The invention provides application of
ferritin in a
feed additive, and belongs to the technical field of feed preparation. The
feed additive is prepared by constructing recombinant
bacillus subtilis for expressing deacetylated nereis
ferritin, expressing the deacetylated nereis
ferritin, carrying out ultrasonic splitting on thalli and carrying out
spray drying on a splitting solution. Compared with unmutated nereis ferritin, the amount of
binding iron of the deacetylated nereis ferritin is increased by 44.62%. The serum
iron content of piglets fed with the deacetylated nereis ferritin
feed additive is 2.51 mu g / mL, the health rate is 98%, the serum
iron content and the health rate are both higher than those of a
glycine iron and non-mutated nereis ferritin feed additive group, the
feed conversion ratio is 1.70: 1, and the serum
iron content and the health rate are lower than those of the
glycine iron and the non-mutated nereis ferritin feed additive group. The deacetylated nereis ferritin feed additive has a good iron supplementing effect on piglets, and can improve the
health condition of the piglets, promote the growth of the piglets and effectively increase the breeding benefits.