Effects of supplemental manganese on performance of growing-finishing pigs and pork quality during retail display1

• Published in: Journal of animal science 2007-04, Vol.85 (4), p.1046-1053
• Main Authors: Sawyer, J. T., Tittor, A. W., Apple, J. K., Morgan, J. B., Maxwell, C. V., Rakes, L. K., Fakler, T. M.
• Format: Article
• Language: English
• Subjects: Effects; Manganese compounds; Pork; Quality; Studies; Zoology
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jas.2006-262

Crossbred barrows and gilts (n = 168) were used to test the effects of supplemental Mn during the growing-finishing period on performance, pork carcass characteristics, and pork quality during 7 d of retail display. Pigs were blocked by BW and allotted within blocks to pens (5 pigs/pen in blocks 1, 2, 5, and 6, and 4 pigs/pen in blocks 3 and 4). A total of 36 pens was randomly assigned to 1 of 6 dietary treatments, where the basal diets were formulated with (PC) or without (NC) Mn in the mineral premix, and supplemented with 0 or 350 ppm (as-fed basis) of Mn from MnSO^sub 4^ or a Mn-AA complex (AvMn). Pigs were slaughtered at a commercial pork packing plant when the lightest block of pigs averaged 113.6 kg. During fabrication, boneless pork loins were collected and transported to Oklahoma State University, where 2.5-cm-thick LM chops were packaged in a modified atmosphere (80% O2 and 20% CO2) and subsequently placed in display cases (2 to 4°C) under continuous fluorescent lighting (1,600 lx) for 7 d. Pig performance was not (P ≥ 0.44) affected by supplemental Mn; however, during the grower-II phase, pigs fed the basal diets including Mn consumed less (P < 0.02) feed and tended to be more efficient (P < 0.09) than pigs fed the basal diets devoid of Mn. Throughout the entire feeding trial, neither dietary nor supplemental Mn altered (P ≥ 0.22) ADG, ADFI, or G:F. Chops from pigs fed the diets supplemented with MnSO^sub 4^ received greater (P ≤ 0.05) lean color scores and had a redder (greater a* and hue angle values), more vivid color than chops from pigs fed the diets supplemented with AvMn. Additionally, LM chops from pigs fed the PC diets supplemented with MnSO^sub 4^ were darker (lower L* values; P < 0.05) than chops from pigs fed the NC diets or PC diets supplemented with 0 or 350 ppm of AvMn. Even though discoloration scores were similar during the first 4 d of display, chops from pigs fed the PC diets supplemented with MnSO^sub 4^ were less (P < 0.05) discolored on d 6 and 7 of retail display than chops from pigs fed the PC or NC diets and diets supplemented with AvMn (dietary treatment × display time, P = 0.04). Results of this study indicate that feeding an additional 350 ppm of Mn from MnSO^sub 4^ above the maintenance requirements of growing-finishing pigs does not beneficially affect live pig performance but may improve pork color and delay discoloration of pork during retail display. [PUBLICATION ABSTRACT]