Start Date: Jul 24, 2007
End Date: Jul 23, 2012
In the food animal industries, production of offspring that possess economically important traits is most effectively accomplished by artificial insemination (AI) or in vitro fertilization (IVF), where semen from a few males is distributed among a large number of females. The poultry and swine industries use AI in their breeding programs to accelerate genetic advancement, while the striped bass industry relies on IVF. Because of gaps in our fundamental knowledge of sperm biology, the fate of sperm in the oviduct and impact of freezing on sperm function, there has been limited success in the long-term preservation of poultry, swine and bass germplasm, and existing methodologies are not adequate for the needs of these industries. Development of effective semen storage methodology necessitates a scientific foundation addressing the cellular and molecular biology of both the sperm cell and the female cells that interact with sperm after insemination. Experiments in this project will address these fundamental questions by focusing on (1) sperm membrane composition and energetics before and after hypothermic storage, (2) impact of sperm on oviductal epithelial cell gene expression and secretory activity, and (3) potential genetic basis of sperm cryosurvival. Included in this project are several alternative strategies for germplasm preservation: introduction of cryoprotectants intracellularly; dietary modification of sperm cell membranes; and use of cryopreserved testicular cells as an alternative means of male germplasm cryopreservation. This systematic approach will address the gaps in our knowledge and permit development of novel and/or more efficient methods of preserving poultry, swine and fish semen.