Effect of selection for reduced residual feed intake on composition and quality of fresh pork

Selection for improved growth efficiency has the potential to alter meat composition and meat quality. The objective of this study was to determine the extent to which selection for reduced residual feed intake (RFI) affects pork composition and quality. In order to achieve this, pork composition and meat quality traits were compared between a line selected for reduced RFI over five generations (select) and a randomly selected control line (control). Residual correlations between RFI and pork composition and quality traits were also evaluated. In the evaluated group of Yorkshire gilts (select = 80, control = 89), gilts from the select line had 0.052 kg lower RFI per day. Gilts were harvested at ~114 kg, and the boneless loins were collected at 24 h postmortem. Back fat and loin eye depth were collected off the midline at the last rib region using the Fat-O-Meater. Quality attributes were measured at 2 d postmortem. Drip loss and water holding capacity were measured in duplicate. Hunter L, a, and b values were measured in triplicate on two chops. Quality scores were assigned by a 3 member panel. Intramuscular lipid and moisture content were determined. Desmin degradation was measured at 2 and 7 d postmortem. Purge, cook loss, sensory traits, and star probe texture were measured at 7-10 d postmortem on cooked chops.