{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T18:32:34Z","timestamp":1786818754083,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,3,11]],"date-time":"2021-03-11T00:00:00Z","timestamp":1615420800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"BIOMIN America Inc.","award":["03082017"],"award-info":[{"award-number":["03082017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The aim of this experiment was to evaluate the effect of a phytogenic feed additive (PFA) on growth performance and nutrient digestibility of broilers fed corn and soybean meal-based diets containing two different levels of crude protein. A 2 \u00d7 2 completely randomized factorial arrangement (eight replicates\/treatment, 30 birds\/replicate) was conducted with a positive control (PC) and negative control (NC) containing crude protein at standard or reduced by 1.5% (equivalent to a reduction of 15 g\/kg), respectively, and supplementation of PFA at 0 or 125 ppm of diet. There were no significant interactions found between PFA and CP levels in the current study. Main effect analysis showed that during 0\u201342 d of age NC diets decreased body weight gain (p &lt; 0.05), but increased feed intake (p &lt; 0.05) and feed conversion ratio (FCR, p &lt; 0.01), whereas supplementation of PFA resulted in a lower FCR (p &lt; 0.01). The ileal nutrient digestibility was reduced (p &lt; 0.05) in the broilers fed a reduced protein diet at 21 d compared to the standard protein level group, but there were no effects for PFA levels. Similarly, supplementing PFAs showed no effects on digestive enzyme (Alkaline phosphatase, amylase, and lipase) activity in jejunal digesta and jejunal brush border enzyme (maltase, sucrase, and aminopeptidase) activity. Supplementation of PFA downregulated (p &lt; 0.05) the mRNA expressions of cytochrome P450 1A and interleukin 6 in the ileum but had no effects on nutrient transporter genes in the jejunum. In conclusion, supplementation of PFA reduced broiler FCR during the whole grow-out period and positively regulated the immune responses in the ileum.<\/jats:p>","DOI":"10.3390\/ani11030775","type":"journal-article","created":{"date-parts":[[2021,3,11]],"date-time":"2021-03-11T04:46:53Z","timestamp":1615438013000},"page":"775","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Effect of a Phytogenic Feed Additive on Growth Performance, Nutrient Digestion, and Immune Response in Broiler-Fed Diets with Two Different Levels of Crude Protein"],"prefix":"10.3390","volume":"11","author":[{"given":"Jinquan","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Poultry Science, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shengchen","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Poultry Science, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4008-3387","authenticated-orcid":false,"given":"Chasity","family":"Pender","sequence":"additional","affiliation":[{"name":"BIOMIN America Inc., Overland Park, KS 66210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raj","family":"Murugesan","sequence":"additional","affiliation":[{"name":"BIOMIN America Inc., Overland Park, KS 66210, USA"},{"name":"BIOMIN Holding GmbH, 3130 Getzersdorf, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7365-1344","authenticated-orcid":false,"given":"Basharat","family":"Syed","sequence":"additional","affiliation":[{"name":"BIOMIN Holding GmbH, 3130 Getzersdorf, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0005-352X","authenticated-orcid":false,"given":"Woo Kyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Poultry Science, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,11]]},"reference":[{"key":"ref_1","unstructured":"The European Parliament and the Council of the European Union (2003). Regulation No 1831\/2003 of the European Parliament and Council of 22 September 2003 on additives for use in animal nutrition. Off. J. Eur. Union, 268, 29\u201343."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1080\/00071660500191056","article-title":"Use of active substances of plant origin in chicken diets based on maize and locally grown cereals","volume":"46","author":"Jamroz","year":"2005","journal-title":"Br. Poult. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/j.livsci.2011.12.008","article-title":"Effects of supplemental essential oil on growth performance, lipid metabolites and immunity, intestinal characteristics, microbiota and carcass traits in broilers","volume":"144","author":"Hong","year":"2012","journal-title":"Livest. Sci."},{"key":"ref_4","first-page":"21","article-title":"Pender. Phytogenic feed additives as an alternative to antibiotic growth promoters in broiler chickens","volume":"2","author":"Murugesan","year":"2015","journal-title":"Front. Vet. