Abstract
Zygotes, ookinetes, oocysts and sporozoites of L. caulleryi were found in the Culicoides arakawae, parasitized on the infected chickens. Thirteen chickens were infected by the injection of a suspension of Culicoides arakawae within 2-7 days after the feeding on the infected chickens. The time from the injection of the suspention of the sporozoites to the appearance of the parasites in the stage of gametogony, was about 14 days. Gametogony was found in the peripheral blood for at least 10 days. These facts show that the Culicoides arakawae transmits L. caulleryi of the chicken, in Japan. It is thought that these findings may be the first reported on the intermediate host of the Leucocytozoon of the chicken, up to this time.
