The present invention generally relates to methods of eliciting an immune response in an aquatic species subject. In particular, an immunomodulator composition is used to induce an immune response to enhance the subject’s ability to fight pathogens.本發明大體上是有關在水生物種個體中誘發免疫反應的方法。特別地,使用免疫調節劑組合物來引起免疫反應,以增強個體對抗病原的能力。