Date of Award
2-9-2023
Document Type
Thesis
Degree Name
Biology, MS
First Advisor
Lorin Neuman-Lee
Committee Members
Brook Fluker; Travis Marsico
Call Number
LD 251 .A566t 2022 F54
Abstract
Ecoimmunology examines the relationship between the physiology of an organism, its immune responses, and the external environment. As such, this field is critical to answering important questions in ecology, physiology, and evolution, and it can be vital in making policy and conservation decisions. As the only ectothermic amniotes, class Reptilia represents a group of unique study organisms. However, in comparison to other vertebrate taxa, this group has remained relatively understudied in the field of ecoimmunology. Though reptilian immunology has gained some attention in the last decade, we still lack data assessing immunity across the four orders of class Reptilia. Immune function is a highly energetically costly process, though vital to the survival of an organism. Reproduction, while also critical to the fitness of an organism, is also very energetically expensive. During the reproductive season, energy allocation is expected to prioritize reproductive activities such as mating, offspring development, and oviposition or birth. However, when encountering a stressor, the balance between reproductive and maintenance processes may be disrupted to fuel the stress response, a process crucial to immediate survival. To address the knowledge gaps in reptilian immunity across all four orders of class Reptilia, I first conducted a thorough literature search and analyzed the literature to understand common immunological techniques used, patterns of research within and between orders, and identified gaps in our current knowledge. To begin to address the gaps that I found, I experimentally assessed energetic tradeoffs among immunity, stress, and reproduction for three watersnake species throughout Northeast Arkansas in May 2020 and from April–October 2021. I subjected animals to an acute stressor by restraint. I collected blood samples prior to the stressor and then at 30, 60, and 120 minutes post initial handling. I performed bacterial killing assays to assess functional innate immunity. I measured estradiol, progesterone, testosterone, and corticosterone concentrations using radioimmunoassays to evaluate reproductive investment and stress-responsiveness. By building a comprehensive framework of overall reptilian innate immunity, we can make better informed decisions on what work remains to be done in the field of reptilian immunology and ecoimmunology. Energetic tradeoffs between the immune system, reproductive system, and the stress response are complex. This study adds to the growing body of literature allowing us to understand the energetic shifts in wild organisms and how they prioritize immunity throughout critical life history events.
Rights Management
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Field, Emily Katherine, "Investigating the reptilian innate immune system: A review and examination of the relationship between immunity, stress, and reproduction" (2023). Student Theses and Dissertations. 207.
https://arch.astate.edu/all-etd/207
