Background: Reprogramming pig somatic cells into induced pluripotent stem cells (iPSCs) have promising applications in basic biology, disease model development and xenotransplantation. In the mouse, embryonic stem cell (ESC) technology has revolutionized the field enabling gene targeting, complex screening strategies and the creation of animals that show unique characteristics of interest. Recent breakthroughs utilizing induced pluripotent stem cell technology in the pig have made it possible to produce pig pluripotent stem cells that resemble germline chimeric competent mouse ESCs. However, an optimal culture system for piPSC expansion has yet to be developed. Most reports have maintained piPSCs in undefined systems that use xenoproducts and feeder layers, which are potential sources of contamination.