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Abstract For energetically limited organisms, life‐history theory predicts trade‐offs between reproductive effort and somatic maintenance. This is especially true of female mammals, for whom reproduction presents multifarious energetic and physiological demands.Here, we examine longitudinal changes in the gut virome (viral community) with respect to reproductive status in wild mature female chimpanzeesPan troglodytes schweinfurthiifrom two communities, Kanyawara and Ngogo, in Kibale National Park, Uganda.We used metagenomic methods to characterize viromes of individual chimpanzees while they were cycling, pregnant and lactating.Females from Kanyawara, whose territory abuts the park's boundary, had higher viral richness and loads (relative quantity of viral sequences) than females from Ngogo, whose territory is more energetically rich and located farther from large human settlements. Viral richness (total number of distinct viruses per sample) was higher when females were lactating than when cycling or pregnant. In pregnant females, viral richness increased with estimated day of gestation. Richness did not vary with age, in contrast to prior research showing increased viral abundance in older males from these same communities.Our results provide evidence of short‐term physiological trade‐offs between reproduction and infection, which are often hypothesized to constrain health in long‐lived species.
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Methodological Considerations for Assessing Immune Defense in Reproductive Females
Synopsis One of the key foci of ecoimmunology is understanding the physiological interactions between reproduction and immune defense. To assess an immune challenge, investigators typically measure an immune response at a predetermined time point that was selected to represent a peak response. These time points often are based on the immunological responses of nonreproductive males. Problematically, these peaks have been applied to studies quantifying immune responses of females during reproduction, despite the fact that nonreproductive males and reproductive females display fundamentally different patterns of energy expenditure. Previous work within pharmacological research has reported that the response to the commonly-used antigen keyhole limpet hemocyanin (KLH) varies among individuals and between females and males. In this heuristic analysis, we characterize antibody responses to KLH in females with varying reproductive demands (nonreproductive, lactating, concurrently lactating, and pregnant). Serum was taken from one animal per day per group and assessed for general and specific Immunoglobulins (Igs) G and M. We then used regression analysis to characterize the antibody response curves across groups. Our results demonstrate that the antibody response curve is asynchronous among females with varying maternal demands and temporally differs from the anticipated peak responses reflected in standardized protocols. These findings highlight the importance of multiple sampling points across treatment groups for a more integrative assessment of how reproductive demand alters antibody responses in females beyond a single measurement.
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- PAR ID:
- 10251152
- Date Published:
- Journal Name:
- Integrative and Comparative Biology
- Volume:
- 60
- Issue:
- 3
- ISSN:
- 1540-7063
- Page Range / eLocation ID:
- 732 to 741
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/icb/icaa098
