and synovial membrane of the bilateral femorotibial joints in 1 case. Histologically, amyloid deposits, showing congophilia and green birefringence, was found in the hepatic Disse's spaces as well as the splenic ellipsoid capillary walls and their surrounding tissues in all cases. Amyloid was also deposited around the synoviocytes and in the nutritional blood vascular walls of the articular cartilage in the femorotibial joints in 1 case. Chronic purulent inflammation was observed in the femoral bone marrows in 2 cases and in the abdominal air sac in 1 case. These results suggest that systemic amyloidosis with amyloid deposits in joints could be found among broiler chickens brought to poultry processing plants.
