Using phenotypic and genotypic big data to investigate the effect of muscle fiber characteristics on meat quality and eating quality traits in pigs.

Determining genetic correlations (GCs) between phenotypes that can be replicated across breeds or generations is important for animal breeding. A comprehensive and objective evaluation of this is dependent on enough variations in the studied phenotypes. To this end, we constructed a worldwide distributed eight-breeds crossbreed mosaic pig population and estimated the genetic and phenotypic correlations of muscle fiber characteristics (MFCs) with meat quality and eating quality traits using F6 and F7 generations (∼590 samples/generation) of this population. The GCs of the density of type IIA fibers and type IIB fibers with the loin-eye area, a*, color score, firmness score, and those of the proportions of the two fiber types with pH24h and b* were moderate to high (|rg| ≥ 0.3) in both populations. We also obtained moderate to high GCs of mean fiber density with five sensory quality traits. Our results provide an important reference for improving meat quality through the genetic regulation of MFCs.