Despite the progress in freezing semen of domestic species, there is limited success with this technique in nondomestic species, in particular wild bird species. Thus, this study aims to exploit techniques relying on transplantation of of germ-line progenitor cells within or between species as an alternative tool to preserve germ plasm of endangered birds. According to the latest assessment by the World Conservation Union, about 12.4% of the total 9,856 extant bird species in the world are threatened with extinction. This uncertain future facing wild birds emphasizes the importance of captive breeding programs for the conservation of a number of avian species. Hence, in this study we investigated whether the transfer of purified testicular germ-line progenitor cells or a crude testicular cellular fraction from donor 6-week-old Japanese quails (as a model species for endangered birds) result in the recolonization of the gamma irradiated gonads of 32-week-old recipient domestic roosters. Since the morphology of mature sperm from quails and chicken differ considerably, we are able to easily distinguish them. Therefore, ejaculates from transplant’s recipients and non-sterilized controls are being collected twice a week starting 2 weeks before gamma-radiation (presently at 34 weeks), and subjected to standard semen analysis. Recipient chickens will be euthanized, and the testes will be histologically examined for evidence of spermatogenesis. Our results so far show that the chicken gonads are very susceptible to gamma-radiation, since spermatogenesis dropped from 4.52 ± 2.05 billion spermatozoa/mL to zero within one month. Although, we have not seen chicken producing quail sperm yet, it is interesting to note that the purified fraction of quail germ-line progenitor cells and not the crude testicular fraction seem to help in the re-establishment of chicken spermatogenesis. Since, only chickens receiving the purified fraction have reinitiated production of sperm. The experiments are still in progress and definitive answers will be available in a few months. If successful, we intend to conduct future studies using wild birds as donor species for transplantations in order to evaluate feasibility of rescueing genetic material from individuals that die prematurely or from endangered adult males with impaired spermatogenesis. In addition, we are also interested in investigating potential applications of this methodology in the preservation of genetic material from female wild birds, as well as in other species.