{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T14:26:14Z","timestamp":1788013574089,"version":"build-2784847793"},"reference-count":39,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T00:00:00Z","timestamp":1675728000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bangladesh Agricultural University","award":["2020\/963\/BAU"],"award-info":[{"award-number":["2020\/963\/BAU"]}]},{"name":"Bangladesh Agricultural University","award":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"],"award-info":[{"award-number":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"]}]},{"name":"Bangladesh Agricultural University","award":["LS20201342"],"award-info":[{"award-number":["LS20201342"]}]},{"name":"Bangladesh Agricultural University","award":["RAS5085"],"award-info":[{"award-number":["RAS5085"]}]},{"name":"The World Academy of Science (TWAS)","award":["2020\/963\/BAU"],"award-info":[{"award-number":["2020\/963\/BAU"]}]},{"name":"The World Academy of Science (TWAS)","award":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"],"award-info":[{"award-number":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"]}]},{"name":"The World Academy of Science (TWAS)","award":["LS20201342"],"award-info":[{"award-number":["LS20201342"]}]},{"name":"The World Academy of Science (TWAS)","award":["RAS5085"],"award-info":[{"award-number":["RAS5085"]}]},{"name":"Ministry of Education (MoE)","award":["2020\/963\/BAU"],"award-info":[{"award-number":["2020\/963\/BAU"]}]},{"name":"Ministry of Education (MoE)","award":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"],"award-info":[{"award-number":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"]}]},{"name":"Ministry of Education (MoE)","award":["LS20201342"],"award-info":[{"award-number":["LS20201342"]}]},{"name":"Ministry of Education (MoE)","award":["RAS5085"],"award-info":[{"award-number":["RAS5085"]}]},{"DOI":"10.13039\/501100004493","name":"International Atomic Energy Agency (IAEA)","doi-asserted-by":"publisher","award":["2020\/963\/BAU"],"award-info":[{"award-number":["2020\/963\/BAU"]}],"id":[{"id":"10.13039\/501100004493","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004493","name":"International Atomic Energy Agency (IAEA)","doi-asserted-by":"publisher","award":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"],"award-info":[{"award-number":["20-284 RG\/BIO\/AS_G\u2013FR3240314166"]}],"id":[{"id":"10.13039\/501100004493","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004493","name":"International Atomic Energy Agency (IAEA)","doi-asserted-by":"publisher","award":["LS20201342"],"award-info":[{"award-number":["LS20201342"]}],"id":[{"id":"10.13039\/501100004493","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004493","name":"International Atomic Energy Agency (IAEA)","doi-asserted-by":"publisher","award":["RAS5085"],"award-info":[{"award-number":["RAS5085"]}],"id":[{"id":"10.13039\/501100004493","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Low-pathogenic avian influenza (LPAI) H9N2 virus is endemic in Bangladesh, causing huge economic losses in the poultry industry. Although a considerable number of Bangladeshi LPAI H9N2 viruses have been molecularly characterized, there is inadequate information on the pathogenicity of H9N2 viruses in commercial poultry. In this study, circulating LPAI H9N2 viruses from recent field outbreaks were characterized, and their pathogenicity in commercial Sonali (crossbred) and broiler chickens was assessed. Phylogenetic analysis of currently circulating field viruses based on the hemagglutinin (HA) and neuraminidase (NA) gene sequences revealed continuous circulation of G1 lineages containing the tri-basic hemagglutinin cleavage site (HACS) motif (PAKSKR*GLF) at the HA protein. Both the LPAI susceptible Sonali and broiler chickens were infected with selected H9N2 isolates A\/chicken\/Bangladesh\/2458-LT2\/2020 or A\/chicken\/Bangladesh\/2465-LT56\/2021 using intranasal (100 \u00b5L) and intraocular (100 \u00b5L) routes with a dose of 106 EID50\/mL. Infected groups (LT_2-So1 and LT_56-So2; LT_2-Br1 and LT_56-Br2) revealed no mortality or clinical signs. However, at gross and histopathological investigation, the trachea, lungs, and intestine of the LT_2-So1 and LT_56-So2 groups displayed mild to moderate hemorrhages, congestion, and inflammation at different dpi. The LT 2-Br1 and LT 56-Br2 broiler groups showed nearly identical changes in the trachea, lungs, and intestine at various dpi, indicating no influence on pathogenicity in the two commercial bird species under study. Overall, the prominent lesions were observed up to 7 dpi and started to disappear at 10 dpi. The H9N2 viruses predominantly replicated in the respiratory tract, and higher titers of virus were shed through the oropharyngeal route than the cloacal route. Finally, this study demonstrated the continuous evolution of tri-basic HACS containing H9N2 viruses in Bangladesh with a low-pathogenic phenotype causing mild to moderate tracheitis, pneumonia, and enteritis in Sonali and commercial broiler chickens.<\/jats:p>","DOI":"10.3390\/v15020461","type":"journal-article","created":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T02:56:08Z","timestamp":1675738568000},"page":"461","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Experimental Pathogenicity of H9N2 Avian Influenza Viruses Harboring a Tri-Basic Hemagglutinin Cleavage Site in Sonali and Broiler Chickens"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3392-2496","authenticated-orcid":false,"given":"Jahan Ara","family":"Begum","sequence":"first","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ismail","family":"Hossain","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9358-1494","authenticated-orcid":false,"given":"Mohammed","family":"Nooruzzaman","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1857-7660","authenticated-orcid":false,"given":"Jacqueline","family":"King","sequence":"additional","affiliation":[{"name":"Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Suedufer 10, 17493 Greifswald-Insel Riems, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emdadul Haque","family":"Chowdhury","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2387-378X","authenticated-orcid":false,"given":"Timm C.","family":"Harder","sequence":"additional","affiliation":[{"name":"Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Suedufer 10, 17493 Greifswald-Insel Riems, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2558-2735","authenticated-orcid":false,"given":"Rokshana","family":"Parvin","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,7]]},"reference":[{"key":"ref_1","first-page":"21","article-title":"Investigation of an outbreak of low pathogenic avian influenza in poultry in Bangladesh","volume":"3","author":"Jannat","year":"2013","journal-title":"Intl. 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