Thu, Aug 05, 2021:On Demand
Background/Question/Methods
Most organisms are infected with multiple parasites at the same time and how they are able to withstand these pressures could affect their fitness. Energetic resources of individuals may be utilized to fight off (i.e. resist) infections, withstand (i.e. tolerate) infections, or be stolen by parasites. The relationships between energetic resources and investment in reproduction are similarly complex; individuals in better condition may be able to invest more in reproduction, yet reproduction may come with energetic costs. To start to untangle and better understand these complex, likely-bidirectional interactions, we conducted a 3-year mark-recapture deworming experiment in wild populations of Peromyscus sp. mice.
Results/Conclusions We examined the relationships among single and co-infections and host condition, reproduction and survival. Additionally, we utilized the experimental parasite removal to quantify how these fitness-related host traits are affected by the presence of parasitic nematodes. While nematodes affected host condition and co-occurring infections, we found little evidence that they affected the net reproduction of female hosts, though effects on males were more pronounced. We also detected evidence of interactions between nematodes and microparasites, and of multiplicative fitness costs of co-infection. By examining the interactions between co-infection, condition, reproduction, and survival, we can better understand the challenges and trade-offs organisms face in a world full of parasites.
Results/Conclusions We examined the relationships among single and co-infections and host condition, reproduction and survival. Additionally, we utilized the experimental parasite removal to quantify how these fitness-related host traits are affected by the presence of parasitic nematodes. While nematodes affected host condition and co-occurring infections, we found little evidence that they affected the net reproduction of female hosts, though effects on males were more pronounced. We also detected evidence of interactions between nematodes and microparasites, and of multiplicative fitness costs of co-infection. By examining the interactions between co-infection, condition, reproduction, and survival, we can better understand the challenges and trade-offs organisms face in a world full of parasites.