Relationships between ELISA values and RBT titers. A total of 179 serum samples from 17 different species of odontocetes were tested by iELISA, gELISA, cELISA, and RBT. (A) Relationship between RBT titers and iELISA. (B) Relationship between RBT titers and gELISA. (C) Relationship between RBT titers and cELISA. White circles correspond to RBT titles, dotted lines indicate cutoff values, and the stars correspond to serum samples from culture-positive dolphins.