Abstract
The social behavior mechanisms have not been thoroughly reported in the solitary female striped dwarf hamster (Cricetulus barabensis). In this study, the handling bag test and neutral arena measurements were used to detect the changes of aggression in the face of rivals of different genders of wild striped dwarf hamsters. We found that female hamsters had the highest aggressive performance in proestrus, followed by estrus, and the lowest in metestrus and the dioestrus, and the increased aggression during the proestrus or estrus period was low-intensity aggression such as intimidation, shock, boxing and counterattack, or even ritualized non-harmful behaviors to drive away opponents. When confronted with male individuals, aggression in females decreased significantly during estrus. The concentration of plasma estradiol was the highest in estrus and the lowest in metestrus and dioestrus. In contrast, estrogen receptor 2 relative expression in the hypothalamus is the lowest in proestrus and highest in metestrus and dioestrus. Besides, both estradiol levels in plasma and estrogen receptor 2 mRNA in the hypothalamus were associated with aggression. These results will broaden our understanding of the molecular mechanism of how breeding phenotype is an essential driver in changing the social behavior of female Cricetulus barabensis.
Highlights
Aggressive behavior is an evolutionarily conserved, heritable trait essential for survival and fitness [1]
4.1 Aggressive behaviors and Resting metabolic rate (RMR) changed with the estrous cycle
We used female hamsters as the animal model to investigate the mechanism of aggression
Summary
Aggressive behavior is an evolutionarily conserved, heritable trait essential for survival and fitness [1]. One possible factor determining the fitness of these different strategies is population density. A study on the natural population of Microtus pennsylvanicus found that female aggression levels increased significantly at relatively low densities [2]. Social pressures may limit subordinate age and sex groups’ access to concentrated food sites [3]. Aggression is an essential social behavior that promotes survival and reproductive fitness across animal systems [5]. Individuals with intense aggression can occupy a higher social class and increase the individual’s fitness. While research on the neuroendocrine mechanisms underlying this complex behavior has traditionally focused on the classic neuroendocrine model, circulating gonadal steroids are transported to the brain and act on neural circuits closely related to aggression [5]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
