A comparation between different iron sources on growth performance, iron utilization, antioxidant capacity and non-specific immunity in Eriocheir sinensis

This study was to determine the effects of different iron sources on the growth performance, iron utilization, antioxidant capacity and non-specific immunity in Eriocheir sinensis. Juvenile crabs (3.29 ± 0.06 g) were fed with six basic diets supplemented with 100 mg/kg iron in the form of ferrous sulfate (S-100), ferrous fumarate (F-100), ferrous glycine (G-100), ferrous sulfate + ferrous fumarate (S-50 + F-50), ferrous sulfate + ferrous glycine (S-50 + G-50) and ferrous fumarate + ferrous glycine (F-50 + G-50) for 10 weeks. The crab in the G-100 group and the S-50 + G-50 group had higher weight gain, specific growth rate and lower whole-body total lipid than those in the S-100 group. The expression levels of divalent metal ion transporter 1 and ferroportin in the intestine and hepatopancreas were significantly enhanced in the G-100 group and the S-50 + G-50 group compared with the S-100 group. Crabs fed the G-100 diet possessed higher hemolymph iron, transferrin concentration and iron contents in the whole body, hepatopancreas and muscle than in other treatments. In addition, the total antioxidant capacity in the G-100 group and the activities of acid phosphatase and phenoloxidase in the G-100 group and the S-50 + G-50 group significantly improved compared to the S-100 group. This study demonstrates that ferrous glycine might be the proper iron source for improving growth performance, iron utilization, antioxidant capacity and non-specific immunity of E. sinensis, and can be a source of effective iron supplementation in aquafeed.