PS9-24. Effects of Early-gestational Parenteral Iron Administration on Maternal Iron Biomarkers in Prolific Sows Under Commercial Conditions.

Abstract Previous research has reported high sow anemia prevalence (>50%) in U.S commercial herds and has linked anemia to negative reproductive outcomes and increased sow removal risk. The objective of this study was to evaluate the effects of early-gestation parenteral iron dextran administration on sow iron status under commercial conditions. A total of 235 TN70 sows (parities 1 to 9, average parity 4.2) were enrolled in early gestation (30 ± 2 d of gestation) and followed through weaning (19 ± 2 d of lactation). Sows were allotted by parity, initial blood hemoglobin (Hb), and prior reproductive performance to one of three parenteral iron dextran treatments initiated at enrollment: 0 mg (CONFe; n = 77), 2,500 mg (MODFe; n = 79), or 5,000 mg (HIGHFe; n = 79). Injections were administered intramuscularly into the trapezius muscle. CONFe sows did not receive an injection, MODFe sows received one 12.5-mL injection (2,500 mg), and HIGHFe sows received two 12.5-mL injections (2,500 mg per site). Injections were administered slowly to minimize product loss and ensure proper intramuscular deposition. Blood Hb was measured on days 30 and 112 of gestation and day 19 of lactation using a HemoCue Hb 201+ system via ear-vein sampling. A subset of sows (N = 75; 25 per treatment) had jugular blood samples collected for serum iron, ferritin, total iron-binding capacity (TIBC), and plasma C-reactive protein. Data were analyzed using PROC MIXED of SAS with sow as the experimental unit. On day 112 of gestation, HIGHFe sows had greater blood Hb than CONFe sows (10.5 vs. 10.0 g/dL), with MODFe sows being intermediate (10.2 g/dL; P = 0.049). Serum TIBC tended to be greater in CONFe sows on day 112 of gestation than HIGHFe sows (482.7 vs. 454.4 µg/dL), with MODFe sows being intermediate (460.6 µg/dL; P = 0.094). Serum ferritin was greater in both HIGHFe (24.0 ng/mL) and MODFe (22.8 ng/mL) groups on day 19 of lactation than CONFe (17.2 ng/mL) (P = 0.005). Total born and liveborn were not affected by treatment; however, HIGHFe sows tended to have a lower stillborn rate than CONFe sows (5.2% vs. 7.8%), with MODFe sows intermediate (6.1%; P = 0.066). In conclusion, administration of 5,000 mg iron dextran in early gestation improved indicators of sow iron status and tended to reduce stillborn rate, suggesting that higher parenteral iron support during gestation may help address the high prevalence of anemia in modern sow populations.