Obtaining farm animal embryos in vitro

This paper reviews the basic knowledge about obtaining farm animal embryos in vitro with special focus on differences among species and application of this procedure in the future. In vitro production of farm animal embryos consists of in vitro maturation (IVM) of oocytes, in vitro fertilization (IVF) of matured oocytes, and in vitro culture (IVC) of embryos. Oocytes can be collected from live animals (by laparotomy, laparoscopy, Ovum Pick Up) or from slaughtered ones (by puncture, sectioning). Usually immature oocytes are isolated, and during IVM they reach maturity. Matured oocytes are cultured with sperm (IVF), leading to the formation of zygotes. In the case of fertilization problems (horse, pig), intracytoplasmic sperm injection is used. The zygotes are usually cultured (IVC) to the morula and blastocyst stages. These embryos can be transferred to recipients or frozen/vitrified. Offspring have been obtained after transfer of cattle, sheep, goat, pig and horse embryos. This procedure can be used in animal breeding, biotechnology, medicine, and basic research.