Semen and sperm cell processing and preservation systems, and methods of producing a mammal and methods of producing mammalian embryos are disclosed. The present invention is directed to sperm cell preservation, fertilization, and insemination, maintaining or enhancing sperm quality and addressing one or more sperm cell characteristics, such as viability, motility, functionality, fertilization rates, and pregnancy rates. Further, sperm cell characteristics may be addressed within the context of various collection, handling, separation, storage, transportation, usage, fertilization, or insemination techniques.

Semen and sperm cell processing and preservation systems, and methods of producing a mammal and methods of producing mammalian embryos are disclosed. The present invention is directed to sperm cell preservation, fertilization, and insemination, maintaining or enhancing sperm quality and addressing one or more sperm cell characteristics, such as viability, motility, functionality, fertilization rates, and pregnancy rates. Further, sperm cell characteristics may be addressed within the context of various collection, handling, separation, storage, transportation, usage, fertilization, or insemination techniques.

The present invention refers to a method for reconstructing a non-human animal embryo, to a method for generating a nonhuman animal and to a non-human animal or non-human animal reconstructed embryo obtainable by the methods according to the invention. The method of somatic cell nuclear transfer (SCNT) has a step of transiently expressing or inducing the uptake of a protein involved in male sperm maturation, such as protamine or transition protein, in the somatic donor cell before nuclear transfer.