PSIV-9 A Multistate Evaluation of an Additional Iron Injection Administered to Piglets Before Weaning

A cooperative study utilizing 514 weanling pigs from 7 experiment stations was conducted to determine the effects of an additional iron injection administered to piglets before weaning on growth performance and hematological measures. All pigs received an initial iron injection at the time of processing postfarrowing. At each station, pigs were assigned to either the control or an added-injection treatment by pairing two same-sex pigs with a BW difference ≤ 0.453 kg within a litter. One pig within each pair received the additional iron injection (same dose received at processing) 3 to 5 days preweaning. Once weaned, both the control and added-injection group received common station-specific nursery diets. Body weight was recorded weekly by all stations. Blood samples were also collected at second injection, weaning, 14 and 28 days postweaning by 3 of the 7 stations. All data were subjected to ANOVA with the model containing the terms treatment, station, and treatment by station interaction. Average daily gain (Table 1) was greater for the added-injection group during d 0 to 14 (212.5 vs. 202.6 g, P = 0.03) which resulted in an increase in d 14 BW (P = 0.05). Although there was no treatment effect for overall ADG (d -4 to d 28), the tendency for a treatment by station interaction (P = 0.09) illustrated both responsive and nonresponsive stations, indicating that iron status was not the most limiting factor for growth at all stations. Hemoglobin concentration was greater (P < 0.0001) for the added-injection group at weaning and d 14 postweaning. In conclusion, an additional iron injection administered before weaning may lead to early success in the nursery resulting in a heavier BW in subsequent periods; however, the beneficial effects of an additional iron injection are likely dependent on herd status and characteristics.