This experiment was conducted to evaluate the effects of organic iron complex on sow reproductive performance and iron status of nursing pigs. At day 84 of gestation, a total of 58 sows at five-parity were randomly assigned to two groups receiving diets containing organic iron complex (n=33) and ferrous sulfate (n=25). According to a 2×2 factorial design of treatments, nursing pigs (2.09±0.34 kg) within a given litter were divided into two groups and given either an injection with or without iron (0 vs. 200 mg/pig) on day three of lactation. The feeding trial lasted for 51 days, including 30 days of gestation and 21 days of lactation.
The results showed that organic iron complex did not improve the reproductive performance of sows or the growth performance of piglets. In particular, nursing pigs injected with iron had greater individual body weight at day 21 of lactation compared to pigs that were not treated with iron (P<0.05). Compared with ferrous sulfate, organic iron complex significantly increased the Cu content in mature milk (P<0.01), and the serum iron concentration at day one of lactation (P<0.05), as well as ceruloplasmin activity at day 21 of lactation (P<0.01). Piglets from sows fed organic iron complex tended to have a greater total iron binding capacity (P=0.08) and ceruloplasmin activity (P=0.05) at day 10 of lactation, and tended to have a higher concentration of hemoglobin (P=0.08), total iron binding capacity (P<0.01) and serum iron (P<0.01) at day 21 of lactation compared with piglets from sows fed ferrous sulfate. Piglets injected with iron had a greater red blood cell count (P<0.01), hemoglobin (P<0.01), serum iron (P<0.01) and total iron binding capacity (P<0.05) at day 10 and 21 of lactation compared to piglets that were not treated with iron.
In conclusion, organic iron complex had minor positive effects on the iron status of sows and nursing pigs, but did not significantly improve the performance of sows and their offspring. Therefore, attempts to replace the commonly used Fe injection with a maternal organic iron complex dietary supplement failed to prevent iron-deficiency anemia of nursing pigs.
Jun Wang, Desheng Li, Lianqiang Che, Yan Lin, Zhengfeng Fang, Shengyu Xu, De Wu. Influence of organic iron complex on sow reproductive performance and iron status of nursing pigs. Livestock Science. Volume 160, February 2014, Pages 89–96. doi:10.1016/j.livsci.2013.11.024