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1.
FEMS Microbiol Ecol ; 99(12)2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-38031339

RESUMEN

Ruminants are dependent on their gut microbiomes for nutrient extraction from plant diets. However, knowledge about the composition, diversity, function, and spatial structure of gut microbiomes, especially in wild ruminants, is limited, largely because analysis has been restricted to faeces or the rumen. In two geographically separated reindeer subspecies, 16S rRNA gene amplicon sequencing revealed strong spatial structuring, and pronounced differences in microbial diversity of at least 33 phyla across the stomach, small intestine, and large intestine (including faeces). The main structural feature was the Bacteroidota to Firmicutes ratio, which declined from the stomach to the large intestine, likely reflecting functional adaptation. Metagenome shotgun sequencing also revealed highly significant structuring in the relative occurrence of carbohydrate-active enzymes (CAZymes). CAZymes were enriched in the rumen relative to the small and large intestines. Interestingly, taxonomic diversity was highest in the large intestine, suggesting an important and understudied role for this organ. Despite the two study populations being separated by an ocean and six millennia of evolutionary history, gut microbiome structuring was remarkably consistent. Our study suggests a strong selection for gut microbiome biogeography along the gastrointestinal tract in reindeer subspecies.


Asunto(s)
Microbioma Gastrointestinal , Reno , Animales , Bacterias/genética , Microbioma Gastrointestinal/genética , Tracto Gastrointestinal , Metagenoma , Reno/microbiología , ARN Ribosómico 16S/genética
2.
Sci Rep ; 11(1): 1990, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33479378

RESUMEN

The rumen microbiota comprises a community of microorganisms which specialise in the degradation of complex carbohydrates from plant-based feed. These microbes play a highly important role in ruminant nutrition and could also act as sources of industrially useful enzymes. In this study, we performed a metagenomic analysis of samples taken from the ruminal contents of cow (Bos Taurus), sheep (Ovis aries), reindeer (Rangifer tarandus) and red deer (Cervus elaphus). We constructed 391 metagenome-assembled genomes originating from 16 microbial phyla. We compared our genomes to other publically available microbial genomes and found that they contained 279 novel species. We also found significant differences between the microbiota of different ruminant species in terms of the abundance of microbial taxonomies, carbohydrate-active enzyme genes and KEGG orthologs. We present a dataset of rumen-derived genomes which in combination with other publicly-available rumen genomes can be used as a reference dataset in future metagenomic studies.


Asunto(s)
Bacterias/genética , Microbiota/genética , Rumen/microbiología , Rumiantes/genética , Alimentación Animal , Animales , Bacterias/clasificación , Bovinos , Ciervos/genética , Ciervos/microbiología , Metagenómica , Reno/genética , Reno/microbiología , Rumiantes/clasificación , Ovinos/genética , Ovinos/microbiología
3.
Ecohealth ; 17(1): 174-180, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32006181

RESUMEN

A 2016 outbreak of anthrax on the Yamal Peninsula in Siberia that led to the culling of more than two hundred thousand reindeer and killed one human, resulted in significant media interests and in the reporting was often linked to thawing permafrost and ultimately climate change. Here, we review the historic context of anthrax outbreaks in the circumpolar North and explore alternative explanations for the anthrax outbreak in Western Siberia. Further, we propose a convergence model where multiple factors likely contributed to the outbreak of anthrax, including an expanded population and discontinued vaccination.


Asunto(s)
Carbunco/epidemiología , Animales , Carbunco/veterinaria , Regiones Árticas/epidemiología , Bacillus anthracis , Cambio Climático , Brotes de Enfermedades , Humanos , Reno/microbiología , Siberia , Vacunación
4.
PLoS One ; 15(1): e0227819, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31935269

RESUMEN

The foods we eat contain microorganisms that we ingest alongside the food. Industrialized food systems offer great advantages from a safety point of view, but have also been accused of depleting the diversity of the human microbiota with negative implications for human health. In contrast, artisanal traditional foods are potential sources of a diverse food microbiota. Traditional foods of the Greenlandic Inuit are comprised of animal-sourced foods prepared in the natural environment and are often consumed raw. These foods, some of which are on the verge of extinction, have not previously been microbiologically characterized. We mapped the microbiota of foods stemming from traditional Inuit land-based hunting activities. The foods included in the current study are dried muskox and caribou meat, caribou rumen and intestinal content as well as larval parasites from caribou hides, all traditional Inuit foods. This study shows that traditional drying methods are efficient for limiting microbial growth through desiccation. The results also show the rumen content of the caribou to be a highly diverse source of microbes with potential for degradation of plants. Finally, a number of parasites were shown to be included in the biodiversity of the assessed traditional foods. Taken together, the results map out a diverse source of ingested microbes and parasites that originate from the natural environment. These results have implications for understanding the nature-sourced traditional Inuit diet, which is in contrast to current day diet recommendations as well as modern industrialized food systems.


