Livestock Semen Biotechnology and Management

Modern livestock breeding is basically dependent on the proper use of semen for artificial insemination of females and of other reproductive biotechnologies such as the production of embryos in vitro for embryo transfer. Both these techniques have made possible not only the wide dissemination of genetic material onto breeding populations but also enhanced the selection of best sires, owing to the development of better diagnostic techniques for sperm function and of preservation of seminal material over time. Although use of liquid semen cooled to room temperature, to intermediate temperatures (+16-20°C) or chilled (+5°C) dominates in some livestock species (swine respectively small ruminants), cryopreservation is rule in bovine and it is advancing in other species by the design of new containers, freezing methods and the use of better insemination strategies. Reliable semen diagnostics is absolutely essential to disclose which semen is to be processed/cryopreserved but also to aim determination of a potential fertilizing capacity in the laboratory, thus saving costs prior to artificial insemination. However, there is a yet no single laboratory method that accurately prognoses fertility in livestock, requiring use of a battery of diagnostic methods. Novel techniques for optimal use of ejaculates (low-dose) and intrauterine deposition of semen throughout species are those management techniques that shall increase our capabilities for better diagnostics/selection of semen/male potential fertility, of cryopreservation techniques and a more rational dissemination of genetics.