This is the first successful report on producing the endangered domestic fowl, Kureko Dori (KD), which is a Kumamoto prefectural natural treasure, using germline chimeras transplanted from primordial germ cells (PGCs) in practice. The attempt was made to produce germline chimeras between KD fowl, as a model of rare and/or endangered poultry, and common White Leghorn (WL) for the proliferation of KD individuals. The PGCs of KD were collected from embryonic blood at stages +to +0 (H & H) and preserved in liquid nitrogen until injection. A certain number of frozen-thawed PGCs were picked up under a phase contrast microscope, and injected into the peripheral vein of WL embryos (common poultry) at stages +, to +.. We obtained one male and 0 females as the putative germline chimera, they were raised until sexual maturity, and the progeny test was performed by mating them with KD of the opposite sex to analyze the e$ciency of germline chimera. The average rate of o#spring originating from transplanted PGCs of KD was only +..ῌ, and the maximum was /.-ῌ from all /11. These KD o#spring derived from the KD-WL germline chimeras also achieved fertility as normal. These results show that rare and/or endangered birds can proliferate through producing germline chimeras between the same species of bird.