Table 3 Muscular characteristics of LT and RA muscles from Charolais heifers (second study)
From: Specific fibre composition and metabolism of the rectus abdominis muscle of bovine Charolais cattle
Second study (153 Charolais heifers) | |||
|---|---|---|---|
RA muscle | LT muscle | Significance: | |
Number of heifers | 153 | 153 | |
Fibre cross-sectional area (histochemical analysis) | |||
Mean | 3379 (100) | 2639 (64) | p < 0.001 |
Myosin heavy chain (MyHC) isoforms (SDS-PAGE electrophoresis) | |||
MyHC I proportion (%) | 31.6 (0.5) | 22.3 (0.6) | p < 0.001 |
MyHC IIa proportion (%) | 36.9 (0.7) | 47.4 (1.2) | p < 0.001 |
MyHC IIx proportion (%) | 31.1 (0.7) | 29.7 (1.4) | p > 0.10 |
Metabolic type of muscles (enzyme activity determination) | |||
ICDH activity (μmol.min.-1.g-1) | 1.46 (0.04) | 1.25 (0.04) | p < 0.001 |
LDH activity (μmol.min.-1.g-1) | 555 (6) | 835 (13) | p < 0.001 |
COX activity (μmol.min.-1.g-1) | 16.6 (0.4) | 10.4 (0.3) | p < 0.001 |
LDH/ICDH ratio | 407 (57) | 856 (108) | p < 0.001 |