title: Germ cell transplantation in felids: a potential approach to preserving endangered species.
abstract: With the exception of the domestic cat, all members of the family Felidae  are considered either endangered or threatened. Although not yet used for this  purpose, spermatogonial stem cell (SSC) transplantation has a high potential  to preserve the genetic stock of endangered species. However, this technique  has not previously been established in felids. Therefore, we developed the  necessary procedures to perform syngeneic and xenogeneic SSC transplants (eg,  germ cell [GC] depletion in the recipient domestic cats, enrichment and  labeling of donor cell suspension, and the transplantation method) in order to  investigate the feasibility of the domestic cat as a recipient for the  preservation and propagation of male germ plasm from wild felids. In  comparison with busulfan treatment, local x-ray fractionated radiation was a  more effective approach to depleting endogenous spermatogenesis. The results  of both syngeneic and xenogeneic transplants revealed that SSCs were able to  successfully colonize and differentiate in the recipient testis, generating  elongated spermatids several weeks posttransplantation. Specifically, ocelot  spermatozoa were observed in the cat epididymis 13 weeks following  transplantation. As donor GCs from domestic cats and ocelots were able to  develop and form mature GCs in the recipient environment seminiferous tubules,  these findings indicate that the domestic cat is a suitable recipient for SSC  transplantation. Moreover, as modern cats descended from a medium-size cat  that existed approximately 10 to 11 million years ago, these results strongly  suggest that the domestic cat could be potentially used as a recipient for  generating and propagating the genome of wild felids.
authors: Laboratory of Cellular Biology, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil 31270-901.
authors: Robson C
authors: RC
authors: Silva
authors: Guilherme M J
authors: GM
authors: Costa
authors: Samyra M S N
authors: SM
authors: Lacerda
authors: Sérgio R
authors: SR
authors: Batlouni
authors: Jaqueline M
authors: JM
authors: Soares
authors: Gleide F
authors: GF
authors: Avelar
authors: Karin B
authors: KB
authors: Böttger
authors: Silvério F
authors: SF
authors: Silva
authors: Maria S
authors: MS
authors: Nogueira
authors: Leonardo M
authors: LM
authors: Andrade
authors: Luiz R
authors: LR
authors: França