{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T06:44:45Z","timestamp":1792133085687,"version":"4.4.0"},"reference-count":24,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"content-version":"vor","delay-in-days":260,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The objective of these experiments was to evaluate the effect of standardized ileal digestible (SID) Thr:Lys ratio on growth performance of late nursery, growing, and finishing pigs. Four experiments were conducted using corn-soybean meal-based diets with pigs allotted to 5 or 6 treatments in randomized complete block designs. In Exp. 1, 987 late nursery pigs (initially 11.8\u2009\u00b1\u20090.32\u2009kg) were used with 22 to 27 pigs per pen, 8 replications per treatment, and 5 SID Thr:Lys ratios from 53% to 68% of Lys. Increasing SID Thr:Lys ratio increased (linear, P\u2009\u2264\u20090.005) ADG and final BW. Average daily feed intake decreased then increased (quadratic, P\u2009&amp;lt;\u20090.001), therefore increasing then decreasing (quadratic, P\u2009&amp;lt;\u20090.001) G:F. In Exp. 2, 875 pigs (initially 43.4\u2009\u00b1\u20090.58\u2009kg) were used with 21 to 27 pigs per pen, 7 replications per treatment, and 5 SID Thr:Lys ratios from 53% to 68% of Lys. Increasing SID Thr:Lys ratio increased (linear, P\u2009\u2264\u20090.037) ADG, final BW, and G:F. Dose-response models developed using the data from Exp. 1 and 2 predicted a requirement estimate for ADG beyond the highest dose tested (68% SID Thr:Lys ratio), which led us to test a wider range of SID Thr:Lys ratios in Exp. 3 and 4. In Exp. 3, 684 pigs (initially 37.4\u2009\u00b1\u20091.36\u2009kg) were used with 9 or 10 pigs per pen, 12 replications per treatment, and 6 SID Thr:Lys ratios from 53% to 78% of Lys. Increasing SID Thr:Lys ratio increased then plateaued (quadratic, P\u2009\u2264\u20090.047) final BW, ADG, G:F and tended (quadratic, P\u2009=\u20090.093) to decrease then increase blood urea N (BUN). In Exp. 4, 662 pigs (initially 96.2\u2009\u00b1\u20091.04\u2009kg) were used with 8 to 10 pigs per pen, 11 or 12 replications per treatment, and 6 SID Thr:Lys ratios from 53% to 78% of Lys. Increasing SID Thr:Lys ratio tended to increase then decrease (quadratic, P\u2009\u2264\u20090.063) final BW, ADG, and G:F, with the greatest numeric response observed between 63% and 68% SID Thr:Lys ratio. Data from Exp. 3 and 4 were combined and used to fit dose response curves for ADG, G:F, and BUN. A quadratic polynomial (QP) model suggested that ADG was maximized at 68.6% SID Thr:Lys, while a similar fitting broken-line linear (BLL) model suggested no further improvement in ADG beyond 61.1% SID Thr:Lys. A BLL model suggested no further improvement in G:F beyond 59.2% SID Thr:Lys. A QP model suggested that BUN was minimized at 69.2% SID Thr:Lys. These data suggest that SID Thr:Lys requirements are similar for pigs from 37 to 70 and 96 to 120\u2009kg.<\/jats:p>","DOI":"10.1093\/tas\/txag142","type":"journal-article","created":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T19:26:36Z","timestamp":1789673196000},"source":"Crossref","is-referenced-by-count":0,"title":["Effects of standardized ileal digestible threonine to lysine ratio on growth performance of nursery, growing, and finishing pigs"],"prefix":"10.1093","volume":"10","author":[{"given":"Rafe Q","family":"Royall","sequence":"first","affiliation":[{"name":"Department of Animal Sciences and Industry, College of Agriculture, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mike D","family":"Tokach","sequence":"additional","affiliation":[{"name":"Department of Animal Sciences and Industry, College of Agriculture, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7268-4278","authenticated-orcid":false,"given":"Jason C","family":"Woodworth","sequence":"additional","affiliation":[{"name":"Department of Animal Sciences and Industry, College of Agriculture, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel M","family":"DeRouchey","sequence":"additional","affiliation":[{"name":"Department of Animal Sciences and Industry, College of Agriculture, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert D","family":"Goodband","sequence":"additional","affiliation":[{"name":"Department of Animal Sciences and Industry, College of Agriculture, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jordan T","family":"Gebhardt","sequence":"additional","affiliation":[{"name":"Department of Diagnostic Medicine\/Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, KS 66506-0201,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carine M","family":"Vier","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew","family":"Spindler","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weasley A","family":"Orlando","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis E Ochoa","family":"Zaragoza","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9329-3823","authenticated-orcid":false,"given":"Ning","family":"Lu","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wayne R","family":"Cast","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danielle F","family":"Wilson-Wells","sequence":"additional","affiliation":[{"name":"Genus PIC , Hendersonville, TN 37075,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia P","family":"Holen","sequence":"additional","affiliation":[{"name":"SVC Research , St. Peter, MN 56082,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alyssa M","family":"Betlach","sequence":"additional","affiliation":[{"name":"SVC Research , St. Peter, MN 56082,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,9,17]]},"reference":[{"key":"2026101601520979100_txag142-B1","doi-asserted-by":"publisher","first-page":"2061","DOI":"10.2527\/1994.7282061x","article-title":"Availability of amino acids for 10- to 20-kilogram pigs: lysine and threonine in soybean meal","volume":"72","author":"Adeola","year":"1994","journal-title":"J. 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