Functional changes in cecal microbiome of mallards (Anas platyrhynchos) experimentally exposed to sublethal doses of Microcystin-LR

The frequency of cyanobacterial blooms appears to have increased globally in recent decades due to human induced eutrophication and climate change. Cyanobacterial blooms can produce several groups of toxins, among which microcystin-LR (MC-LR) is one of the most abundant. Effects of MC-LR on avian microbiome have not been studied and studies in laboratory murines are limited to metabarcoding of prokaryotes. Using RNA shotgun sequencing we compared the richness and composition of metabolically active prokaryotes, expressed virulence factors, antimicrobial resistance genes, metabolic pathways, gene ontology terms, enzymes, and proteins in mallards that were orally exposed to a sublethal dose of MC-LR for one week and unexposed birds.