Abstract
In order to elucidate the factors in extension of blood coagulation time in cetaceans, a screening test of blood coagulation time was performed for four species of delphinids in the Cetacea and one species of pinniped in the Carnivora, and blood coagulation factors were examined in three species of cetaceans and one species of pinniped. Extension of active partial thromboplastin time (APPT) and an obviously lower level of XII factor (Hageman factor) activity were clearly observed in the cetaceans. These factors seemed to involve the extension of blood coagulation time in the cetaceans. On the other hand, we obtained different values in the pinniped, which did not show any extension of blood coagulation time.
