Abstract

The little spotted cat (Leopardus tigrinus) is the smallest neotropical Brazilian species of felid, similar to the domestic cat in size and body structure. This species is listed in CITES Appendix I and it is considered insufficiently known by IUCN. Information about occurrence of diseases and infections in such a species are sparse. Dirofilariasis has been reported worldwide, mainly in domestic dogs, but also in other carnivores. Among felids, occurrences have been reported in tiger (Panthera tigris), lion (Panthera leo), leopard (Panthera pardus), clouded leopard (Neofelis nebulosa) and snow leopard (Uncia uncia). The etiologic agent, the nematode Dirofilaria immitis, when adult, usually lives inside the heart and pulmonary artery of the host. Though domestic cats can lodge adult Dirofilaria without signs of disease, severe complications and sudden death are frequent. Hematophagous mosquitoes are intermediate hosts. A wild adult female little spotted cat was found recumbent, with hemoptysis and anisocoria in a veterinary clinic in the southeastern coastal town of Ubatuba, São Paulo, Brazil, where there are protected areas of Atlantic Rainforest. Although receiving medical care, the animal died and necropsy was performed at LAPCOM, FMVZ-USP. Macroscopic examination revealed that the animal had an excellent body condition, was lactating, and had no sign of trauma, which was confirmed by postmortem radiography. Small and large intestines were heavily infested with worms; some were found in the heart as well. The right ventricle was enlarged, with eccentric hypertrophy at the histopathologic examination, pulmonary lesions suggested secondary hypertension due to parasitism, including endoarteritis and the presence of four intravascular microfilaria in small arteries. The cardiac nematodes were identified by morphologic methods as Dirofilaria immitis. Two males and one female were found at the right ventricle and a female at the left ventricle. Because of the uncommon localization at left ventricle, we suggest the occurrence of sudden death by cardiac parasitism. From our knowledge, this is the first reported case of Dirofilaria immitis infection in a neotropical felid. It is not possible to determine if the little spotted cat is a natural host or if the agent was introduced in the region by domestic carnivores, considering that there are many confirmed cases of domestic canine dirofilariasis in Ubatuba. We suggest adoption of control measures for domestic dog populations that can act as reservoirs of several infectious agents for wild animals.

Acknowledgments

Aquário de Ubatuba, CENAP-IBAMA; Financial support: CAPES.