Cardiorespiratory responses to temperature changes during the larval stage of a native amphibian specie of the Cerrado, Boana lundii (Anura, Hylidae)

Abstract

Nowadays, we are living in a scenery of climate change that is expected to increase the average temperature of the planet, with the occurrence of extreme temperature peaks. It is known that amphibians correspond to an important part of Brazilian biodiversity and that their physiological, ecological and life history characteristics make them quite susceptible to changes in the environment. Therefore, it is essential to identify the most vulnerable species to global warming. Thus, the present study aims to determine the tolerance and thermal sensitivity of a native species of anuran, Boana lundii, during larval stage. To this end, two groups of tadpoles will be acclimatized at different temperatures (15 and 25°C) and cardiorespiratory responses, such as heart rate (fH) and frequency of buccal movements (fB), as well as the metabolic rate will be evaluated under resting conditions and after autonomic blockade, using a non-invasive methodology. Furthermore, mitochondrial respiration of the heart will be determined at both acclimation temperatures. In addition, in order to verify the Maximum Critical Temperature another group of tadpoles will be exposed to gradual increases in temperature (2 °C.h-1) and their cardiorespiratory parameters and mitochondrial respiration will be evaluated. (AU)