title: Gram-negative intestinal indigenous microbiota from two Siluriform fishes in a tropical reservoir.
abstract: The Gram-negative intestinal microbiota of Hypostomus auroguttatus and Pimelodus maculatus, a detritivorous and an omnivorous fish species, respectively, were compared between fishes from the reservoir and the stretch of the river below the dam of the Funil hydroelectric plant, Rio de Janeiro, Brazil. Four selective culture media were used under aerobic and two under anaerobic conditions. The omnivorous species had microbiota with higher population levels compared to the detritivorous species. The number of morphotypes and population levels of total bacteria, vibrio and Bacteroides tended to be higher in summer and autumn in the reservoir, and not different in the river. The number of morphotypes of enterobacteria and total bacteria were higher in the lotic environment compared with the lentic one. The bacteria Aeromonas hydrophila and Plesiomonas shigelloides and the obligate anaerobic Fusobacterium mortiferum were the most frequently identified microorganisms in the intestine of both H. auroguttatus and P. maculatus. Both season and habitat influenced the Gram-negative intestinal microbiota of H. auroguttatus and P. maculatus. Environmental factors influenced the Gram-negative intestinal microbiota of both species with possible impact on the interrelationship between the fishes and their digestive ecosystem, although the gut microbiota composition of fishes may result from host-specific selective pressures within the gut.
authors.affiliation: Laboratório de Ecologia de Peixes Universidade Federal Rural do Rio de Janeiro SeropédicaRJ Brazil Laboratório de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil.
authors.forename: Silvana
authors.initials: S
authors.lastname: Duarte
authors.affiliation: Departamento de Microbiologia Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo HorizonteMG Brazil Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Flávia Cristina de Paula
authors.initials: FC
authors.lastname: e Silva
authors.affiliation: Departamento de Microbiologia Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo HorizonteMG Brazil Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Danielle Alves Gomes
authors.initials: DA
authors.lastname: Zauli
authors.affiliation: Departamento de Microbiologia Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo HorizonteMG Brazil Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Jacques Robert
authors.initials: JR
authors.lastname: Nicoli
authors.affiliation: Laboratório de Ecologia de Peixes Universidade Federal Rural do Rio de Janeiro SeropédicaRJ Brazil Laboratório de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil.
authors.forename: Francisco Gerson
authors.initials: FG
authors.lastname: Araújo
mesh_terms: D000818:Animals; D058491:Bacterial Load; D001431:Bacteriological Techniques; D044822:Biodiversity; D001938:Brazil; D002397:Catfishes / Q000382:microbiology*; D006090:Gram-Negative Bacteria / Q000145:classification* / Q000302:isolation & purification*; D007422:Intestines / Q000382:microbiology*; D012621:Seasons; D014329:Tropical Climate
keywords: Hypostomus auroguttatus; Pimelodus maculatus; alimentary regimen; environment; gut microbiology