Avian Piroplasm Babesia sp. Isolated from Crested Serpent Eagles (Spilornis cheela) in Yaeyama Archipelago

Babesia sp. was found in the erythrocytic cytoplasm of 6 crested serpent eagles (Spilornis cheela) in Yaeyama Archipelago, Okinawa, Japan. The examined birds showed 0.1±0.09% (Avg±SE) parasitemia. Considering the morphologic characteristics and morphometrics of haemosporidian parasite, we assumed that they were closely related to B. moshkovskii found in the birds of the family Accipitridae. However, some morphometric differences were observed between the Babesia sp. isolated from the crested serpent eagles and haemosporidian parasite from other host species mentioned previously; thus, further inspection using molecular analysis is required for accurate identification. No haemosporidian parasite-induced pathognomonic clinical signs were observed. This is the first report on Babesia infection in Japanese wild birds and a new host record for an avian piroplasm parasitising crested serpent eagles.