{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:19:08Z","timestamp":1785428348831,"version":"3.56.0"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,27]],"date-time":"2023-12-27T00:00:00Z","timestamp":1703635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Precise and Intelligent Feeding with Environmental Control System of Pig Production in Sichuan","award":["2021ZDZX0011"],"award-info":[{"award-number":["2021ZDZX0011"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This experiment was conducted in weaned piglets to determine the effects of exogenous protease to low soybean meal (SBM) diets on growth performance, diarrhea rate, nutrient digestibility, and intestinal morphology. Seventy-two Duroc \u00d7 Landrace \u00d7 Yorkshire weaned barrows (21-day-old, 5.88 \u00b1 0.95 kg) were randomly divided into four treatments with six replicates in each following a 2 \u00d7 2 factorial arrangement of SBM levels (0 to 14 d, 9%, 7.5%; 15 to 42 d, 20%, 18.5%) and protease (0 or 150 mg\/kg) for a 42-day trial. Fecal samples were collected on days 11 to 14 and 38 to 42 of the experiment, and serum, intestinal tissue, and chyme samples were taken at the end of the experiments. Adding protease in low SBM diets had a significant increase in ADG (p &lt; 0.05) and a decrease in F\/G (p &lt; 0.05). Protease significantly reduced the diarrhea rate (p &lt; 0.05). Low SBM level decreased the apparent total tract digestibility (ATTD) of crude protein (CP) and ash (p &lt; 0.05) but increased the ATTD of dry matter (DM), ash, organic matter (OM), and CP after the addition of protease (p &lt; 0.05). The apparent ileal digestibility (AID) of aspartic acid (Asp), threonine (Thr), serine (Ser), alanine (Ala), lysine (Lys), and total amino acids (AAs) were significantly increased by protease supplementation (p &lt; 0.05). Both the SBM-reduced and protease-added diets lead to lower albumin (ALB), albumin\/globulin (A\/G), and urea nitrogen (UREA) (p &lt; 0.05), but greater globulin (GLOB) with low SBM diets (p &lt; 0.05). The SBM-reduced and protease-added diets decreased the duodenum pH, respectively (p &lt; 0.05). The protease increased the villus:crypt (V:C) in the duodenum and ileum, and ileal villus length (p &lt; 0.05). In conclusion, the dietary supplementation of 150 mg\/kg protease improved the intestinal health and performance of the weaned piglets and reversed the negative effect of a 1.5% SBM reduction in nutrient utilization, intestinal pH, and intestinal morphological parameters of weaned piglets.<\/jats:p>","DOI":"10.3390\/ani14010101","type":"journal-article","created":{"date-parts":[[2023,12,27]],"date-time":"2023-12-27T10:23:54Z","timestamp":1703672634000},"page":"101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Effects of Protease in Soybean Meal-Reduced Diets on Growth Performance, Nutrient Digestibility, and Intestinal Health of Weaned Piglets"],"prefix":"10.3390","volume":"14","author":[{"given":"Junhong","family":"Zhang","sequence":"first","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunxiang","family":"Zhou","sequence":"additional","affiliation":[{"name":"Medical School, Huanghe Science and Technology University, Zhengzhou 450009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Honglei","family":"Zou","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Li","sequence":"additional","affiliation":[{"name":"Sichuan Tequ Agriculture and Animal Husbandry Technology Group Co., Ltd., Chengdu 610207, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6605-6742","authenticated-orcid":false,"given":"Bing","family":"Yu","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1963-9766","authenticated-orcid":false,"given":"Jun","family":"He","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Zheng","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6292-7747","authenticated-orcid":false,"given":"Xiangbing","family":"Mao","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7476-3914","authenticated-orcid":false,"given":"Hui","family":"Yan","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junqiu","family":"Luo","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuheng","family":"Luo","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinyong","family":"Chen","sequence":"additional","affiliation":[{"name":"Medical School, Huanghe Science and Technology University, Zhengzhou 450009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Yu","sequence":"additional","affiliation":[{"name":"Key Laboratory for Animal Disease-Resistance Nutrition of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, China"},{"name":"Sichuan Tequ Agriculture and Animal Husbandry Technology Group Co., Ltd., Chengdu 610207, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"576","DOI":"10.1007\/s11694-022-01628-3","article-title":"Monitoring of critical parameters in thermophilic solid-state fermentation process of soybean meal using NIR spectroscopy and chemometrics","volume":"17","author":"Dai","year":"2023","journal-title":"J. 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