Experimental procedures regarding the generation of chicken embryonic stem cell-like cells. EGK stage X blastoderm-derived singularized cells were seeded on mitomycin C-treated MEFs. After 7 days of culture in chicken ES medium, chicken embryonic stem cell-like cells began to emerge as colonies and continuously proliferated. The white dotted circle indicates chicken embryonic stem cell-like cells. Scale bar: 100 μm.