{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T12:34:24Z","timestamp":1793450064769,"version":"4.5.0"},"reference-count":29,"publisher":"American Association of Avian Pathologists (AAAP)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Avian Diseases"],"published-print":{"date-parts":[[2020,2,19]]},"abstract":"<jats:p>This article outlines pathomorphologic findings of a study involving commercial mule ducks with confirmed influenza A H5N8 infections after a series of outbreaks in Bulgaria. Examinations were carried out after performing necropsy on dead birds from three different age groups (up to 15, 20 to 30, and 40+ days of age) fattened on different farms. Among birds of all ages, gross lesions were present as lesions affecting the heart. Histologically, the myocardium exhibited severe intermyofibrillar edema, moderate to massive hemorrhages, and degenerative changes. All lesions resulted in single or multiple and small to massive myocardial infarctions. Other affected organs included the brain, lungs, liver, spleen, and pancreas. Nonpurulent lymphocytic encephalitis was found postmortem in ducks that had shown prior clinical nervous signs. Among ducks of all ages, a viral antigen in the cardiomyocytes and the epithelium of air capillaries was found through immunohistochemical detection methods. The results of the present study allowed us to conclude that the highly pathogenic avian influenza A H5N8 viral infection may manifest itself as a systemic illness in commercial mule ducks with septicemic lesions, resulting in high morbidity and mortality rates of up to 100%. Pathomorphologic lesions were somewhat different from those previously reported in wild waterfowl.<\/jats:p>","DOI":"10.1637\/0005-2086-64.2.203","type":"journal-article","created":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T09:27:16Z","timestamp":1592213236000},"page":"203-209","source":"Crossref","is-referenced-by-count":9,"title":["Pathologic Evaluation of Influenza A H5N8 Infection Outbreaks in Mule Ducks in Bulgaria"],"prefix":"10.1637","volume":"64","author":[{"given":"Ivan","family":"Dinev","sequence":"first","affiliation":[{"name":"Department of General and Clinical Pathology, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Zarkov","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Infection and Parasite Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela V.","family":"Goujgoulova","sequence":"additional","affiliation":[{"name":"National Diagnostic Research Veterinary Medical Institute, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgi M.","family":"Stoimenov","sequence":"additional","affiliation":[{"name":"Department of Infectious Pathology and Food Hygiene, Faculty of Veterinary Medicine, University of Forestry, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgi","family":"Georgiev","sequence":"additional","affiliation":[{"name":"Risk Assessment Center on Food Chain, Ministry of Agriculture, Food and Forestry, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dian","family":"Kanakov","sequence":"additional","affiliation":[{"name":"Department of Internal Noninfectious Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1212","reference":[{"key":"1","doi-asserted-by":"crossref","unstructured":"DJ. 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