[Determination of clotting factor VIII activity in mammals using the one-stage clotting and the chromogenic methods].

: Two different laboratory assays exist for the determination of clotting factor VIII activities in human plasma. One method is based on the one-stage clotting principle, the other one on the chromogenic principle. To evaluate the suitability for veterinary medicine human plasma and plasma of ten mammalian species (pig, cattle, dog, cat, zebra, llama, snow leopard, greater kudu, horse-like antelope, mink) were examined with each method. Factor VIII activities in human plasma determined using both assays were in a good agreement. Results of factor VIII activities in plasma of mammals obtained with both methods were similar, if a species-specific reference plasma was used. The practicability of the chromogenic method was reduced. However, the factor VIII activities differed nonsystematically up to 500% between both methods, if a human plasma was used as a reference plasma. Determination of factor VIII activities in plasma of mammals using the chromogenic assay cannot be recommended.