This study took place with two groups of 25 and 30 Charolais
young bulls and two groups of 21 and 19 Charolais
steers (castrated at 3 months of age) slaughtered in two
different years (years 1 and 2) from the French MUGENE
programme (Genanimal-APISGENE 2005-2009). All animals
proceed from the same experimental farm
(Bourges) and were progeny of the same seed stock sample.
The young bulls were reared in the same experimental
farm (Bourges) and slaughtered at 17 months on
average. The steers were reared in the experimental farm
“Le Pin au Haras” and slaughtered at 30 months on average.
All animals were slaughtered in the same conditions
and without any electrical stimulation at the INRA experimental
slaughterhouse in compliance with current
INRA ethical guidelines for animal welfare [22]. Muscle
samples from the Longissimus thoracis were excised
within 15 minutes after slaughter. Muscle samples were
immediately frozen in liquid nitrogen and stored at -80°C
until RNA extraction.