**Acknowledgements**

VML and APS wish to thank CAPES (Brasília, Brazil) and FAPERGS (Porto Alegre, Brazil) for the financial support. Also, TGS and APS are grateful to CNPq (Brasília, Brazil) for the research fellowship and financial support (proc. 307352/2013-7 and proc. 441407/2014-5, respectively). We are also thankful to the local people from Derrubadas municipality (RS, Brazil). This work was performed by following the licenses provided by the Secretaria Estadual do Meio Ambiente, RS, Brazil (SEMA, #144/2013), ICMBIO/MMA (#39772-1), and the Ethics Committee on Animal Use of the Federal University of Santa Maria (#060/2013).
