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Title: Timing and order of exposure to two echinostome species affect patterns of infection in larval amphibians
Abstract The study of priority effects with respect to coinfections is still in its infancy. Moreover, existing coinfection studies typically focus on infection outcomes associated with exposure to distinct sets of parasite species, despite that functionally and morphologically similar parasite species commonly coexist in nature. Therefore, it is important to understand how interactions between similar parasites influence infection outcomes. Surveys at seven ponds in northwest Pennsylvania found that multiple species of echinostomes commonly co-occur. Using a larval anuran host ( Rana pipiens ) and the two most commonly identified echinostome species from our field surveys ( Echinostoma trivolvis and Echinoparyphium lineage 3), we examined how species composition and timing of exposure affect patterns of infection. When tadpoles were exposed to both parasites simultaneously, infection loads were higher than when exposed to Echinoparyphium alone but similar to being exposed to Echinostoma alone. When tadpoles were sequentially exposed to the parasite species, tadpoles first exposed to Echinoparyphium had 23% lower infection loads than tadpoles first exposed to Echinostoma . These findings demonstrate that exposure timing and order, even with similar parasites, can influence coinfection outcomes, and emphasize the importance of using molecular methods to identify parasites for ecological studies.  more » « less
Award ID(s):
1655190 1655168 1655156
NSF-PAR ID:
10250181
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Parasitology
Volume:
147
Issue:
13
ISSN:
0031-1820
Page Range / eLocation ID:
1515 to 1523
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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