Objective:
ARS and the Cooperator (University of Wyoming, Department of Animal Science, UW) desire to enter into this Cooperative Agreement for the purpose of determining the fertilizing capacity of ram semen frozen after a 24-hour holding period. Such an effort is consistent with the goals of the National Animal Germplasm Program (NAGP) and the UW. Making such an assessment is a critical step in determining how well ram semen that is collected at distant locations will hold while being shipped to the NAGP laboratory in Fort Collins.

Approach:
Semen will be collected from three UW rams and frozen at the time of collection (0 hour) and 24 hours after collection. Estrus will be synchronized on 140 western whiteface ewes. Upon synchronization of estrus the ewes will be artificially inseminated with freshly collected semen or semen frozen at the time of collection (0 hour or 24 hours after collection). Results will be derived from the number of pregnancies and live lambs born per ewe bred.