{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:27:40Z","timestamp":1785421660377,"version":"3.56.0"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T00:00:00Z","timestamp":1775606400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015690","name":"Padjadjaran University","doi-asserted-by":"crossref","award":["4303\/B3\/DT.03.08\/2025"],"award-info":[{"award-number":["4303\/B3\/DT.03.08\/2025"]}],"id":[{"id":"10.13039\/501100015690","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100015690","name":"Padjadjaran University","doi-asserted-by":"crossref","award":["3927\/UN6. RKT\/HK.07.00\/2025"],"award-info":[{"award-number":["3927\/UN6. RKT\/HK.07.00\/2025"]}],"id":[{"id":"10.13039\/501100015690","id-type":"DOI","asserted-by":"crossref"}]},{"award":["4303\/B3\/DT.03.08\/2025"],"award-info":[{"award-number":["4303\/B3\/DT.03.08\/2025"]}],"id":[{"id":"https:\/\/ror.org\/00xqf8t64","id-type":"ROR","asserted-by":"publisher"}]},{"award":["3927\/UN6. RKT\/HK.07.00\/2025"],"award-info":[{"award-number":["3927\/UN6. RKT\/HK.07.00\/2025"]}],"id":[{"id":"https:\/\/ror.org\/00xqf8t64","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Poultry disease outbreaks are frequently multifactorial, involving complex interactions between infectious agents and environmental stressors. This report describes a case of avian influenza (AI) co-infection in a commercial broiler farm located in Majalengka, West Java, Indonesia, where a total of 11,000 birds exhibited increased mortality during the grow-out period. Diagnostic investigations included pathological examination, serological testing\u2014such as hemagglutination inhibition (HI) assays for AI H5 and H9, enzyme-linked immunosorbent assay (ELISA) for infectious bronchitis, and rapid testing for Mycoplasma gallisepticum\u2014Polymerase Chain Reaction (PCR) analysis, fecal flotation for coccidiosis, and an environmental assessment measuring ammonia levels, humidity, and heat stress index. Pathological findings revealed tracheitis, airsacculitis, thymitis, bursitis, perihepatitis, ascites, petechial hemorrhages, nephromegaly, and enteritis, indicating a complex disease process. Serological results demonstrated exposure to AI H9 and H5, with differing infection dynamics, while the uneven distribution of infectious bronchitis antibodies suggested field challenges. Additionally, partial exposure to Mycoplasma gallisepticum was observed. PCR results were negative at the time of sampling, consistent with post-infection phases. Environmental evaluation revealed elevated ammonia levels, excessive humidity, and a high heat stress index. In conclusion, the increased mortality was associated with avian influenza co-infection, complicated by secondary infections and adverse environmental conditions.<\/jats:p>","DOI":"10.3390\/vetsci13040364","type":"journal-article","created":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T11:41:18Z","timestamp":1775648478000},"page":"364","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Case of Avian Influenza Co-Infection and Multifactorial Diseases in a Broiler Chicken Farm in Majalengka, West Java, Indonesia"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6437-8921","authenticated-orcid":false,"given":"Tyagita","family":"Hartady","sequence":"first","affiliation":[{"name":"Department of Biomedical Science, Faculty of Medicine, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Indonesia"},{"name":"Study Program of Veterinary Medicine, Faculty of Medicine, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah Darmawan","family":"Sugandi","sequence":"additional","affiliation":[{"name":"Study Program of Veterinary Medicine, Faculty of Medicine, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1660-1823","authenticated-orcid":false,"given":"Muhammad","family":"Viqih","sequence":"additional","affiliation":[{"name":"PT. New Hope Farm Indonesia, Pelayangan, Gebang, Cirebon 45191, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,8]]},"reference":[{"key":"ref_1","first-page":"224","article-title":"Analysis of Broiler Chicken Meat Quality from Supermarkets and Traditional Markets in Medan City, North Sumatra","volume":"39","author":"Adji","year":"2021","journal-title":"J. Sain Vet."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Mu\u00f1oz-G\u00f3mez, V., Shaw, A.P.M., Abdykerimov, K., Abo-Shehada, M., Bulbuli, F., Charypkhan, D., Delphino, M., L\u00e9ger, A., Li, Y., and Rasmussen, P. (2025). Economic Impact of Chicken Diseases and Other Causes of Morbidity or Mortality in Backyard Farms in Low-Income and Middle-Income Countries: A systematic review and meta-analysis. BMC Vet. Res., 21.","DOI":"10.1186\/s12917-025-04549-7"},{"key":"ref_3","unstructured":"Swayne, D.E. (2020). Diseases of Poultry, Wiley-Blackwell. 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