{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T08:52:12Z","timestamp":1791276732646,"version":"4.1.0"},"reference-count":30,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:00:00Z","timestamp":1791244800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Background: Poultry are highly sensitive to lighting photoperiod, intensity, and color, yet little research has combined these components into a single broiler-targeted lighting program. This study evaluated an integrated dynamic LED lighting program and a further red-light dawn\/dusk addition on broiler productivity, health, and welfare. Methods: In Experiment 1, 960 male Cobb 500 broilers were reared for 42 d under a conventional white-LED program (CON) or a dynamic blue-emphasis LED program with declining intensity and a gradually shortening photoperiod (i.e., a lengthening dark period; DYN). In Experiment 2, 960 broilers were reared for 35 d under DYN or DYN with a gradual red-light dawn\/dusk transition (RDW). Growth performance, tibia strength and ash, intestinal morphology, blood corticosterone, the heterophil-to-lymphocyte ratio, physical asymmetry, tonic immobility, and inversion were measured, and an illustrative income-over-feed-cost analysis was performed. Results: DYN broilers had higher body weight and lower feed conversion ratio than CON broilers (p = 0.016 and p = 0.003, respectively), together with a lower heterophil-to-lymphocyte ratio, corticosterone, and composite asymmetry (p &lt; 0.05). RDW broilers had greater tibia breaking strengths and lower corticosterone, heterophil-to-lymphocyte ratios, and asymmetry than DYN broilers (p &lt; 0.05), with similar growth performance. Illustrative economic analysis suggested a modest income-over-feed-cost advantage for DYN over CON. Conclusions: An integrated, broiler-targeted dynamic lighting program improved growth, intestinal morphology, and stress\/fear indicators relative to a conventional program, and adding a red dawn\/dusk transition further improved skeletal and stress outcomes without compromising growth, supporting the practical, commercial-scale use of programmable LED technology to improve broiler welfare and productivity.<\/jats:p>","DOI":"10.3390\/ani16193127","type":"journal-article","created":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T08:06:47Z","timestamp":1791274007000},"page":"3127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Effect of Broiler-Targeted Lighting Programs on Productivity, Health, and Welfare"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-4562-1682","authenticated-orcid":false,"given":"Parker B.","family":"Watson","sequence":"first","affiliation":[{"name":"Department of Poultry Science, Texas A&M University, College Station, TX 77845, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily","family":"Jiral","sequence":"additional","affiliation":[{"name":"Department of Poultry Science, Texas A&M University, College Station, TX 77845, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Melinda","family":"Grimes","sequence":"additional","affiliation":[{"name":"Department of Poultry Science, Texas A&M University, College Station, TX 77845, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9371-797X","authenticated-orcid":false,"given":"Gregory S.","family":"Archer","sequence":"additional","affiliation":[{"name":"Department of Poultry Science, Texas A&M University, College Station, TX 77845, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"20150591","DOI":"10.1098\/rsif.2015.0591","article-title":"Optics of cone photoreceptors in the chicken (Gallus gallus domesticus)","volume":"12","author":"Wilby","year":"2015","journal-title":"J. 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