{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T04:48:55Z","timestamp":1772945335362,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T00:00:00Z","timestamp":1755734400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key Research and Development Program of Zhejiang Province","award":["2024C02004"],"award-info":[{"award-number":["2024C02004"]}]},{"name":"Key Research and Development Program of Zhejiang Province","award":["CARS-35"],"award-info":[{"award-number":["CARS-35"]}]},{"name":"China Agriculture Research System","award":["2024C02004"],"award-info":[{"award-number":["2024C02004"]}]},{"name":"China Agriculture Research System","award":["CARS-35"],"award-info":[{"award-number":["CARS-35"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The objective of this study was to evaluate the effect of reducing dietary protein levels on barrows during the late fattening period. Fifty Duroc \u00d7 Landrace \u00d7 Yorkshire barrows with body weights averaging 76.30 \u00b1 6.57 kg were randomly divided into normal protein (NP) and low protein (LP) groups. The feeding experiment lasted for 55 days. Dietary crude protein (CP) contents were 13.5% in the NP and 11.5% in the LP during days 1\u201328 and 12.5% and 10.5% during days 29\u201355, respectively. Results showed that compared with the NP, the LP increased the average daily gain (ADG) of barrows during days 29\u201355 (p &lt; 0.05); enhanced the digestibility of nutrients, including dry matter (p &lt; 0.01), CP (p &lt; 0.01), calcium (p &lt; 0.01), and phosphorus (p &lt; 0.05); and decreased serum blood urea nitrogen (p &lt; 0.01), total cholesterol (p &lt; 0.05), and free fatty acids (p &lt; 0.05). Lowering dietary CP increased fecal Lactobacillus abundance (p &lt; 0.01); reduced concentrations of fecal ammonia nitrogen, histamine, butylamine, putrescine, 1,2-heptaenediamine, p-cresol, and indole-3-acetic acid (p &lt; 0.01); and had no negative effects on meat quality (p &gt; 0.05). These results suggested that reducing dietary CP by 2% could improve growth, promote efficient nutrient utilization, increase beneficial fecal microbiota abundance, and reduce the emission of fecal malodorous compounds in late-fattening barrows.<\/jats:p>","DOI":"10.3390\/ani15162465","type":"journal-article","created":{"date-parts":[[2025,8,22]],"date-time":"2025-08-22T07:41:45Z","timestamp":1755848505000},"page":"2465","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Reduced Dietary Protein Levels Improved Growth Performance, Promoted Efficient Nutrient Utilization, Increased Fecal Lactobacillus, and Reduced Fecal Malodorous Compounds in Late-Fattening Barrows"],"prefix":"10.3390","volume":"15","author":[{"given":"Xin","family":"Tao","sequence":"first","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Wu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shujie","family":"Liu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qianqian","family":"Ma","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoming","family":"Men","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongming","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziwei","family":"Xu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4679-0111","authenticated-orcid":false,"given":"Bo","family":"Deng","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wang, Y., Zhou, J., Wang, G., Cai, S., Zeng, X., and Qiao, S. 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