{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T10:34:26Z","timestamp":1780569266195,"version":"3.54.1"},"reference-count":39,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,2,19]],"date-time":"2025-02-19T00:00:00Z","timestamp":1739923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"USDA National Institute of Food and Agriculture","award":["SC-1700628"],"award-info":[{"award-number":["SC-1700628"]}]},{"name":"USDA National Institute of Food and Agriculture","award":["2016204"],"award-info":[{"award-number":["2016204"]}]},{"name":"South Carolina Department of Agriculture (SCDA), Agribusiness Center for Research &amp; Entrepreneurship Competitive Grant Program (ACRE CGP","award":["SC-1700628"],"award-info":[{"award-number":["SC-1700628"]}]},{"name":"South Carolina Department of Agriculture (SCDA), Agribusiness Center for Research &amp; Entrepreneurship Competitive Grant Program (ACRE CGP","award":["2016204"],"award-info":[{"award-number":["2016204"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Research on the immunological development of lymphoid organs in chicks has been extensive, yet a significant gap exists in our understanding of innate immunity during embryonic life within the intestinal tract. This study investigated the developmental trajectory of intestinal immunity in chick embryos by evaluating basal gene expression levels of key immune markers at embryonic days (ED) 14, 17, and 20. The results indicated variable expression levels of cytokines, antimicrobial peptides (AMPs), and Toll-like receptor (TLRs) genes throughout the intestinal tract. Most cytokines and chemokines exhibited elevated expression in the cecum, while AMPs, including avian-\u03b2-defensins (AvBDs) and cathelicidins (CATHs) genes, showed increased levels in the jejunum at ED20. The findings from the developmental trajectory analysis of these genes revealed elevated expression levels of cytokines, including interferon (IFN)-\u03b3, interleukin (IL)-6, IL-13, and transforming-growth factor (TGF)-\u03b2 in the cecum at ED20. However, no consistent patterns were observed for AvBDs, CATHs, and TLRs, as their expression varied across different developmental stages of the chick embryo. These findings significantly contribute to our understanding of intestinal immune system development in chick embryos and provide a foundation for further research aimed at enhancing immune capabilities, especially in segments with lower expression levels of immunomodulatory genes.<\/jats:p>","DOI":"10.3390\/vetsci12020186","type":"journal-article","created":{"date-parts":[[2025,2,19]],"date-time":"2025-02-19T05:34:26Z","timestamp":1739943266000},"page":"186","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Differential Expression of Key Immune Markers in the Intestinal Tract of Developing Chick Embryos"],"prefix":"10.3390","volume":"12","author":[{"given":"Shreeya","family":"Sharma","sequence":"first","affiliation":[{"name":"Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2696-7079","authenticated-orcid":false,"given":"Mohammadali","family":"Alizadeh","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Scott","family":"Pratt","sequence":"additional","affiliation":[{"name":"Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0162-8521","authenticated-orcid":false,"given":"Alexis","family":"Stamatikos","sequence":"additional","affiliation":[{"name":"Department of Food, Nutrition, and Packaging Sciences, Clemson University, Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6885-0808","authenticated-orcid":false,"given":"Khaled","family":"Abdelaziz","sequence":"additional","affiliation":[{"name":"Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634, USA"},{"name":"Clemson University School of Health Research (CUSHR), Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1038\/icb.1994.18","article-title":"Development of T Cell Immune Responsiveness in the Chicken","volume":"72","author":"Lowenthal","year":"1994","journal-title":"Immunol. 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