California condor microbiomes: Bacterial variety and functional properties in captive-bred individuals

PLoS One. 2019 Dec 11;14(12):e0225858. doi: 10.1371/journal.pone.0225858. eCollection 2019.

Abstract

Around the world, scavenging birds such as vultures and condors have been experiencing drastic population declines. Scavenging birds have a distinct digestive process to deal with higher amounts of bacteria in their primary diet of carcasses in varying levels of decay. These observations motivate us to present an analysis of captive and healthy California condor (Gymnogyps californianus) microbiomes to characterize a population raised together under similar conditions. Shotgun metagenomic DNA sequences were analyzed from fecal and cloacal samples of captive birds. Classification of shotgun DNA sequence data with peptide signatures using the Sequedex package provided both phylogenetic and functional profiles, as well as individually annotated reads for targeted confirmatory analysis. We observed bacterial species previously associated with birds and gut microbiomes, including both virulent and opportunistic pathogens such as Clostridium perfringens, Propionibacterium acnes, Shigella flexneri, and Fusobacterium mortiferum, common flora such as Lactobacillus johnsonii, Lactobacillus ruminus, and Bacteroides vulgatus, and mucosal microbes such as Delftia acidovorans, Stenotrophomonas maltophilia, and Corynebacterium falsnii. Classification using shotgun metagenomic reads from phylogenetic marker genes was consistent with, and more specific than, analysis based on 16S rDNA data. Classification of samples based on either phylogenetic or functional profiles of genomic fragments differentiated three types of samples: fecal, mature cloacal and immature cloacal, with immature birds having approximately 40% higher diversity of microbes.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Bacteria* / classification
  • Bacteria* / genetics
  • Bacteria* / growth & development
  • Birds / microbiology*
  • Metagenome*
  • Microbiota / physiology*

Grants and funding

The authors thank Los Alamos National Laboratory’s Laboratory Directed Research and Development Program and the Center for Space and Earth Science for the sole funding of the entirety of this study. Triad National Security, LLC, is the operator of the Los Alamos National Laboratory (LANL) under contract no. 89233218CNA000001 with the US Department of Energy. All authors, except MJ at Peregrine Fund, which was not funded, were funded by Los Alamos National Laboratory. MV and JB were at Los Alamos National Laboratory for all parts of their contribution and have current addresses included for their new work organizations. The Los Alamos National Laboratory funder provided support in the form of salaries for all authors, except MJ at the Peregrine Fund, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of all authors are articulated in the ‘author contributions’ section.