Relationship between marbling group and major muscle contribution to beef carcass mass

摘要: Left sides from 18 beef carcasses (9 steers and 9 heifers) were divided equally among three marbling groups (low = traces or slight; intermediate small modest; high slightly abundant) evaluated to determine the relationship between longissimus composition percentage each major muscle contributes weight of carcass. The adductor (A), biceps femoris (BF), deep pectoral @P), gluteal group (GL), infraspinatus 0, (L), psoas rectus abdominis (RA), (RF), semimembranosus (SM), semitendinosus (ST), serratus ventralis (SV), spinalis (SP), supraspinatus (SU) triceps brachii (TB) removed, trimmed external fat weighed. Muscle weights expressed as a hot carcass weight: A .76%; BF 3.30%; DP 1.89%; GL 1.81%; I 1.10%; L 3.35%; PM .95%; RA 1.12%; RF .94%; SM 2.35%; ST 1.14%; SV 2.26%; SP .82%; SU .69% TB 1.83%. heavier (P < .05) in steer than heifer carcasses. No other sisnificant sex effects noted. Percentage tended decrease with increasing level; however, linear regression relative on level was significant for BP, DP, PM, SM, TB. Using score yield grade factors predict individual muscles resulted R2 values greater .4 7 15 evaluated. Results froin this study indicated that composed increased; effect only 6 tested. Prediction equations suggested factor affecting contributed overall fatness (marbling grade).