Abstract

Background:
Captive jaguars (Panthera onca) may be exposed to infectious agents through animal-derived feed, contact with domestic or synanthropic animals, and contaminated environments.

Aim:
This study evaluated the serological evidence of exposure to Toxoplasma gondii, Neospora caninum, smooth Brucella species, and Leptospira spp. in jaguars housed at ten zoological institutions in five states of central and southwestern Mexico.

Methods:
Between May and June 2023, serum samples were collected from 40 captive jaguars in the states of Mexico, Michoacán, Puebla, Tlaxcala, and Oaxaca. Anti-T. gondii IgG antibodies were detected using an indirect ELISA based on recombinant SAG1 and GRA7 antigens. Antibodies against N. caninum were assessed using a commercial competitive ELISA, whereas seroreactivity to smooth Brucella species was evaluated using a multispecies indirect ELISA and the Rose Bengal test. Antibodies against a panel of Leptospira serovars were examined using the microscopic agglutination test. Exact 95% confidence intervals were calculated using the Clopper-Pearson method, and associations with geographic regions were assessed using Fisher's exact test.

Results:
The overall apparent seroprevalence was 87.5% (35/40) for T. gondii and 70.0% (28/40) for N. caninum. Antibodies against smooth Brucella species were detected in 10.0% (4/40) of the jaguars, with seroreactive animals identified in Michoacán, Puebla, and Oaxaca. Seroreactivity to Leptospira was uncommon: Canicola and Icterohaemorrhagiae were each detected in 5.0% (2/40) of the animals, and Pyrogenes were detected in 2.5% (1/40). Reactive animals were found in Puebla and Oaxaca. No statistically significant association was detected between the geographic region and serological status of any of the investigated agents.

Conclusion:
Captive jaguars at the participating institutions showed frequent serological evidence of previous exposure to T. gondii and N. caninum, whereas seroreactivity to smooth Brucella species and Leptospira serovars was less common. These findings provide baseline evidence of previous pathogen exposure and support longitudinal surveillance with molecular confirmation and more complete individual and management records.

Key words: Brucella species; Leptospira spp.; Neospora caninum; Panthera onca; Toxoplasma gondii.