[Frontiers in Bioscience E4, 1111-1126, January 1, 2012]

[Frontiers in Bioscience E4, 1111-1126, January 1, 2012]

Endocrine relationships between rank - related behavior and antler growth in deer

Ludek Bartos¹, George A. Bubenik², Erika Kuzmova^{1, 3}

1Department of Ethology, Institute of Animal Science, Praha 10 - Uhrineves, 104 01, Czech Republic, ²Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada, ³Department of Ecology, Charles University, Praha, Czech Republic

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Antler development: 3.1. Antler growth and testosterone; 3.2. Antler growth and IGF-1.; 3.3. Antler development and castration; 3.4. Antler development and IGF-1 in different deer species
4. In vitro cultivation of antler tissues in relation to IGF-1 and testosterone
5. Antler development, IGF-1, testosterone and "double castration"
6. Discussion
7. Perspective
8. Acknowledgement
9. References

1. ABSTRACT

In this review, we analyze endocrine aspects of the relationships between antlerogenesis and rank-related behavior. The explanation of these relationships has been based on the presumption that the antler growth is regulated by hormones modulated by agonistic behavior. Originally, we assumed that these relationships are primarily testosterone dependent. In the eighties, it was reported that the insulin-like growth factor 1 (IGF-1) is the antler-stimulating hormone. This hypothesis was supposed to replace an earlier theory that the antler-stimulating hormones are either androgens or their derivatives. Here, we present historical and recent views on these issues. In particular, we analyze the arguments in favor and against the role of testosterone and IGF-1 in antler growth and present a comparison of the results obtained across some deer species. In this context, we review and discuss experiments with castration of various deer species and analyze data from papers dealing with in vivo studies. We conclude that testosterone and not IGF-1 is the main antler stimulating and regulating hormone, and that concentrations of testosterone may be modified by social behavior.