title: Gene expression, serum amino acid levels, and growth performance of pigs fed dietary leucine and lysine at different ratios.
abstract: We examined 96 pigs (28.1 ± 0.83 kg) to analyze the effect of Leu:Lys ratios on expression of the cationic amino acid transporters b(0,+) and CAT-1 in the jejunum and liver as well as myosin expression in 2 muscles to estimate the optimum standardized ileal digestible (SID) Leu:Lys ratio for growth rate and efficiency. A wheat-and wheat bran-based diets were formulated to meet the requirements of SID amino acids other than Leu (0.70%) and Lys (0.80%). L-Leu was added to the basal diet in 5 SID Leu:Lys ratios (88, 100, 120, 140, and 160% in diets 1-5). Tissue samples were collected from 8 pigs with ratios of 88, 120, and 160%. Relative expression of b(0,+), CAT-1, and myosin was analyzed. b(0,+) expression in the jejunum was higher but lower in the liver of pigs with the 120% ratio compared to those with the 88 or 160% ratio; myosin expression in longissimus dorsi was also higher in pigs with the 120% ratio (P < 0.05). CAT-1 was lower in the jejunum and longissimus dorsi of pigs with 120 or 160% ratios than in pigs with 88%. Serum concentration of nearly all amino acids decreased with excess dietary Leu (P < 0.05). The SID Leu:Lys of 104 and 109% optimized average daily gain and feed conversion ratio, respectively. Thus, the dietary Leu:Lys ratio affects the expression of genes coding for amino acid transporters and myosin, the availability of Lys, and the growth rate and efficiency in pigs.
authors: Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, BC, México.
authors: H
authors: H
authors: García
authors: Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, BC, México.
authors: A
authors: A
authors: Morales
authors: Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, BC, México.
authors: A
authors: A
authors: Araiza
authors: Evonik Industries AG, Nutrition Research, Hanau, Germany.
authors: J K
authors: JK
authors: Htoo
authors: Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, BC, México miguel_cervantes@uabc.edu.mx.
authors: M
authors: M
authors: Cervantes
mesh_terms: D000818:Animals; D027201:Cationic Amino Acid Transporter 1 / Q000097:blood / Q000235:genetics; D004032:Diet / Q000662:veterinary; D015870:Gene Expression; D007082:Ileum / Q000187:drug effects / Q000378:metabolism; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism; D007930:Leucine / Q000008:administration & dosage* / Q000097:blood*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008239:Lysine / Q000008:administration & dosage* / Q000097:blood*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D009218:Myosins / Q000235:genetics / Q000378:metabolism; D013552:Swine / Q000235:genetics / Q000254:growth & development*; D015430:Weight Gain
chemical_list: D027201:Cationic Amino Acid Transporter 1; D009218:Myosins; D007930:Leucine; D008239:Lysine