Chickens were immunized with two synthetic peptide / keyhole limpet hemocyanin (KLH) conjugates. These synthetic peptides corresponded to different and nonphosphorylated regions of the Tau gene product, but are shared between the human (NP_05819, NCBI) and mouse (P01637, NCBI) sequences. After repeated injections, immune eggs were collected, and the IgY fractions were purified from the yolks. These IgY fractions were then affinity-purified using a peptide column, and the concentrations of the eluates adjusted to 200 ug/ml. Finally, equal volumes of both of these affinity-purified anti-peptide antibodies were mixed, and the preparation was filter-sterilized.