Resistance to coinfection among feline viral leukemia, feline panleukopenia, anaplasmosis, and cytauxzoonosis in a free-living jaguar (Panthera onca) in southern Brazil

The transmission of infectious diseases between domestic and wild carnivores has raised growing concerns for the conservation of species, such as jaguars (Panthera onca). Wild and domestic animals sharing the same or adjacent environments can exchange various pathogens harmful to both. This study describes the clinical and biological monitoring of an 11-month-old jaguar diagnosed with feline leukemia virus, feline panleukopenia, and cytauxzoonosis in Iguaçu National Park, the largest remaining of Inner Atlantic Forest in Brazil. Despite the presence of these pathogens, detected via PCR, the animal showed no clinical signs of disease during 12 months of camera trap monitoring, exhibiting normal physical and behavioral development. The results suggest differences in the immune response of wild jaguars compared to domestic or captive felids, where these pathogens typically cause severe and often fatal diseases. The study highlights the need for further research into the dynamics of these infections in wild felids and underscores the importance of continuous monitoring for species conservation.