PS3-18. The Inclusion of Ferrous Sulphate as an Iron Source in the Diet Can Increase Post-Weaning Diarrhea in Weaned Pigs

Weaner diets are commonly formulated with ferrous sulphate as a source of iron to improve hemoglobin (Hb) concentrations after weaning. Inorganic iron forms such as Ferrous sulphate have a lower oral bioavailability and can also fuel bacterial proliferation (Abbas et al., 2022) The advantage of Ferrous sulfate is that it is cost-effective and has a long shelf life (Lee et al., 2008). Organic iron derived from animal sources such as bloodmeal, spray-dried plasma or iron chelates is an alternative to inorganic sources as it is more bioavailable, but comes at an additional cost (Abbas et al., 2022). It was hypothesized that ferrous sulphate would significantly increase diarrhea compared with organic iron sources. Pigs were scored individually daily for the occurrence of post-weaningdiarrhea. The diarrhea index scored diarrhea daily on a scale of 0-2, with 0 being no diarrhea, 1 mild diarrhea and 2 as severe diarrhea. After data collection, the index was weighted with a score of 1 representing 0.5 and a score of 2 given a weight of 1. Scores were then entered into the following equation: Equation 1: Diarrhea index equation Results showed that Ferrous sulphate significantly increased post-weaning diarrhea relative to the control diet (1.55 vs 0.24 p < 0.05), as measured by a diarrhea index, but ferrous sulphate diarrhea occurrence was not different from other iron sources. In conclusion, ferrous sulphate did increase post-weaning diarrhea compared to a diet with no iron source but not compared to any other dietary treatments. Therefore, it can be concluded that the source of dietary iron does little to affect the occurrence of post-weaning diarrhea in weaner pigs for seven days after weaning. References: Abbas, M., Hayirli, Z., Drakesmith, H., Andrews, S. C., & Lewis, M. C. (2022). Effects of iron deficiency and iron supplementation at the host-microbiota interface: Could a piglet model unravel complexities of the underlying mechanisms? Front Nutr, 9, 927754. https://doi.org/10.3389/fnut.2022.927754 Lee, S. H., Shinde, P., Choi, J., Park, M., Ohh, S., Kwon, I. K., Pak, S. I., & Chae, B. J. (2008). Effects of Dietary Iron Levels on Growth Performance, Hematological Status, Liver Mineral Concentration, Fecal Microflora, and Diarrhea Incidence in Weanling Pigs. Biological Trace Element Research, 126(1), 57-68. https://doi.org/10.1007/s12011-008-8209-5