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.anifeedsci.2017.09.013","article-title":"Effects of dietary protein levels and multienzyme supplementation on growth performance and markers of gut health of broilers fed a miscellaneous meal based diet","volume":"234","author":"Liu","year":"2017","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_6","first-page":"233","article-title":"Tetramethylpyrazine attenuates necrotic enteritis by reducing gut oxidative stress, inflammation, opportunistic bacteria and endotoxins of broilers","volume":"82","author":"Liu","year":"2018","journal-title":"Euro. Poult. Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1156","DOI":"10.1093\/ps\/81.8.1156","article-title":"Effect of low-protein diets on growth performance and body composition of broiler chicks","volume":"81","author":"Bregendahl","year":"2002","journal-title":"Poult. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1017\/S0043933916000477","article-title":"Reduction of nitrogen excretion and emissions from poultry: A review for conventional poultry","volume":"72","author":"Chalova","year":"2016","journal-title":"Worlds Poult. Sci. J."},{"key":"ref_9","first-page":"111","article-title":"Effects of antimicrobial feed additives on gut microbiology and blood parameters of weaned piglets","volume":"59","author":"Kroismayr","year":"2008","journal-title":"Bodenkultur"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"630","DOI":"10.1111\/jpn.12842","article-title":"Performance, rumen fermentation and blood metabolites of dairy calves fed starter mixtures supplemented with herbal plants, essential oils or monensin","volume":"102","author":"Ghasemi","year":"2018","journal-title":"J. Anim. Physiol. Anim. Nutr."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"99","DOI":"10.3354\/dao03235","article-title":"Phytogenic feed-additive effects on channel catfish rhamnose-binding lectin levels, and susceptibility to Edwardsiella ictaluri","volume":"129","author":"Peterson","year":"2018","journal-title":"Dis. Aquat. Org."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"114575","DOI":"10.1016\/j.anifeedsci.2020.114575","article-title":"Evaluation of a phytogenic feed additive on performance, nutrient digestion, and absorption in turkey poults","volume":"267","author":"Zumbaugh","year":"2020","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"264","DOI":"10.2141\/jpsa.0150113","article-title":"Phytogenic Administration and Reduction of Dietary Energy and Protein Levels Affects Growth Performance, Nutrient Digestibility and Antioxidant Status of Broilers","volume":"53","author":"Paraskeuas","year":"2016","journal-title":"J. Poult. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2220","DOI":"10.3382\/ps\/pey588","article-title":"Modulation of broiler gut microbiota and gene expression of Toll-like receptors and tight junction proteins by diet type and inclusion of phytogenics","volume":"98","author":"Paraskeuas","year":"2019","journal-title":"Poult. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1093\/ps\/83.4.669","article-title":"The effect of two different blends of essential oil components on the proliferation of Clostridium perfringens in the intestines of broiler chickens","volume":"83","author":"Mitsch","year":"2004","journal-title":"Poult. Sci."},{"key":"ref_16","first-page":"186","article-title":"Using yucca and\/or phytogenics on alleviating negative effects of necrotic enteritis in broilers","volume":"93","author":"Zheng","year":"2019","journal-title":"Poult. Sci. Ann. Meet."},{"key":"ref_17","unstructured":"Cobb Vantress Inc. (2018). Cobb500 Broiler Performance & Nutrition Supplement Guide, Cobb Vantress Inc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1016\/j.japr.2020.04.004","article-title":"Effects of dietary energy level and 1,3-diacylglycerol on growth performance and carcass yield in broilers","volume":"29","author":"Wang","year":"2020","journal-title":"J. Appl. Poult. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1017\/S002185960001546X","article-title":"The determination of chromic oxide in faeces samples by atomic absorption spectrophotometry","volume":"59","author":"Williams","year":"1962","journal-title":"J. Agric. Sci."},{"key":"ref_20","unstructured":"AOAC (1996). Official Method of Analysis of the Association of Official Analytical Chemists, AOAC International."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1006\/meth.2001.1262","article-title":"Analysis of relative gene expression data using real-time quantitative PCR and the 2-\u0394\u0394Ct method","volume":"25","author":"Livak","year":"2001","journal-title":"Methods"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/0003-2697(64)90115-0","article-title":"Method for assay of intestinal disaccharidases","volume":"7","author":"Dahlqvist","year":"1964","journal-title":"Anal. Biochem."