The recovery and cryopreservation of epididymal sperm are essential tools to preserve genetic stocks of valuable domestic or wild animals under adverse conditions and also as an alternative source of gametes in cases of human infertility. This technique is recommended after death or when it is not possible to recover semen by usual methods. Sperm from the epididymis has been studied by many authors in different species. Cryopreservation is the most effective method for long-term preservation of genetic material from valuable breeding individuals. The protocols and diluents used for cryopreservation of conventional semen are well established, but many challenges remain working with sperm extracted directly from the epididymis. The spermatozoa retrieved from the cauda epididymis have special features, such as the absence of seminal plasma and large numbers of distal cytoplasmic droplets, which necessitate special handling, both for cryopreservation and for fertilization. For these reasons, it is important to describe in detail the features needed to cryopreserve sperm from the epididymis.
Part of the book: Cryopreservation in Eukaryotes