In the in vitro production of bovine embryos the conditions prevailing at the in vitro maturation (IVM) and in vitro fertilization (IVF) are important for the production of embryos. Both oocytes and spermatozoa should be properly selected. In order to get the best spermatozoa there should be a selection of semen donors as well as of motile spermatozoa. The latter can effectively performed when spermatozoa swim through a medium containing hyaluronic acid.