The efficiency of electrical stimulation to counteract the negative effects of β-agonists on meat tenderness of feedlot cattle

• Published in: Meat science Vol. 86; no. 3; pp. 699 - 705
• Main Authors: Hope-Jones, M., Strydom, P.E., Frylinck, L., Webb, E.C.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2010; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: Adrenergic beta-Agonists - adverse effects; Animal Feed; Animals; beef; beta-adrenergic agonists; Biological and medical sciences; Calcium-Binding Proteins - metabolism; calpain; Calpain - metabolism; Calpains; calpastatin; Cattle; Electric Stimulation; Electrical stimulation; electrical treatment; enzyme activity; feedlots; Food industries; Food Technology; Fundamental and applied biological sciences. Psychology; loins; Male; Meat - analysis; meat aging; Meat and meat product industries; meat carcasses; Meat tenderness; Muscle Proteins - metabolism; Muscle, Skeletal - drug effects; Muscle, Skeletal - metabolism; muscles; Myofibrils - drug effects; Rigor Mortis; sarcomeres; Sarcomeres - drug effects; shear stress; slaughter; steers; Stress, Mechanical; Trimethylsilyl Compounds - adverse effects; Zilpaterol; Electrical stimulation; Calpains; Zilpaterol; Meat tenderness; Efficiency; Tenderness; Meat product; Meat
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/j.meatsci.2010.06.008

Beta agonists used as growth enhancers are known to affect the aging potential of beef muscle negatively. On the other hand, procedures like electrical stimulation could accelerate rigor and the aging process. In this study, 20 out of 40 young steers received no beta agonist (C), the remaining twenty steers received a beta agonist (zilpaterol hydrochloride) (Z) for the 30 days prior to slaughter followed by 4 days withdrawal. After slaughter carcasses were split, the left side electrically stimulated (ES) and the right side not stimulated (NES). Samples were aged for 3 or 14 days post mortem. Parameters included Warner Bratzler shear force (WBSF), myofibril filament length (MFL), sarcomere length and calpastatin and calpain enzyme activity. Zilpaterol resulted in increased ( P < 0.001) WBSF mainly due to an increased ( P < 0.001) calpastatin activity. ES improved tenderness ( P < 0.001) in general by early onset of rigor triggering the activity of calpains. ES also reduced the calpastatin activity ( P < 0.001), which partially countered the effect of high calpastatin activity on the aging potential of Z loins. ES can therefore be implemented to improve meat tenderness in zilpaterol supplemented steers, although steers without zilpaterol will still have an advantage in final tenderness.