{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T21:57:43Z","timestamp":1787695063936,"version":"build-2784847793"},"reference-count":49,"publisher":"PeerJ","license":[{"start":{"date-parts":[[2018,12,18]],"date-time":"2018-12-18T00:00:00Z","timestamp":1545091200000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Educaci\u00f3n y Ciencia (Spain)","award":["AGL 2006-05937\/GAN"],"award-info":[{"award-number":["AGL 2006-05937\/GAN"]}]},{"name":"Ministerio de Educaci\u00f3n y Ciencia (Spain)","award":["AGL 2009-08916"],"award-info":[{"award-number":["AGL 2009-08916"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>In Iberian pig outdoor production, pigs are fed equilibrated diets until the final fattening period when grazing pigs consume mainly acorns from oak trees. Acorns are rich in energy but poor in crude protein where lysine is the first limiting amino acid (AA). Net portal appearance (NPA) is very useful to ascertain AA available for liver and peripheral tissues. The aim of this study was to determine NPA of AA in Iberian gilts fed with acorns and to ascertain if there was an effect of acorn feeding over time. Two sampling periods were carried out (after one day and after one week of acorn feeding) with six gilts (34 kg average BW) set up with three catheters: in carotid artery and portal vein for blood sampling, and ileal vein for a marker infusion to measure portal plasma flow (PPF). Pigs were fed at 2.5 \u00d7\u00a0ME for maintenance a standard diet in two meals, at 09:00 (0.25) and 15:00 h (the remaining 0.75). The day previous to first sampling, pig diet was replaced by 2.4 kg of acorn. A serial blood collection was done at \u22125 min, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5 and 6 h after feeding 0.25 of total daily acorn ration. Following identical protocol, one week later the second sampling was done. NPA of sum of essential AA (EAA) was poor. Although increased NPA of histidine (<jats:italic>P<\/jats:italic>\u00a0&lt;\u00a00.001), leucine, phenylalanine and valine (0.05\u00a0&lt;\u00a0<jats:italic>P<\/jats:italic>\u00a0&lt;\u00a00.08) was found after one week of acorn consumption, the sum of EAA did not change. Furthermore, fractional absorption (NPA\/AA intake) of EAA, non-essential AA (NEAA) and total AA was 97, 44 and 49% lower, respectively, at the beginning of eating acorn than a week later. Supplementation, with some of the EAA and NEAA to Iberian pigs during the grazing period would be beneficial to overcome the increased portal-drained viscera (PDV) utilization of AA observed in the present\u00a0study.<\/jats:p>","DOI":"10.7717\/peerj.6137","type":"journal-article","created":{"date-parts":[[2018,12,18]],"date-time":"2018-12-18T10:12:13Z","timestamp":1545127933000},"page":"e6137","source":"Crossref","is-referenced-by-count":6,"title":["Iberian pig adaptation to acorn consumption: II. Net portal appearance of amino acids"],"prefix":"10.7717","volume":"6","author":[{"given":"Manuel","family":"Lachica","sequence":"first","affiliation":[{"name":"Department of Physiology and Biochemistry of Animal Nutrition, Estaci\u00f3n Experimental del Zaid\u00edn, Consejo Superior de Investigaciones Cient\u00edficas, Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jose Miguel","family":"Rodr\u00edguez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"D\u00e9partment Sciences Agronomiques et Animales, Institut Polytechnique LaSalle Beauvais, Beauvais, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucrecia","family":"Gonz\u00e1lez-Valero","sequence":"additional","affiliation":[{"name":"Department of Physiology and Biochemistry of Animal Nutrition, Estaci\u00f3n Experimental del Zaid\u00edn, Consejo Superior de Investigaciones Cient\u00edficas, Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ignacio","family":"Fern\u00e1ndez-F\u00edgares","sequence":"additional","affiliation":[{"name":"Department of Physiology and Biochemistry of Animal Nutrition, Estaci\u00f3n Experimental del Zaid\u00edn, Consejo Superior de Investigaciones Cient\u00edficas, Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"4443","published-online":{"date-parts":[[2018,12,18]]},"reference":[{"key":"10.7717\/peerj.6137\/ref-1","doi-asserted-by":"publisher","first-page":"3771","DOI":"10.2527\/jas.2015-0077","article-title":"Postprandial portal fluxes of essential amino acids, volatile fatty acids, and urea-nitrogen in growing pigs fed a high-fiber diet supplemented with a multi-enzyme cocktail","volume":"94","author":"Agyekum","year":"2016","journal-title":"Journal of Animal Science"},{"key":"10.7717\/peerj.6137\/ref-2","volume-title":"Official methods of analysis","author":"Association\u00a0of Official Analytical Chemists\u00a0(AOAC)","year":"2000","edition":"17"},{"key":"10.7717\/peerj.6137\/ref-3","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1016\/S0167-4889(97)90005-7","article-title":"Arginine metabolism in rat enterocytes","volume":"1092","author":"Blachier","year":"1991","journal-title":"Biochimica et Biophysica Acta\/General Subjects"},{"key":"10.7717\/peerj.6137\/ref-4","doi-asserted-by":"publisher","first-page":"E1246\u2013E1257","DOI":"10.1152\/ajpendo.00150.2003","article-title":"Intestinal lysine metabolism is driven by the enteral availability of dietary lysine in piglets fed a bolus meal","volume":"285","author":"Bos","year":"2003","journal-title":"American Journal of Physiology, Endocrinology and Metabolism"},{"key":"10.7717\/peerj.6137\/ref-5","doi-asserted-by":"publisher","first-page":"E302\u2013E312","DOI":"10.1152\/ajpendo.00309.2002","article-title":"Somatotropin-induced protein anabolism in hindquarters and portal-drained viscera of growing pigs","volume":"284","author":"Bush","year":"2003","journal-title":"American Journal of Physiology, Endocrinology and Metabolism"},{"key":"10.7717\/peerj.6137\/ref-6","volume-title":"The Pico-Tag method. 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