A differential diagnostic criterion for Babesia major and Babesia bigemina vermicules from tick haemolymph.

Babesia major mature and immature vermicules in the haemolymph of Haemaphysalis punctata were measured and found to be significantly larger than vermicules of Babesia bigemina. Mature B. major vermicules had a mean length of 15.53 micrometer and mature B. bigemina vermicules had a mean length of 11.79 micrometer. This difference provides a new criterion for the differentiation of the two species.