Immune mediated hookworm clearance and survival of a marine mammal decreases with warmer ocean temperatures
- University of Georgia, United States
- Pontificia Universidad Católica de Chile, Chile
- Universidad Andrés Bello, Chile
- Universidad Austral de Chile, Chile
- Universidad Santo Tomas, Chile
Abstract
Increases in ocean temperature are associated with changes in the distribution of fish stocks, and the foraging regimes and maternal attendance patterns of marine mammals. However, it is not well understood how these changes affect offspring health and survival. The maternal attendance patterns and immunity of South American fur seals were assessed in a rookery where hookworm disease is the main cause of pup mortality. Pups receiving higher levels of maternal attendance had a positive energy balance and a more reactive immune system. These pups were able to expel hookworms through a specific immune mediated mechanism and survived the infection. Maternal attendance was higher in years with low sea surface temperature, therefore, the mean hookworm burden and mortality increased with sea surface temperature over a 10-year period. We provide a mechanistic explanation regarding how changes in ocean temperature and maternal care affect infectious diseases dynamics in a marine mammal.
Data availability
All data generated or analysed during this study are included in the manuscript and/or uploaded as supplementary materials
Article and author information
Author details
Funding
Morris Animal Foundation (D16ZO-413)
- Mauricio Seguel
Society for Marine Mammalogy (Small grants in aid)
- Mauricio Seguel
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The experiments described in this manuscript were conducted with approval of the Chilean fisheries service and the University of Georgia animal use committee (IACUC #A2013 11-004-Y3-A0).
Copyright
© 2018, Seguel et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Immune mediated hookworm clearance and survival of a marine mammal decreases with warmer ocean temperatures
eLife 7:e38432.
https://doi.org/10.7554/eLife.38432
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