Expression of cationic amino acid transporters, carcass traits, and performance of growing pigs fed low-protein amino acid-supplemented versus high protein diets

  • Author(s) / Creator(s)
  • Free amino acids (AA) appear to be absorbed faster than protein-bound AA (PB-AA). We conducted an experiment to assess the effect of feeding pigs with a partially free (F-AA) or totally PB-AA diet on expression of selected genes and performance of pigs. The expression of cationic AA transporters b0,+ and CAT-1 in intestinal mucosa, liver, and longissimus (LM) and semitendinosus (SM) muscles, as well as that of myosin in LM and SM, was analyzed. Twelve pigs (31.7 ± 2.7 kg) were used. The F-AA diet was based on wheat, supplemented with 0.59% L-Lys, 0.33% L-Thr, and 0.10% DL-Met. The PB-AA diet was formulated with wheat-soybean meal. Average daily feed intake was 1.53 kg per pig. The expression of b0,+ and CAT-1 was analyzed in jejunal and ileal mucosa, liver, LM, and SM; myosin expression was also analyzed in both muscles. Pigs fed the PB-AA diet tended to have higher weight gain and feed efficiency (P < 0.10), and had thinner back fat (P = 0.02). The expression of b0,+ was higher (P < 0.01) in jejunum but lower (P < 0.01) in the liver of pigs fed the F-AA diet; CAT-1 tended to be lower in liver but higher in LM of PB-AA pigs. Myosin expression was not affected. Intestinal AA absorption was faster in pigs fed the F-AA diet, but AA uptake by the liver seemed to be faster in pigs fed the PB-AA. Performance and expression of AA transporters and myosin suggest that the dietary content of free or protein-bound AA does not affect their availability for protein synthesis in pigs.

  • Date created
    2013
  • Subjects / Keywords
  • Type of Item
    Article (Published)
  • DOI
    https://doi.org/10.7939/R3D795Q59
  • License
    Attribution-NonCommerical-ShareALike 4.0 International
  • Language
  • Citation for previous publication
    • Morales, A., Grageola, F., García, H., Araiza, A., Zijlstra, R. T., & Cervantes, M. (2013). Expression of cationic amino acid transporters, carcass traits, and performance of growing pigs fed low-protein amino acid-supplemented versus high protein diets. Genetics and Molecular Research, 12(4), 4712-4722. http://dx.doi.org/10.4238/2013.October.18.9
  • Link to related item
    http://dx.doi.org/10.4238/2013.October.18.9