molecular genome scan analysis to identify chromosomal regions influencing economic traits in the pig. II. Meat and muscle composition

Molecular genetic markers can be used to identify chromosomal regions that contain quantitative trait loci (QTL) that control meat quality and muscle composition traits in farm animals. To study this in pigs, a resource family was generated from a cross between two Berkshire grand sires and nine Yorkshire grand dams. A total of 525 F₂ progeny from 65 matings of F₁ parents were produced. Phenotypic data on 28 meat quality traits (drip loss, water holding capacity, firmness, color, marbling, percentage cholesterol, ultimate pH, fiber type, and several sensory panel and cooking traits) were collected on the F₂ animals. Animals were genotyped for 125 microsatellite markers covering the entire genome. Least squares regression interval mapping was used for QTL detection. Significance thresholds were determined by permutation tests. A total of 60 QTL were detected at the 5% chromosome level for meat quality traits, on Chrs 1, 2, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 17, 18, and X, of which 9 and 1 QTL were significant at the 5% and 1% genome-wise levels (on Chrs 1, 5, 12, 15, and 17), respectively.