{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T20:32:09Z","timestamp":1771878729479,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,2]],"date-time":"2021-06-02T00:00:00Z","timestamp":1622592000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["109-2313-B-002-052"],"award-info":[{"award-number":["109-2313-B-002-052"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006477","name":"National Taiwan University","doi-asserted-by":"publisher","award":["110L891602"],"award-info":[{"award-number":["110L891602"]}],"id":[{"id":"10.13039\/501100006477","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>During the spring, an outbreak of sudden death involving 58 birds occurred in a zoo. Histopathological examinations revealed variable numbers of intracytoplasmic basophilic microorganisms in the macrophages, hepatocytes, and renal epithelium of most birds, along with occasional botryoid intracytoplasmic inclusion bodies within histiocytes in the bursa of Fabricius. Based on the results of histopathological examinations, immunohistochemical staining, transmission electron microscopy, and polymerase chain reactions, genotype B Chlamydia psittaci infection concurrent with pigeon circovirus (PiCV) was diagnosed. A retrospective survey, including two years before the outbreak and the outbreak year, of C. psittaci and PiCV infections of dead birds in the aviaries, revealed that the outbreak was an independent episode. The findings of this study indicate that concurrent infection with C. psittaci and PiCV might lead to lethal outbreaks of chlamydiosis, particularly Streptopelia orientalis. In addition, persistently monitoring both pathogens and identifying potential PiCV carriers or transmitters might also help prevent lethal disease outbreaks.<\/jats:p>","DOI":"10.3390\/ani11061654","type":"journal-article","created":{"date-parts":[[2021,6,2]],"date-time":"2021-06-02T10:38:39Z","timestamp":1622630319000},"page":"1654","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Investigation of Lethal Concurrent Outbreak of Chlamydiosis and Pigeon Circovirus in a Zoo"],"prefix":"10.3390","volume":"11","author":[{"given":"Wei-Tao","family":"Chen","sequence":"first","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chin-Ann","family":"Teng","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Hsin","family":"Shih","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0098-0278","authenticated-orcid":false,"given":"Wei-Hsiang","family":"Huang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Fan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8877-1886","authenticated-orcid":false,"given":"Hui-Wen","family":"Chang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chian-Ren","family":"Jeng","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yen-Hsueh","family":"Lai","sequence":"additional","affiliation":[{"name":"Taipei Zoo, Taipei 116016, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun-Cheng","family":"Guo","sequence":"additional","affiliation":[{"name":"Taipei Zoo, Taipei 116016, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pao-Jung","family":"Wang","sequence":"additional","affiliation":[{"name":"Taipei Zoo, Taipei 116016, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chiu-Hung","family":"Cheng","sequence":"additional","affiliation":[{"name":"Taipei Zoo, Taipei 116016, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4971-4237","authenticated-orcid":false,"given":"Yen-Chen","family":"Chang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1111\/1348-0421.12287","article-title":"Prevalence and characterization of Chlamydia DNA in zoo animals in Japan","volume":"59","author":"Kabeya","year":"2015","journal-title":"Microbiol. 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