Energy metabolism and thermal physiology of toucan-toco(Ramphastos toco)

• Grant number: 13/12296-1
• Support Opportunities: Scholarships in Brazil - Master
• Start date: December 01, 2013
• End date: June 30, 2015
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Denis Otavio Vieira de Andrade
• Grantee: Jussara Nascimento Chaves
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated scholarship(s): 14/08919-6 - The effects of changes in day length on metabolism and mitochondrial enzyme activity of Catbirds (Dumetella carolinensis), BE.EP.MS

Abstract

Body temperature regulation, in face of environmental temperature fluctuations and/or changes in metabolic heat production, involves regulatory mechanisms associated to heat exchange. One of these mechanisms is the modulation of superficial temperature of specific areas of the body, by mean of vasomotor adjustments, that can either result in heat dissipation or heat conservation. Moreover, endotherms can also modulate heat exchange by altering the degree of exposition of given body parts to the environment or by a pilo (mammals) or ptilo (birds) autonomic response, or, finally by a seasonal change in pelage/plumage. These thermoregulatory adjustments allows for body temperature regulation, within a certain range of environmental temperatures, without any considerable increment in energetic cost. Such range or interval in which thermal homeostasis is attained without any appreciable increment in metabolic rate is referred to as Thermoneutral Zone (TNZ). Among endothermic vertebrates, TNZ is known to vary largely in its amplitude and lower and maximum limits. In temperatures below or above the lower (cold) or upper (hot) limits of the TNZ, respectively, animals incur in thermoregulatory responses that are energetically costly and, therefore, will cause metabolic rate to rise. The toco-toucan (Ramphastos toco) has a thermal window, the bill, recently described as highly efficient in the modulation of heat exchange. Accordingly, the present study aims to determine the potential contribution of the toco toucan extraordinary thermal window, i.e, the bill, in determining the amplitude and limits of this bird TNZ.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

CHAVES, Jussara Nascimento. Metabolismo energético e termorregulação do tucano-toco (Ramphastos toco). 2015. Master's Dissertation - Universidade Estadual Paulista (Unesp). Instituto de Biociências. Rio Claro Rio Claro.