PSV-12 - Evaluation of Iron Source and Level on Nursery Pig Performance and Blood Hemoglobin Concentrations

Abstract: The objective of this study was to evaluate effects of dietary iron (Fe) source and concentration on nursery pig performance and blood hemoglobin concentrations. A total of 960 newly weaned, mixed sex pigs (5.7 ± 0.40 kg BW) were allotted to four dietary treatments using a complete randomized design (24 pens/treatment, 10 pigs/pen). All pigs were fed a three-phase corn-soybean meal-based diet . The four diets were: 1) 100 ppm Fe from iron sulfate; 2) 100 ppm Fe from an iron-amino acid complex (Fe-AA; ProPath^® Fe 150), 3) 50 ppm Fe from Fe-AA and 4) 25 ppm Fe from Fe-AA. Pigs were weighed on day 0, 7, 21 and 42, and feed disappearance measured to calculate ADG, ADFI and G:F within phase and overall. Blood hemoglobin was assessed on day 0, 21 and 35. Pen was considered the experimental unit and all data were analyzed using the mixed procedure of SAS with treatment as a fixed effect. Iron treatment did not alter pig performance (ADG, ADFI and G:F) in phase 1, 2 or 3 (P > 0.05). Overall, ADG was similar between treatments (0.46, 0.45, 0.45 and 0.44 kg/d, respectively, P > 0.05). Similarly, overall ADFI was similar between treatments (0.61, 0.60, 0.58 and 0.62 kg/d, respectively, P = 0.31). Overall 42-day G:F did not differ between treatments (P > 0.05). Blood hemoglobin concentrations (g/dL) showed a quadratic response over day post-weaning (P < 0.001); however, no treatment or treatment by day interaction were reported (P > 0.05). Altogether, these data demonstrate that feeding 25-100 ppm of Fe-AA provided similar performance to 100 ppm Fe from an inorganic source. Additionally, pigs did not have altered hemoglobin levels or become Fe deficient when diets were supplemented with Fe-AA at levels below NRC requirement.