title: Effect of Season, Transport Length, Deck Location, and Lairage Length on Pork Quality and Blood Cortisol Concentrations of Market Hogs.
abstract: The objective of this study was to investigate the effects of seasonal environment, transport conditions, and time in lairage on pork quality and serum cortisol concentrations. Market hogs were slaughtered during winter (n = 535), spring (n = 645), summer (n = 644), and fall (n = 488). Within season, hogs were randomly assigned to treatments in a 2 × 2 × 2 factorial arrangement, with 2 deck locations (top vs. bottom) and 2 transport and lairage durations (3 h vs. 6 h). Blood samples were collected at exsanguination for analysis of cortisol concentration. Loins were collected at 24 h postmortem for pork quality assessment. Season and deck did not have a main effect on cortisol concentrations or pork quality. Hogs transported 6 h had increased cortisol concentrations (103.0 vs. 95.5 ng/mL; P < 0.001) and decreased L* (52.49 vs. 52.69; P = 0.09), b* (6.28 vs. 6.36; P = 0.03), and hue angle (20.70 vs. 20.95; P = 0.03) compared to hogs transported 3 h. Hogs subjected to 6 h of lairage had increased 24-h pH (5.69 vs. 5.66; P = 0.005), a* (16.64 vs. 16.48; P < 0.0001), b* (6.42 vs. 6.22; P < 0.0001), saturation (17.85 vs. 17.64; P < 0.0001), and hue angle (21.01 vs. 20.65; P = 0.002) and decreased L* (52.49 vs. 52.69; P = 0.07) when compared to hogs subjected to 3 h of lairage.
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA. david.newman@ndsu.edu.
authors.forename: David
authors.initials: D
authors.lastname: Newman
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA. jennifer.m.young@ndsu.edu.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Young
authors.affiliation: Department of Animal Sciences, University of Florida, Gainseville, FL 32611, USA. chadcarr@ufl.edu.
authors.forename: Chad
authors.initials: C
authors.lastname: Carr
authors.affiliation: Farmland Foods, Wichita, KS 67213, USA. mryan@farmland.com.
authors.forename: Matt
authors.initials: M
authors.lastname: Ryan
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA. eric.p.berg@ndsu.edu.
authors.forename: Eric
authors.initials: E
authors.lastname: Berg
keywords: lairage; pork quality; season; swine; transport; welfare