1. Reproductive Sciences Program (N.D, K.M.B, H.J.B, M.B., E.A.Y., F.J.K.), University of Michigan, Ann Arbor, Michigan 48109-0404
2. Departments of Physiology (K.M.B., F.J.K.), University of Michigan, Ann Arbor, Michigan 48109-0404
3. Animal and Food Sciences Division (G.K.B.), Lincoln University, Canterbury 8150, New Zealand
4. Mental Health Research Institute (E.A.Y.), University of Michigan, Ann Arbor, Michigan 48109-0404