Lactoferrin was crude extracted by salt-out and organic reagent precipitation from bovine colostrums, and the optimal isolating conditions were obtained through the single factor and orthogonal experiments. The result showed that salt-out at pH 8.5 with 80 % (NH4)2SO4, precipitation with 60 % ethanol. The result from SDS-PAGE showed that the purity of the lactoferrin was 48 ...