Investigations on seasonal differences in the energy allocation of free ranging llamas (Lama glama) under Central European and high altitude Andean conditions

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Endothermic animals have to keep their body temperature within a narrow limit with changing environmental conditions. However, this comes at a high energetic cost. Nevertheless, there are indications that some ungulates can exhibit some form of an energy saving mechanism when ambient temperatures are low and/or food availability is scarce. This phenomenon has been shown for large ungulates such as roe deer, red deer and for the wild ancestor of the horse, the Przewalski horse. There are speculations that livestock species lost the ability to reduce their energy expenditure under food shortages and/or adverse environmental conditions, since they were housed and selected under constant nutrient supply without selection pressure for maintaining a seasonal, cyclic adaptation. However, empirical confirmation of a supposedly lower adaptability of livestock species compared to their wild counterparts is still missing. Furthermore, it is still unknown to what extend such seasonal adjustments with regard to energy allocation are present in extensively kept livestock species. In that regard the llama is particularly well suited as a model animal since it represents one of the most robust domestic animal breeds which, after the domestication model, can be referred to as a primary population. Therefore, the aim of the study is to determine if the llama, one of the most extensively kept livestock breeds, exhibits seasonal adjustment mechanisms in terms of energy expenditure and locomotion under Central European and high altitude Andean climatic conditions. The proposed study would be the first in a mammal that combines the doubly labelled water method for measuring energy expenditure with a telemetry system measuring locomotion, body temperature and heart rate, as well as determining the distances covered by a GPS. In combination these data will give a very detailed picture about the interaction between energy expenditure and energy savings in an animal.