0767 Vitamin C supplement increased intramuscular adipose tissues but not affect myogenic development of Hanwoo steers

Abstract

Vitamin C (VC) supplements have been used for enhancing marbling fat in high-quality beef cattle. However, mode of action of vitamin C was not clearly studied for long time. The aim of this experiment was to determine the effect of additional saturated parm-oil coated VC supplement compare to a control diet (saturated parm-oil only) on the level of adipogenic and myogenic gene expressions at liver (LV), subcutaneous adipose tissue (SC), perirenal adipose tissue (PR), and longissimus dorsi muscle (LD). A 2 × 4 factorial arrangement (control, VC, and LV, SC, PR, and LD tissues) was used to feed 10 Hanwoo steers. Two steers were fed in same pen and 5 pens were used for treatment. Tissues were collected within 10 min of harvest for analysis of PPARγ, SCD, GLUT4, MHC1, MHC2X, and GPR43 mRNA abundance. Real-time RT-PCR was used to measure the quantity of respective mRNA relative to a ribosomal protein subunit 9 (RPS9) mRNA. Data were analyzed as a completely randomized design using the MIXED model. Difference between the control and treatments were determined using the LSD procedure. Overall ADG did not differ between VC supplement and the control (P > 0.05). Marbling score was greater in the VC treatment than in the control (P < 0.05). Lipid percentage tended to greater (P = 0.084) in the VC treatment but share force tended to be lower in the VC treatment (P = 0.068). Real-time quantitative PCR revealed that the mRNA content of SCD in PR from VC supplement cattle increased (P < 0.05) compared with the control. There was no mRNA effect at MUS in cattle. However, mRNA level of GLUT4 and GPR43 were increased at LV tissues in VC-treated cattle (P > 0.05). These data indicated that VC supplement increased relative mRNA level of GLUT4 and SCD in SC and LV tissue but not affect myogenic gene expression on final fattening periods of Hanwoo steers.