Effects of a simulated infection on feeding and locomotor behavior of anurans

Author(s)

Thaysa Gomes de Oliveira

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2022-11-29

Examining board members

Carlos Arturo Navas Iannini; Carlos Guilherme Becker; Carla Bonetti Madelaire; Gisele Akemi Oda

• Advisor: Carlos Arturo Navas Iannini

Abstract

The central theme of this research is the effect of immune system activation on anuran behavior. We emphasize that immune responses, food and locomotion demand metabolic and energy resources, and usually occur in parallel, which can generate a trade-off. In addition, when an animal is sick, the immune responses can lead to behavioral depression, which may be associated with the economy of these resources. In amphibians, it has been observed that a simulated infection can induce behavioral depression, with reduced feeding and locomotion. However, studies with invasive species have shown that these animals maintain their ability to disperse (locomotor behavior) even when they are sick. Thus, this dissertation is composed of five parts. The general introduction presents the interface between the feeding and locomotor behavior of amphibians, the immune responses, the mechanisms linked to simulated infections by LPS, and the costs associated with both behaviors and the activation of the immune system. In chapter 1, we studied the feeding and locomotor behavior of anurans of the species Aquarana catesbeiana after simulated infection by LPS injections. The treatment with LPS reduced the feeding and locomotion of the individuals, evidencing the behavioral depression in this species. In chapter 2, we investigated the impact of simulated infection by LPS injections on the locomotor behavior of male and female anurans of the species Xenopus laevis. Treatment with LPS reduced the locomotor performance of the animals, but had no effect on voluntary movements and did not show to be different between the sexes, in most of the variables observed. In chapter 3, we investigated the impact of simulated infection by LPS injections on the locomotor behavior of anurans of the species Xenopus laevis (invasive species) and anurans of the species Xenopus allofraseri (non-invasive species). The simulated infection reduced locomotor performance in both species, however the invasive species was less affected. Finally, the general discussion explains the integration of research carried out in the three chapters and how they contribute to the discussion of each point covered in the general introduction, showing a dialogue between amphibian physiology and ecology in the context of diseases. (AU)

• FAPESP's process: 19/18250-0 - Termorregulatory, food and locomotor response of individuals of anurus Lithobates catesbeianus species injected with lipopolysaccharides (LPS) as a pro-inflammatory stimulus
• Grantee: Thaysa Gomes de Oliveira
• Support Opportunities: Scholarships in Brazil - Master