Effects of different parenteral iron treatment regimens on hematology characteristics, serum concentrations of hepcidin, and growth performance in pigs fed nursery diets supplemented with copper

Objective: To determine the effects of iron treatments on hematology, hepcidin, and growth in weaned pigs fed copper-supplemented diets. Materials and methods: Pigs were allocated to a 3 x 2 factorial arrangement of treatments (4 pens/treatment combination, 3 pigs/pen) with factors being intramuscular iron (200 mg at birth; 100 mg at birth and weaning [22.4 days of age]; or 100 mg at birth and 14 days of age) and dietary copper (14 [control] or 250 ppm [supplemented]). Blood was sampled at days 0, 7, and 49 post weaning. Results: Pigs receiving 100 mg iron at birth and weaning, but not pigs in the other groups, had hemoglobin concentrations consistent with iron deficiency at day 0 (iron treatment x day, P <.001). For pigs receiving 100 mg iron at birth and 14 days of age, hepcidin concentrations were greater in control pigs than copper-supplemented pigs (iron treatment x diet, P =.06). A diet x day interaction (P =.07) existed for hepcidin, with concentrations greater in control vs copper-supplemented pigs on day 49. Pigs receiving iron at day 14 of age had the greatest (P =.01) weaning weights. Gain from day 0 to 7 was enhanced (P =.03) by 250 ppm copper but nursery performance (day 0-49) was unaffected by iron treatment. Implications: Pigs receiving 100 mg iron at birth were iron deficient at weaning. Treatment with iron at 14 days of age could improve weaning weights and prevent iron deficiency at weaning. Age -related increases in hepcidin were decreased by additional copper supplementation.