Author Affiliations +
ROBERT F. SILVA,1 ALY M. FADLY,1 SCOTT P. TAYLOR2
1U.S.D.A., Agricultural Research Service, Avian Disease and Oncology Laboratory, 3606 E. Mount Hope Rd., E. Lansing, Michigan 48823, USA
2USDA-APHIS, Center for Veterinary Biologics, 510 South 17 Street, Suite 104, Ames, Iowa 50010, USA