},{"key":"ref_23","unstructured":"Sun, X. (2007). Effect of Corn Quality and Enzyme Supplementation on Broiler Performance, Gastrointestinal Enzyme Activity, Nutrient Retention, Intestinal Mucin, and Jejunal Gene Expression, Virginia Tech."},{"key":"ref_24","unstructured":"SAS Institute (2008). SAS\u00ae User\u2019s Guide for Personal Computer, SAS Institute Inc."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1107","DOI":"10.1007\/s00726-012-1444-2","article-title":"Dietary requirements of \u201cnutritionally non-essential amino acids\u201d by animals and humans","volume":"44","author":"Wu","year":"2013","journal-title":"Amino Acids"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Ullrich, C., Langeheine, M., Brehm, R., Taube, V., Siebert, D., and Visscher, C. (2018). Influence of Reduced Protein Content in Complete Diets with a Consistent Arginine\u2013Lysine Ratio on Performance and Nitrogen Excretion in Broilers. Sustainability, 10.","DOI":"10.3390\/su10113827"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"477","DOI":"10.3382\/japr.2008-00105","article-title":"Impact of dietary amino acid and crude protein levels in broiler feeds on biological performance","volume":"18","author":"Pesti","year":"2009","journal-title":"J. Appl. Poult. Res."},{"key":"ref_28","first-page":"161","article-title":"Evaluating the effects of a novel phytogenic feed additive on performance of broilers fed a low or standard protein diet","volume":"82","author":"Pender","year":"2020","journal-title":"Poult. Sci. Ann. Meet."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Sadek, K., Ahmed, H., Ayoub, M., and Elsabagh, M. (2014). Evaluation of Digestarom and thyme as phytogenic feed additives for broiler chickens. Eur. Poult. Sci., 78.","DOI":"10.1399\/eps.2014.55"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1016\/j.anifeedsci.2011.03.020","article-title":"Assessment of a phytogenic feed additive effect on broiler growth performance, nutrient digestibility and caecal microflora composition","volume":"168","author":"Mountzouris","year":"2011","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"3443","DOI":"10.3382\/ps\/pey472","article-title":"Immune modulation, growth performance, and nutrient retention in broiler chickens fed a blend of phytogenic feed additives","volume":"98","author":"Pirgozliev","year":"2019","journal-title":"Poult. Sci."},{"key":"ref_32","first-page":"242","article-title":"Feedback control of AHR signalling regulates intestinal immunity","volume":"542","author":"Schiering","year":"2017","journal-title":"Nat. Cell Biol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.pharmthera.2018.02.012","article-title":"Modulation of CYP1A1 metabolism: From adverse health effects to chemoprevention and therapeutic options","volume":"187","author":"Mescher","year":"2018","journal-title":"Pharmacol. Ther."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3655","DOI":"10.1016\/j.psj.2020.03.058","article-title":"Effect of dietary Lactobacilli mixture on Listeria monocytogenes infection and virulence property in broilers","volume":"99","author":"Deng","year":"2020","journal-title":"Poult. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1080\/00071660701671336","article-title":"Nutrition and the immune system","volume":"48","author":"Klasing","year":"2007","journal-title":"Br. Poult. Sci."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"465","DOI":"10.17221\/138\/2019-CJAS","article-title":"Effect of tetramethylpyrazine on growth performance, Campylobacter jejuni carriage and endogenous antimicrobial peptides in rabbits","volume":"64","author":"Ding","year":"2019","journal-title":"Czech J. Anim. Sci."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"623","DOI":"10.5851\/kosfa.2019.e52","article-title":"Tetramethylpyrazine Protects Oxidative Stability and Gelation Property of Rabbit Myofibrillar Proteins","volume":"39","author":"Wang","year":"2019","journal-title":"Food Sci. Anim. Resour."}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/11\/3\/775\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:33:53Z","timestamp":1760160833000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/11\/3\/775"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,11]]},"references-count":37,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["ani11030775"],"URL":"https:\/\/doi.org\/10.3390\/ani11030775","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,11]]}}}