Biochemical and physiological parameters associated with Trypanosoma evansi prevalence in wild capybaras (Hydrochoerus hydrochaeris)

Abstract

Parasites can be detrimental to the health of wildlife populations and may negatively affect several aspects of the life history of their hosts. Investigating host health, therefore, is key to understanding important mechanisms of the host-parasite interaction at the individual and population levels. Recently, we reported a prevalence of 10% of Trypanosoma evansi in a population of capybaras (Hydrochoerus hydrochaeris) from Esteros del Iberá, Argentina; however, the impact of T. evansi infection in capybaras is unknown. The aim of this study was to explore associations between T. evansi infection and biochemical and physiological parameters in wild capybaras using blood samples (n=60) from a managed population of free-ranging capybaras from Esteros del Iberá. Infection by T. evansi was negatively associated with body condition, albumin, alpha-2 globulin concentrations, albumin:globulin ratio and eosinophil counts, and it was positively associated with spleen index and gamma-globulin concentrations. These results suggest that T. evansi infection may pose significant impact on the health of wild capybaras.