2006 Annual Report 4d.Progress report. This report serves to document research conducted under a non-funded cooperative agreement between ARS and West Virginia State University. Additional details of research can be found in the report for the parent project #5364-31000-007-00D, Integrated Systems for Increasing Production Efficiency of Sheep. An experiment was conducted with sheep to determine whether ablation of large ovarian follicles late in the estrous cycle, and thus stimulating the recruitment of a new cohort of follicles and ovulation of developmentally younger follicles, would improve embryonal and fetal survival. All data have been collected and are currently being analyzed to determine whether the ablation treatment altered embryonal and fetal survival.