It has been claimed that outdoor-reared suckling piglets do not need iron supplementation. According to practical experience, outdoor-reared and non-iron-supplemented piglets show a lower performance in comparison with their iron-supplemented counterparts. The purpose of the present study was to determine the effect of iron supplementation on outdoor reared suckling piglets. In a large Hungarian outdoor pig production unit, 4691 piglets were assigned to one of two treatment groups. Piglets in group 1 (n ¼ 2344): received no iron supplementation, whereas piglets in group 2 (n ¼ 2347)
were intramuscularly injected in the neck on day 3 postpartum with 1.5 ml of Ferriphor
10% solution (TAD Pharmaceutical GmbH, Bremerhaven, Germany). Animal weights, morbidity, haemoglobin concentration and mortality were recorded and analysed. At weaning the iron-injected piglets were significantly (P<0.05) heavier. The iron-supplemented piglets also revealed significantly (P<0.01) less preweaning morbidity and mortality and higher (P<0.01) blood haemoglobin concentration compared with the non-injected ones. This study suggests that in order to prevent pre-weaning losses and support piglet health and weight performance, iron supplementation should be administered to piglets in outdoor pig production units.