Biology subjects

Baillargeon, T.

Publications and source records attributed to Baillargeon, T..

2 recordsLinked to original sources

bioRxiv2024

Birds affected by a 2021 avian mortality event are strongly associated with supplemental feeding and ground foraging behaviors

In 2021, news outlets and state natural resources agencies reported a large number of avian deaths across several states in the eastern and midwestern USA. This event fomented a rapid and robust response from animal health experts from across the country. Given the clustered pattern of disease and death, an infectious etiology was rigorously investigated. No single causative pathogen was identified, leaving the cause and thus epidemiology of the mortality event unex-plained. In this study, we attempted to hone in on potential causes or contributors to this event by constructing a dataset on affected birds life history, phylogeny, and ecology. After a preliminary analysis of these features, we developed a statistical pipeline to test two hypotheses regarding features of birds associated with the mortality event: (1) that a significant proportion of affected birds in the total sample are members of the Cornell Feederwatch list (i.e., birds that consume supplemental feed, and their predators), and that (2) ground-feeding species would be significantly represented in the sample. While logistic regression models support the plausibility of the two hypotheses, they are statistically indistinguishable. We discuss the implications of these findings, propose future work, and highlight the importance of ecological and behavioral expertise in understanding epidemiological phenomena.

ecology↗

bioRxiv2023

Metagenomics for pathogen detection during a wildlife mortality event in songbirds

Mass mortality events in wildlife can be indications of an emerging infectious disease. During the spring and summer of 2021, hundreds of dead passerines were reported across the eastern US. Birds exhibited a range of clinical signs including swollen conjunctiva, ocular discharge, ataxia, and nystagmus. As part of the diagnostic investigation, high-throughput metagenomic next-generation sequencing was performed across three molecular laboratories on samples from affected birds. Many potentially pathogenic microbes were detected, with bacteria comprising the largest proportion; however, no singular agent was consistently identified, with many of the detected microbes also found in unaffected (control) birds, and thus considered to be subclinical infections. Congruent results across laboratories have helped drive further investigation into alternative causes including environmental contaminants and nutritional deficiencies. This work highlights the utility of metagenomic approaches in investigations of emerging diseases and provides a framework for future wildlife mortality events. Article Summary LineThe causative agent of a mass mortality event in passerines remains inconclusive after metagenomic high-throughput sequencing with results prompting further investigation into non-pathogenic causes.

genomics↗