Fatal acute babesiosis in captive grey wolves (Canis lupus) due to Babesia canis.

Two adult male Eurasian grey wolves belonging to a group of 12 animals, kept in an open air 15,000-m(2) enclosure at the Bear Farm facility near Veresegyháza, Hungary, were found dead in September 2002. Another 2 wolves died during the same period, but laboratory examination of their carcasses was not possible. During necropsy both animals were found to be in a good body condition. Oral mucosa, conjunctiva, sclera, and subcutaneous tissues revealed severe jaundice. The liver, gall bladder, and spleen were enlarged. The kidneys were paler than normal, and petechial haemorrhages were also seen under their fascia. Small, round Babesia-like organisms, 1.5-2 μm in diameter, were demonstrated in large numbers in stained impression smears made from the spleens of both animals. PCR amplification and sequencing identified Babesia canis. There are very few reports on babesiosis in the grey wolf, and our findings draw attention to the potential threat posed by B. canis that will probably have to be taken into account in future ex situ and in situ wolf conservation efforts.