(1) The two TGEV epitopes were immunogenic when injected intraperitoneally (IP) into mice as hybrid CIpG subunits, chimeric CS31A polymers, or recombinant bacteria; (2) the chimeric CS31A fibrillae elicited TGEV antibodies in the serum of mice reactive with TGEV peptides and native TGEV; and (3) mice inoculated orally with the recombinant bacteria produced IgA intestinal antibodies reactive against the CS31A fibrillae and TGEV S c peptide.