Seronegativity of Iberian ibex (Capra pyrenaica) against Toxoplasma gondii and Neospora caninum is consistent with eco-epidemiological and environmental features in Mediterranean mountainous areas

Abstract

Knowledge of pathogen epidemiological dynamics and habitat ecological features is essential for wildlife population and health monitoring and management. Toxoplasma gondii and Neospora caninum are two broadly distributed multi-host parasites that affect both wild and domestic animals and, in the case of T. gondii, cause zoonosis. This study reports the seroprevalence of both parasites in Iberian ibex (Capra pyrenaica), a mountain wild ruminant native to the Iberian Peninsula, from the Natural Space of Sierra Nevada (NSSN) in southeastern Spain. Serum from 146 Iberian ibexes were analysed using two in-house ELISA techniques. The positive and doubtful sera were further checked by Western Blot (WB). Seventeen ibexes (11.6 %; 95 % confidence interval 6.4-16.7) were positive for T. gondii and seven (4.8 %; 95 % confidence interval 1.3-8.2) for N. caninum. However, no sera were positive to T. gondii nor to N. caninum by WB. Using at least two different serological techniques is recommended when they are not validated for the target host species. The NSSN is a hypoendemic area for T. gondii and N. caninum, probably determined by the reduced abundance and restricted distribution of their definitive hosts. This would explain the hypoendemic situation in the NSSN and the lack of specific antibodies against these two parasites in the Iberian ibex population. This eco-epidemiological scenario can be challenged by climate and anthropogenic changes, recommending long-term monitoring Iberian ibex population and health, both as a conservation measure for the species and as an indicator of the potential impact of global change on high mountain ecosystems.

This study was performed within the context of the Educational Collaboration Agreement signed by the University of Murcia and the Consejería de Medio Ambiente y Ordenación del Territorio of the Junta de Andalucía. The authors are grateful by the support received by the research group RNM-118 from the Plan Andaluz de Investigación. The study benefitted from funding of the Spanish Ministerio de Economía y Competitividad through the grants CGL2012-40043-C02-01, CGL2012- 40043-C02-02, and CGL2016-80543-P. Ana Huertas-López was supported by a postdoctoral contract Margarita Salas (University of Murcia) from the Program of Requalification of the Spanish University System (Spanish Ministry of Universities) financed by the European Union — NextGenerationEU [grant number R-1593/2022]. Special thanks are also due to the park rangers and fieldworkers of the NSSN and, particularly, to José López Pérez, Isidro Puga González, Elías Martínez Ortiz, Apolo Sánchez Lao and Antonio Rodríguez Dueñas for their professional and personal involvement in the study.