{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:03:15Z","timestamp":1760148195118,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,4,5]],"date-time":"2023-04-05T00:00:00Z","timestamp":1680652800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Ministry of Science and Innovation","award":["AGL 2006-05937\/GAN","AGL 2009-08916\/GAN"],"award-info":[{"award-number":["AGL 2006-05937\/GAN","AGL 2009-08916\/GAN"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Iberian pigs have low rates of muscle protein deposition compared with modern breeds. Differences in net portal appearance (NPA) of amino acids (AA) might partially explain that. NPA of AA was measured in six Iberian and six Landrace gilts (28 kg) fitted with catheters in portal and mesenteric (para-aminohippuric acid infusion) veins, and carotid artery. Blood samples from porta and artery were simultaneously taken at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, and 6-h after feeding two isoenergetic diets (14\u201314.5 MJ metabolizable energy\/kg dry matter) with different crude protein (145 (LCP) and 187 (HCP) g\/kg dry matter) content. NPA of essential AA (EAA) and non-essential AA (NEAA) was lower (p &lt; 0.05) in Iberian than Landrace pigs, and in LCP than HCP diet. Fractional absorption (NPA\/AA intake) of EAA, NEAA, and total AA was, respectively, 36, 49, and 44% lower in LCP than HCP diet in Iberian pigs; and 8, 2, and 4% greater in Landrace pigs. Fractional absorption of EAA, NEAA, and total AA was 42, 68, and 60% lower in Iberian than Landrace pigs fed LPC diet; and 1, 36, and 26% when fed the HCP diet. NPA of AA may partially explain the low growth rate of Iberian pigs.<\/jats:p>","DOI":"10.3390\/ani13071263","type":"journal-article","created":{"date-parts":[[2023,4,6]],"date-time":"2023-04-06T01:10:27Z","timestamp":1680743427000},"page":"1263","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Net Portal Appearance of Amino Acids in Iberian and Landrace Pigs Fed Different Protein Content in the Diet"],"prefix":"10.3390","volume":"13","author":[{"given":"Manuel","family":"Lachica","sequence":"first","affiliation":[{"name":"Department of Nutrition and Sustainable Animal Production, Estaci\u00f3n Experimental del Zaid\u00edn, CSIC, San Miguel 101, Armillla, 18100 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9 Miguel","family":"Rodr\u00edguez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"D\u00e9partment Sciences Agronomiques et Animales, Institut Polytechnique LaSalle Beauvais-Esitpa, 19 Rue Pierre Waguet, BP 30313, 60026 Beauvais, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lucrecia","family":"Gonz\u00e1lez-Valero","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Sustainable Animal Production, Estaci\u00f3n Experimental del Zaid\u00edn, CSIC, San Miguel 101, Armillla, 18100 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ignacio","family":"Fern\u00e1ndez-F\u00edgares","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Sustainable Animal Production, Estaci\u00f3n Experimental del Zaid\u00edn, CSIC, San Miguel 101, Armillla, 18100 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.livsci.2008.05.006","article-title":"Foraging of Iberian fattening pigs grazing natural pasture in the dehesa","volume":"120","year":"2009","journal-title":"Livest. 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