Patent ID: 6960462

Claim:
An animal feed additive comprising (a) at least one purified acid-stable subtilisin and (b) one or more fat soluble vitamins and/or water soluble vitamins, and (c) one or more trace minerals, wherein the acid stability of the subtilisin means that the activity of the pure subtilisin, in a dilution corresponding to A 280 =1.0, is at least 40% of the reference activity of the subtilisin, wherein the activity of the subtilisin is measured after two hours incubation at a temperature of 37° C. in a buffer of 100 mM succinic acid, 100 mM HEPES, 100 mM CHES, 100 mM CABS, 1 mM CaCl 2 , 150 M KCl, and 0.01% Triton X-100 (pH 3.5); and wherein the reference activity is measured after two hours incubation at a temperature of 5° C. in the same buffer but adjusted to pH 9.0, wherein the activity and reference activity are measured after these incubations, at 25° C. in Suc-AAPF-pNA (pH 9.0).