1. Liggins Institute and National Research Centre for Growth and Development (N.M.T., A.M.N., M.H.V., J.L.M., B.H.B.), The University of Auckland, Private Bag 92019, Auckland, New Zealand
2. Department of Animal Sciences (S.S.D.), Purdue University, West Lafayette, Indiana 47907
3. Department of Pediatrics (R.R.S.), Indiana University School of Medicine, Indianapolis, Indiana 46202