1. Cincinnati Children's Center for Breastfeeding Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
2. Center for Biobehavioral Health, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio.
3. Department of Animal Sciences, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus, Ohio.
4. Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio.
5. Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio.
6. Department of Microbiology, College of Arts and Sciences, The Ohio State University, Columbus, Ohio.
7. Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio.
8. Division of Epidemiology, College of Public Health, The Ohio State University, Columbus, Ohio.