Project Number: 1245-31000-105-00
Project Type: Appropriated

Start Date: Dec 03, 2012
End Date: Dec 02, 2017

Objective:
Objective 1: Identify the physiological impacts of hypothermic storage on the carbohydrate, lipid, protein, calcium homeostasis and residual mRNA components of poultry, swine and striped bass sperm. Objective 2: Elucidate the cellular and molecular mechanisms controlling sperm selection and storage in the female reproductive tract of poultry. Objective 3: Determine the genetic component of post-thaw sperm survivability by identifying genetic markers and residual mRNA profiles associated with poultry and swine lines demonstrating superior and inferior sperm cryosurvival. Objective 4: Elucidate the cellular and molecular mechanisms impacted by cold storage in the fertile egg blastoderm in poultry.

Approach:
In the food animal industries, generating offspring that possess economically important traits is most effectively accomplished by artificial insemination (AI) in poultry and swine or in vitro fertilization (IVF) in striped bass. The efficiency of AI and IVF for swine, poultry and striped bass is limited by the inability to store male gametes at refrigerated or frozen temperatures without a significant loss in sperm function. Improving hypothermic semen storage methods for these species is dependent upon a fundamental understanding of the cellular and molecular biology of the sperm cell and how prolonged exposure to hypothermic storage impacts sperm physiology. Previously, we identified physiological components of sperm cells that are negatively impacted by hypothermic storage, and also have demonstrated the impact of genetics on sperm cryosurvival. The current plan will expand on this knowledge by investigating methods to prevent sperm membrane alterations and maintain calcium homeostasis during hypothermic storage, and exploring the feasibility of using genetic markers to predict sperm cryosurvival. We will use transciptome analysis to study the physiological phenomenon of prolonged semen storage in the hen’s oviduct. We also will test the possibility that residual mRNA in sperm can serve as a predictor of sperm cryosurvival and fertility. A new objective important for the poultry industry is evaluating the impact of storing eggs at cool temperatures for long time periods on embryonic development. This comprehensive research approach will permit development of more efficient methods of preserving poultry, swine, and fish semen, and increase hatchability following egg storage under hypothermic conditions.