The percentage of 15 BF fatty acids and 16 IMF fatty acids were measured by gas chromatography in BF samples taken between the third and the fourth ribs and in 200 g of Longissimus dorsi samples, in the 157 BC animals (Additional file 3: Table S3).
Genome-wide transcriptional profiles of M. longissimus dorsi RNAs samples of 74 F2 animals of a pig resource population revealed 11,457 probe-sets representing genes expressed in the muscle.
Using Affymetrix Porcine Genome Arrays, 23,256 expression measurements were obtained from each M. longissimus dorsi RNA samples of these animals representing 11,265 unique genes according to the annotation reported by Tsai et al. [ 23].
Keeping this in mind, a possible explanation for the higher mRNA expression in the most cranial longissimus dorsi sample could be that because of its location, it has other energy demands and fibre type composition compared to more caudal parts of the muscle.
In a commercial pig slaughterhouse 4 samples were carefully collected from each of 50 cleaved pigs: a sample of the longissimus dorsi muscle near the 3rd or 4th rib, a sample of the longissimus dorsi muscle near the last rib, a longissimus dorsi sample near the 4th lumbar vertebra, and a sample of backfat.
Furthermore, samples of longissimus dorsi muscle were frozen at −30 °C to study the stability of FA during short- (1 month) and long-term (3 or 6 months) storage.
In short, approximately 150 mg samples of longissimus dorsi muscle tissue were completely saponified with 4.0 ml of 1.18 M KOH in ethanol at 90°C.
Samples of longissimus dorsi (LD) skeletal muscles were also taken from fetal lambs at 80, 100 and 120 days of gestation, new born lambs 2 3 days after birth (150 d) and lambs at 12 weeks of age (230 d).
Day 5 of WOF development was included in the subset and represented by samples of M. longissimus dorsi, treatment (iv) and M. psoas major, treatments (ii) and (iii).
