[1] Kansas State Univ, Coll Vet Med, Vet Med Teaching Hosp, Manhattan, KS 66506 USA
[2] Kansas State Univ, Coll Vet Med, Dept Pathobiol, Manhattan, KS 66506 USA
[3] NW Zoo Path, Monroe, WA 98272 USA
[4] Univ Georgia, Coll Vet Med, Dept Pathol, Athens, GA 30602 USA