The present invention provides certain donor animals, tissues and cells that are particularly useful for xenotransplantation therapies. In particular, the invention includes porcine animals, as well as tissue and cells derived from these, which lack any expression of functional alpha 1,3 galactosyltransferase (aGT) and express one or more additional transgenes which make these animals suitable donors for xenotransplantation of vascularized xenografts and derivatives thereof. Methods of treatment and using organs, tissues and cells derived from such animals are also provided.
