Patent ID: 7476776

Claim:
A method of improving the ability to prepare germline chimeric chickens, which comprises the steps of: (a) isolating primordial germ cells (PGCs) from a chicken embryonic gonad; (b) culturing said PGCs in vitro for at least 10 days on a gonadal stroma feeder cell layer such that PGCs that are positive for stage specific embryonic antigen-1 (SSEA-1) are obtained; (c) injecting the PGCs that are positive for SSEA-1 into the dorsal aorta of a recipient chicken embryo without prior treatment of said cultured PGCs with Ficoll; and (d) incubating and hatching an egg containing the recipient chicken embryo such that a germline chimeric chicken is obtained, wherein the efficiency of germline transmission of the PGCs injected is between 44.7% and 49.7%.