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Abstract The role of species interactions, as well as genetic and environmental factors, all likely contribute to the composition and structure of the gut microbiome; however, disentangling these independent factors under field conditions represents a challenge for a functional understanding of gut microbial ecology. Avian brood parasites provide unique opportunities to investigate these questions, as brood parasitism results in parasite and host nestlings being raised in the same nest, by the same parents. Here we utilized obligate brood parasite brown‐headed cowbird nestlings (BHCO;Molothrus ater) raised by several different host passerine species to better understand, via 16S rRNA sequencing, the microbial ecology of brood parasitism. First, we compared faecal microbial communities of prothonotary warbler nestlings (PROW;Protonotaria citrea) that were either parasitized or non‐parasitized by BHCO and communities among BHCO nestlings from PROW nests. We found that parasitism by BHCO significantly altered both the community membership and community structure of the PROW nestling microbiota, perhaps due to the stressful nest environment generated by brood parasitism. In a second dataset, we compared faecal microbiotas from BHCO nestlings raised by six different host passerine species. Here, we found that the microbiota of BHCO nestlings was significantly influenced by the parental host species and the presence of an inter‐specific nestmate. Thus, early rearing environment is important in determining the microbiota of brood parasite nestlings and their companion nestlings. Future work may aim to understand the functional effects of this microbiota variability on nestling performance and fitness.
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Social, environmental, and developmental factors affect the microbiota of barn owls (Tyto alba) in a cross-fostering experiment
Abstract BackgroundSpecies host diverse microbial communities that can impact their digestion and health, which has led to much interest in understanding the factors that influence their microbiota. We studied the developmental, environmental, and social factors that influence the microbiota of nestling barn owls (Tyto alba) through a partial cross-fostering experiment that manipulated the social and nest environment of the nestlings. We then examined the nestling microbiota before and three weeks after the exchange of nestlings between nests, along with the microbiota of the adults at the nest and nestlings in unmanipulated nests. ResultsWe found that nestlings had higher bacterial diversity and different bacterial communities than adults. The microbiota of nestlings was more like that of their mothers than their fathers, but the similarity to the father tended to increase with the amount of time the father was in close proximity to the nest, as measured from movement data. Cross-fostered offspring had higher bacterial diversity and greater changes in bacterial community composition over time than control offspring. Cross-fostering led the microbiota of the nestlings in the experiment to converge on similar bacterial communities. The microbiota of nestling owls therefore rapidly changed along with alterations to their social and nest environments. ConclusionsThese results highlight the dynamic nature of the microbiota during early development and that social interactions can shape microbial communities.
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- Award ID(s):
- 1922560
- PAR ID:
- 10654464
- Publisher / Repository:
- Springer Science and Business Media LLC
- Date Published:
- Journal Name:
- Animal Microbiome
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2524-4671
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1186/s42523-024-00365-w
