Slaughter surveys and sampling
At the completion of the feeding experiment, all pigswere electrically
stunned, exsanguinated, dehaired, eviscerated, and split down the
midline according to standard commercial procedures. Hot carcass
weight was individually recorded and used to calculate dressing percentage.
Midline backfat depth opposite the first rib, last rib, and last
lumbar vertebrae was recorded, and m. longissimus dorsi (LM) area
(LA) was measured at the 10th rib of the left side carcass. Then, LM
from the left side carcass was collected and refrigerated at 2–4 °C for
meat quality data collection. Within 20 min of slaughter, about 150 g
of LM sample from the right side of the carcass was taken anterior to
the 10th rib and frozen at−20 °C until lyophilization for muscle chemical
analysis. Meanwhile, an approximately 1-cm-thick LM sample was
taken posterior to the 10th rib and was frozen in liquid nitrogen until
used for RNA extraction, as well as enzyme activity, glycolytic potential,
malonaldehyde (MDA) and myoglobin content measurement.