{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T17:28:34Z","timestamp":1781198914117,"version":"3.54.1"},"reference-count":41,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T00:00:00Z","timestamp":1775520000000},"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>An experiment was conducted in a commercial broiler farm to evaluate birds\u2019 growth performance, intestinal morphology (IM), and total blood carotenoid levels when adding different inclusion rates of microbial muramidase (MUR) to broilers\u2019 feed formula. A total of 336-day-old broilers from Ross 308 were assigned to three groups and were fed from day 1 to day 42. Treatment 1 (T1), the control treatment, was a basal corn soybean meal diet that followed Aviagen nutrient specifications; Treatment 2 (T2) was the control treatment + 350 g MUR per ton of feed; Treatment 3 (T3) was the control treatment + 450 g MUR per ton of feed. Body weight gain (BWG), feed intake (FI), the feed conversion ratio (FCR), carotenoid levels (CLs), and IM from samples of the duodenum, jejunum, and ileum were evaluated on day 42. MUR significantly outperformed the control diet in terms of body weight (BW), resulting in BWs of 2513 g (p = 0.005) and 2463 g with T3 and T2, respectively, versus 2377 g with T1. Daily weight gain (DWG) was 58.77 g and 57.58 g in T3 and T2 (p = 0.0004), respectively, versus 55.54 g in T1. The Daily Feed Intake (DFI) on day 42 was higher in T3 compared to T1 (98.90 g p &lt; 0.0001 versus 97.72 g). The morphology results show higher effects in the duodenum with T3 versus T2 and T1. In addition, the results were significantly higher in the jejunum when using T2 and T3 compared to T1. Goblet cells were not influenced by MUR use in the diets. The broilers\u2019 blood carotenoid levels were significantly higher in T3 (1.75 mg\/L p = 0.0026) compared to T1 (1.02 mg\/L). These results shed light on broilers\u2019 performance, intestinal health, and nutrient availability when using MUR at different inclusion rates in broiler feed for broilers raised under near-commercial conditions.<\/jats:p>","DOI":"10.3390\/ani16071123","type":"journal-article","created":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T09:40:31Z","timestamp":1775554831000},"page":"1123","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimizing Broiler Performance and Intestinal Morphology and Increasing Nutritional Availability via Microbial Muramidase Supplementation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-5155-149X","authenticated-orcid":false,"given":"Akram El","family":"Kadi","sequence":"first","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Radmila","family":"Markovi\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dejan","family":"Peri\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9918-3358","authenticated-orcid":false,"given":"Sladjan","family":"Ne\u0161i\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4799-9416","authenticated-orcid":false,"given":"Nata\u0161a","family":"Glamo\u010dlija","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aur\u00e9lia A.","family":"S\u00e9on Simon","sequence":"additional","affiliation":[{"name":"Research Center for Animal Nutrition & Health\u2014DSM Nutritional Products France, 1 Boulevard d\u2019Alsace, 68128 Village Neuf, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dragan","family":"\u0160efer","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1093\/ps\/81.1.41","article-title":"Interaction of dietary vitamin E with Eimeria maxima infections in chickens","volume":"81","author":"Allen","year":"2002","journal-title":"Poult. 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