This paper describes the clinical, hematological, biochemical, echocardiographic, electrocardiographic and pathological findings in 19 cows with pulmonic valve vegetations. Results were compared with those of 10 apparently clinically healthy cows. Clinically, the most striking clinical findings were recurrent fever, dyspnea, tachycardia, weight loss or decreased milk production. Epistaxis and/or hemoptysis were observed in 5 diseased cows. A presumptive diagnosis of pulmonic valve endocarditis was made primarily on the basis of auscultation of the valve at the left 3rd intercostal space with history of fever. Thirteen of the animals had leukocytosis; 11 had neutrophilia and 3 had lymphopenia. Serum chemistry revealed hyperproteinemia, hypoalbuminemia and hypergammaglobulinemia. High serum activities of lactate dehydrogenase (LDH) were also observed. Arterial blood gas analysis showed metabolic acidosis in 14 cows and elevated bicarbonate concentration in 4 cows. A definitive diagnosis was then done by echocardiography and electrocardiography (ECG). Confirmatory diagnosis was finally made after slaughter of 17 cases. Postmortem lesions included also thrombosis of the pulmonary artery inside the lung with secondary pneumonia. Data obtained from this study clearly demonstrate the superior diagnostic effects of echocardiography and ECG in cows with pulmonic vegetative endocarditis.