Energy expenditure and body temperature variations in llamas living in the High Andes of Peru

Alexander Riek,Rodolfo Marquina Bernedo,Catherine Hambly,Walter Arnold,Thomas Ruf,Martina Gerken,Anna Stölzl,John R Speakman

doi:10.1038/s41598-019-40576-9

Abstract

Some large herbivores exhibit seasonal adjustments in their energy metabolism. Therefore, our aim was to determine if the llama (one of the most extensively kept livestock breeds) exhibits seasonal adjustment of their energy expenditure, body temperature and locomotion, under its natural high altitude Andean habitat. For this purpose, energy expenditure, body temperature and locomotion were measured in seven non-pregnant llama dams for ten months on the Andean High Plateau (4400 m above sea level). Daily energy expenditure was measured as field metabolic rate using the doubly labelled water method at four different measurement times. Additionally, a telemetry system was used to continuously record activity, body temperature (3 min intervals) as well as the position (hourly) of each animal. The results show that llamas adjusted their body temperature and daily energy expenditure according to environmental conditions. Furthermore, llamas under high altitude Andean climatic conditions exhibited a pronounced daily rhythm in body temperature and activity, with low values at sunrise and increasing values towards sunset. Llamas also had remarkably low energy expenditure compared to other herbivores. Thus, despite the domestication process, llamas have not lost the ability to adjust their body temperature and daily energy expenditure under adverse environmental conditions, similar to some wild herbivores.

Highlights

Endothermic mammals have to invest a substantial amount of energy to keep their species specific body temperature (Tb) within a narrow limit of 37–39 °C especially with changing environmental conditions[1]
Llamas and alpacas have been reported to live in lowlands in pre-Columbian times[15], they are typically concentrated in the high Andean regions
It is noteworthy that South American camelids have been shown to possess an extraordinary high blood oxygen affinity[18]

Summary

Introduction

Endothermic mammals have to invest a substantial amount of energy to keep their species specific body temperature (Tb) within a narrow limit of 37–39 °C especially with changing environmental conditions[1]. With the exception of bears and badgers, were thought not to use such metabolic mechanisms to save energy until some studies on cervid species[6] and other larger ruminants[7,8] indicated that they exhibit some form of seasonal adjustment in their metabolism. Apart from climatic challenges and feed shortages, llamas and alpacas are confronted with the impact of high altitude, i.e. reduced atmospheric pressure Under these conditions, energy efficiency is a prerequisite for survival. The aim of our long-term study was to determine if the llama, exhibits seasonal and/or daily adjustment mechanisms with regard to energy expenditure and Tb in its natural habitat of the high Andes in South America

Objectives

Results

Conclusion