Colostrum is a great source of IgA antibodies that have been known to help support and build up a healthy immune system. Supplied to all first born mammals, colostrum comes from mother’s first milk and helps nourish a newborn. Four Leaf Rover Colostrum is from bovine and is dense in proline-rich-polypeptide (PRP), which has been researched to help relieve allergy symptoms and autoimmune disease.