Concentrations of cortisol and testosterone related to relationships between members of a bachelor group of red deer stags

Bruno Esattore, M.Sc.

Doctoral thesis

Abstract:

The main aims of this project were to verify the existence of different typologies of inter-individual relationships within the bachelor group of red deer (Cervus elaphus), to test their consistency in time and across different social contexts and to investigate their effects on the concentrations of testosterone and cortisol. The results presented in this dissertation not only show that there are different and well-separated strategies of associations [i.e., "Associates", "Indifferent", "Non-Associates"], with animals more interaction-prone ("Fighters") and animals less interaction-prone ("Non-Fighters"), but highlight that the recorded differences are consistent across modifications of the social environment and have interesting repercussions on the concentrations of cortisol, rather than on the testosterone. Our findings led us to a preliminary investigation of the personality of our target species and of its link with the dominance hierarchy. Out of the 15 behavioural items composing the questionnaire, five showed acceptable agreement between raters and four of these loaded on the component "Confidence/Aggressiveness”, which could describe variation in agonistic behaviour. Even if our latest results represent a step forward in the understanding of the personality of the red deer, we recommend further investigations.

Keywords

Red deer, Testosterone, Cortisol, Personality

Language used: English

Date on which the thesis was submitted / produced: 27. 1. 2021

Thesis defence

• Supervisor: prof. Ing. Luděk Bartoš, DrSc.

Czech University of Life Sciences Prague

Faculty of Agrobiology, Food and Natural Resources

Doctoral programme / field:
Animal Science / General Animal Science