Yersinia pseudotuberculosis, serogroup 0:1A, infection in two Amazon parrots (Amazona aestiva and Amazona oratrix) with hepatic hemosiderosis

Abstract: Necropsies were conducted on a female blue-fronted Amazon (Amazona aestiva) and a female yellow-headed Amazon (Amazona oratrix) that died following depression, ruffled feathers, diarrhea and biliverdin in the urine. Gross and microscopic examinations revealed multifocal necrosis in the liver, spleen, lungs, kidney, intestine and heart caused by acute bacteremia. Yersinia pseudotuberculosis, serogroup O:1a, was isolated by culturing from the visceral lesions in the liver, intestine and spleen. Virulence gene analysis showed the presence of the inv gene and the complete pathogenicity island: IS100, psn, yptE, irp1, irp2 ybtP-ybtQ, ybtX-ybtS, int asnT-Int. Histopathologic findings and chemical analysis also demonstrated hepatic hemosiderosis. As has been demonstrated in other species, we suggest that hemosiderosis may also predispose Amazona spp. to systemic infection with Yersinia pseudotuberculosis following enteric disease.