Effect of corn silage supplementation on gene expression of antioxidant indicators in Braford steers

CASTAÑO LEDESMA, M.S.; CORIA, M.S.; BORSARELLI, CLAUDIO DARÍO; PALMA, G.A.

Congreso; Congreso Conjunto SAIB-SAMIGE; 2021

Oxidative processes in meat is responsible for quality deterioration including flavor, color and nutritive value. Antioxidant enzymes play a central role in the antioxidant defense system against oxidative damage in vivo, which include the endogenous enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). In addition there are proteins associated with nonenzymatic antioxidant: α-tocopherol transfer protein (α-TTP) and α-tocopherol associated protein (α-TAP), which would result in an indirect measure of the presence of non-enzymatic antioxidants. The oxidative stability of meat is also determined by the presence of antioxidants of dietary and may be modulated by nutritional factors. Argentine meat has been traditionally produced on pasture. However, to comply with some market requirements, grain finishing is becoming more common among producers. The aim of the present work was to evaluate the effect of corn silage supplementation on SOD, CAT, GPx, α-TTP y α-TAP gene expression. Briefly, 30 Braford steers were randomly divided into 2 experimental groups: 15 animals were fed ad libitum grass and supplemented with corn silage 120 days prior to slaughter, while the other 15 steers were fed ad libitum similar grass without corn supplement. Gene expression was evaluated in longissimus dorsi muscle samples. Messenger RNA was isolated by phenolchloroform method and reverse transcripted. Real-time PCRs were carried out with RPLP0 and 18SrRNA as reference genes. Pasture-fed steers muscles contained higher expression levels of CAT, SOD and GPx genes than the grain-fed group (p