A 30-year-old Salvin's Amazon parrot (Amazona autumnalis salvini) with a history of a lifelong poor diet and inappropriate housing was presented in lateral recumbency to a veterinary teaching hospital for further evaluation. Radiological and ultrasonographic examination revealed a mild proventricular dilatation, mild hepatomegaly, signs of enteritis and airsacculitis. The main laboratory findings included a mild macrocytic hyperchromic anaemia, hypoglobulinaemia, decreased bile acids and increased alkaline phosphatase. In this bird a liver pathology was suspected because of the clinical, laboratory and ultrasonographic findings. The bird was treated with supportive care and metabolic aids. After initial improvement of the clinical signs, the bird's condition deteriorated and it died. Pathological findings revealed an endocarditis and myocarditis due to Lactobacillus jensenii and a bacteraemia. Endocarditis due to Lactobacillus sp. is a rare phenomenon in humans not yet described in animals. It is associated with severe underlying illnesses leading to translocation of otherwise non-pathogenic bacteria in the bloodstream. A similar pattern might be assumed in animals with compromised immunity.