Resumo
The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.(AU)
Assuntos
Animais , Bovinos , Glicerol/administração & dosagem , Estresse Fisiológico , Estresse Oxidativo , Suplementos Nutricionais , Biomarcadores , Carne Vermelha/análise , Abate de AnimaisResumo
The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.