This invention provides compositions and methods for treating and vaccinating and inducing an immune response against a Her2/neu antigen expressing tumor in a non human animal. An exemplary method of treating a Her 2/neu expressing tumor growth or cancer in a non human animal the method comprising the step of administering a recombinant Listeria comprising nucleic acid molecule encoding a fusion polypeptide wherein said fusion polypeptide comprises a Her2/neu chimeric antigen fused to an additional adjuvant polypeptide is provided.