Impact of Iron Supplementation on Growth Performance, Iron Homeostasis and Redox Balance of Suckling Piglets

Abstract

This study evaluates the effects of intramuscular injection or oral supplementation of iron on the growth performance, iron homeostasis, and redox status of suckling piglets. A total of 94 newborn piglets, selected from 8 healthy sows, were randomly allocated into 4 treatment groups during the lactation period, receiving injections of normal saline without iron (CON, n = 23), intramuscular dextran injection of bound iron at 2 mL (200 mg Fe) on postnatal day 3 (PND 3) (FeDex, n = 24), oral supplementation from PND 2 to 13 with 10 g of FerkoFer^® containing 2.2 g Fe per day (FeOra, n = 23), or both FeDex and FeOra (FeDPO, n = 24). Piglets were weighed individually at birth and PND 21. Blood samples were collected on PNDs 1, 7, 14, and 21. Piglets in the CON group had lower body weight on PND 21 compared with piglets in the FeDex, FeOra, and FeDPO groups (0.46-1.05 kg decrease, p < 0.05), while piglets in the FeDPO group had the highest weaning weight across all groups (p < 0.05). The levels of hemoglobin (HGB) and serum iron (SI) in FeDPO piglets were significantly higher than in all other groups on PNDs 14 and 21 (p < 0.05). Moreover, the red blood cell (RBC) levels in the FeDPO and FeOra piglets were significantly higher than that in FeDex piglets on PND 21 (p < 0.05). In addition, serum superoxide dismutase (SOD) and catalase (CAT) activities in both FeOra and FeDPO piglets were significantly higher than those of piglets in CON and FeDex piglets on PND 21 (p < 0.05), whereas malondialdehyde (MDA) content in FeDex piglets was higher than that in CON piglets (p < 0.05). Collectively, the current results indicate that the combination of intramuscular injection and oral supplementation is a more effective strategy to improve the growth performance of suckling piglets, associated with higher hemoglobin and serum iron levels, as well as the optimal redox status.

Keywords: blood parameters; growth performance; iron supplementation; suckling piglets.

Figure 1

Effects of iron supplementation strategies on hemoglobin and serum iron levels of piglets at different ages. (A) Hemoglobin (HGB) (B) Serum iron (SI). Values are means and standard errors represented by vertical bars, n = 10 per treatment. ^a–d Different letters mean significantly different for different groups at p < 0.05. Control treatment (CON); Intramuscular injection of dextran iron treatment (FeDex); Oral iron treatment (FeOra); both FeDex and FeOra iron supplementation treatment (FeDPO).

Figure 2

Effect of iron supplementation strategies on redox index of piglets at different ages. (A) Total glutathione peroxidase (GSH-Px), (B) Total superoxide dismutase (SOD), (C) Malondialdehyde (MDA) and (D) Catalase (CAT). Values are means and standard errors represented by vertical bars, n = 10 per treatment. ^a–c Different letters mean significantly different for different groups at p < 0.05. Control treatment (CON); Intramuscular injection of dextran iron treatment (FeDex); Oral iron treatment (FeOra); both FeDex and FeOra iron supplementation treatment (FeDPO).