Porcing reproductive and respiratory syndrome oral vaccine production in plants

A method for preparing a porcine reproductive and respiratory syndrome virus protein is disclosed. This method involves obtaining a gene encoding the desired protein, then inserting the gene within a vector suitable for transforming a plant and transforming a plant with the vector. Following growth of the transformed plant, the desired tissues may be harvested and the protein is extracted from the harvested tissue. This invention is also directed at a method of immunizing pigs against porcine reproductive respiratory syndrome comprising harvesting the transformed plant to obtain harvested tissue and feeding the harvested tissue to pigs, or extracting the protein from the harvested tissue and administering the protein to the pig as a food supplement, or as an injection. However, direct grazing of the plant tissue prior to harvested may also be employed as desired.