Effect of supplemental iron on finishing swine performance, carcass characteristics, and pork quality during retail display1

Abstract

Crossbred pigs (n = 185) were used to test the effects of dietary Fe supplementation on performance and carcass characteristics of growing-finishing swine. Pigs were blocked by BW, allotted to pens (5 to 6 pigs/pen), and pens (5 pens/block) were allotted randomly to either negative control (NC) corn-soybean meal grower and finisher diets devoid of Fe in the mineral premix, positive control (PC) corn-soybean meal grower and finisher diets with Fe included in the mineral premix, or the PC diets supplemented with 50, 100, or 150 ppm Fe from Availa-Fe (an Fe-AA complex). When the lightest block averaged 118.2 kg, the pigs were slaughtered, and bone-in pork loins were collected during fabrication for pork quality data. During the grower-I phase, there was a tendency for supplemental Fe to reduce ADG linearly (P = 0.10), whereas in the grower-II phase, supplemental Fe tended to increase ADG linearly (P = 0.10). Even though pigs fed NC had greater G:F during the finisher-I phase (P < 0.05) and across the entire trial (P = 0.07), live performance did not (P > or = 0.13) differ among dietary treatments. There were linear increases in 10th-rib fat depth (P = 0.08) and calculated fat-free lean yield (P = 0.06); otherwise, dietary Fe did not (P > 0.19) affect pork carcass muscling or fatness. Moreover, LM concentrations of total, heme, and nonheme Fe were similar (P > 0.23) among treatments. A randomly selected subset of loins from each treatment was further fabricated into 2.5-cm-thick LM chops, placed on styrofoam trays, overwrapped with polyvinyl chloride film, and placed in coffin-chest display cases (2.6 degrees C) under continuous fluorescent lighting (1,600 lx) for 7 d. During display, chops from NC-fed pigs and pigs fed the diets supplemented with 100 ppm Fe tended to have a more vivid (higher chroma value; P = 0.07), redder (higher a* value; P = 0.09) color than LM chops of pigs fed 50 ppm of supplemental Fe. Moreover, greater (P < 0.01) redness:yellowness ratios in chops from pigs supplemented with 100 ppm Fe indicated a more red color than chops from PC-fed pigs or pigs fed diets supplemented with 50 ppm Fe. In conclusion, however, increasing dietary Fe had no appreciable effects on performance, carcass, or LM characteristics, suggesting that current dietary Fe recommendations are sufficient for optimal growth performance, pork carcass composition, and pork quality.

Effects of L-carnitine and iron diet supplementations on growth performance, carcass characteristics and blood metabolites in fattening pigs

“…Saddoris et al (2003) observed that supplementing pig diets with 90 ppm Fe did not affect average backfat depth and longissimus muscle area, whereas Apple et al (2007) observed a linear increase in 10 th -rib fat depth as supplemental Fe from 50 to 150 ppm in diets. Our study showed a favourable effect of L-carnitine+Fe (as Fe-AA complex) supplement on the quality of pork carcasses.…”

“…Daily gains and feed conversion did not depend on 30 to 120 ppm Fe in the pig diet either (Yu et al 2000, Saddoris et al 2003. Apple et al (2007) found that 50 to 150 ppm Fe supplement in the grower and finisher diet increased the daily gains of growing pigs (55-68 kg BW), while not having any effect on growth performance in the finishing pigs. On the other hand, Liao et al (2005) found a rise of growth performance in 50 to 100 kg BW pigs obtaining the chelated Fe (1 g/kg diet).…”

“…In other studies, the positive effect of iron was observed on the daily gain in piglets (Rincker et al 2004) and fatteners (Liao et al 2005). Some studies also show that the supplementation of fatteners diet with Fe increases its content in meat and blood as well as positively affecting meat sensory quality (O'Sullivan et al 2003, Liao et al 2005, Apple et al 2007). …”

Lipid profile and quality of meat from finishing pig supplemented with minerals

“…On addition, the supplementation with Selenium can contribute for a better meat stability due to its protective action in the membranes, preserving it against the oxidizing agents (Calvo et al, 2016). The color of the pigment myoglobin is also dependent on the lipid oxidation degree in the meat (Apple et al, 2007).…”

Scientific opinion on the safety and efficacy of iron compounds (E1) as feed additives for all species: iron chelate of amino acids, hydrate, based on a dossier submitted by Zinpro Animal Nutrition Inc.

“…The applicant submitted four published papers (one in laying hens and three in pigs). The study in laying hens (Park et al, 2004) was not considered since product identity to that under application could not be established; the experiment with pigs for fattening (Apple et al, 2007) also could not be considered owing to weaknesses in design and reporting. The remaining two studies in piglets (Yu et al, 2000;Grela et al, 2005) support the general knowledge that iron from iron chelate of amino acids, hydrate, is a source of bioavailable dietary iron.…”