Cardiac evaluation in free-ranging giant anteaters (Myrmecophaga tridactyla) in the Brazilian Cerrado

Abstract

The giant anteater (Myrmecophaga tridactyla) is classified as a Vulnerable species, but these animals are regularly brought into rescue centers and are also kept in zoos around the world. They occupy a highly specialized dietary niche with a feeding ecology that is difficult to replicate under human care. This can lead to numerous nutrition-related health problems, including frequent cardiomyopathies. Establishing reference parameters for free-ranging animals is an important tool to assess the health of animals under human care. For this reason, a cardiac assessment through plasma troponin I concentrations, vertebral heart score (VHS) based on thoracic radiographs, and echocardiographic parameters were established for 11 free-ranging giant anteaters in the Cerrado savanna of Mato Grosso do Sul, Brazil. The troponin I concentrations were all lower than 0.2 ng/ml, the cutoff limit for detection in the assay used. The mean VHS in the right lateral projections was 7.49, a value almost identical to cats (7.5) and lower than dogs (9.7). A complete echocardiographic assessment is provided and compared with previous case reports. This paper validates the diet-related origin hypothesis for common dilated cardiomyopathy in giant anteaters. This is the first published study with radiographic and echocardiographic parameters for free-ranging giant anteaters, providing important reference parameters for future giant anteater in situ and ex situ conservation initiatives. This work highlights the benefits of veterinary research comparing health parameters for animals living under and outside of human care.