tissue from neonatal donors into immunodeficient mice.
Although so far limited to rabbits [2] and pigs [3], using
sperm obtained from testicular grafts grown in host mice,
intracytoplasmic sperm injection (ICSI) has been used
successfully to produce live offspring with normal reproductive
potential [4]. Thus, xenografting of fresh testicular
tissue combined with ICSI makes it possible to obtain a new
generation from young donors that have not yet reached
sexual maturation and cannot be used for reproduction.
However, when applying these techniques for conservation
of genetically valuable animals such as rare breeds, endangered
species, or those with genetic modifications that
result in neonatal lethality, testicular tissues will often need
to be stored until offspring production becomes necessary.
Therefore, effective preservation of donor testis has been
indispensable for practical application.