Asunto(s)
Dieta , Manipulación de Alimentos , Inuk , Carne/microbiología , Animales , Animales Salvajes/microbiología , Microbiología de Alimentos , Groenlandia , Humanos , Reno/microbiología , Rumiantes/microbiología
5.
J Wildl Dis ; 55(3): 733-736, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30768915

RESUMEN

Mycoplasma ovipneumoniae has been reported in association with respiratory disease in the wild only in members of the subfamily Caprinae of the family Bovidae. We identified M. ovipneumoniae in a cervid: a free-ranging barren ground caribou (Rangifer tarandus granti) yearling with polymicrobial bronchopneumonia.


Asunto(s)
Infecciones por Mycoplasma/veterinaria , Mycoplasma ovipneumoniae , Neumonía Bacteriana/veterinaria , Reno/microbiología , Alaska , Animales , Resultado Fatal , Femenino , Infecciones por Mycoplasma/microbiología , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/patología
7.
BMC Vet Res ; 14(1): 15, 2018 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-29338721

RESUMEN

BACKGROUND: Infectious keratoconjunctivitis (IKC) is one of the most common ocular diseases in ruminants worldwide. In addition to keratitis and conjunctivitis, animals with IKC can develop uveitis, corneal ulcer, and in severe cases, blindness. The bacteria Moraxella spp. has been described as the primary causative agent of infectious bovine keratoconjunctivitis (IBK) in cattle (Bos taurus), while Chlamydia spp. and Mycoplasma conjunctivae are considered the main causative agents of IKC in sheep (Ovis aries). Previous studies indicated cervid herpesvirus 2 (CvHV2) as the primary causative agent of IKC in semi-domesticated reindeer (Rangifer tarandus tarandus). The aim of the study was to investigate the presence and prevalence of potential pathogens for IKC in reindeer, and compare the ocular microbiota of animals with IKC, with apparently healthy animals. RESULTS: Semi-domesticated reindeer (n = 341), with (n = 108) or without (n = 113) ocular clinical signs, or with no information on clinical status (n = 120), were sampled in Norway, Sweden and Finland in 2010-2014. Seroprevalence was 37.4% for alphaherpesvirus (95/254), 3.8% for gammaherpesvirus (8/211) and 7.1% for pestivirus (15/211) (ELISA). PCR analyses of conjunctival swab samples revealed a prevalence of 28.5% for CvHV2 (57/200), 11.9% for Chlamydiaceae (16/135) and 1.0% for M. conjunctivae (2/197). Bacteriological cultivation of 202 conjunctival swab samples revealed bacterial growth from 75.2% of the samples, with Moraxella spp. being isolated from 21.6% (11/51) of the animals with and 5.6% (5/84) without ocular clinical signs. A significant association (p < 0.001) existed between the presence of clinical signs of IKC and CvHV2 DNA in the affected eyes, an association that was not present for other microorganisms. CONCLUSIONS: These results support the hypothesis that CvHV2 is the primary agent of IKC in semi-domesticated reindeer in Fennoscandia, with Moraxella bovoculi being a secondary candidate, since it was isolated in two different outbreaks of IKC. Further studies should be carried out to better understand the infection biology and the pathogenesis of IKC in reindeer.


Asunto(s)
Infecciones por Herpesviridae/veterinaria , Queratoconjuntivitis Infecciosa/microbiología , Queratoconjuntivitis Infecciosa/virología , Reno/virología , Varicellovirus/aislamiento & purificación , Animales , Ojo/microbiología , Microbiota , Moraxella/aislamiento & purificación , Infecciones por Moraxellaceae/veterinaria , Reno/microbiología , Países Escandinavos y Nórdicos/epidemiología , Estudios Seroepidemiológicos
8.
PLoS One ; 12(3): e0172669, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28328953

RESUMEN

Lichens form a critical portion of barren ground caribou (Rangifer tarandus groenlandicus) diets, especially during winter months. Here, we assess lichen mat volume across five herd ranges in the Northwest Territories and Nunavut, Canada, using newly developed composite Landsat imagery. The lichen volume estimator (LVE) was adapted for use across 700 000 km2 of barren ground caribou habitat annually from 1984-2012. We subsequently assessed how LVE changed temporally throughout the time series for each pixel using Theil-Sen's slopes, and spatially by assessing whether slope values were centered in local clusters of similar values. Additionally, we assessed how LVE estimates resulted in changes in barren ground caribou movement rates using an extensive telemetry data set from 2006-2011. The Ahiak/Beverly herd had the largest overall increase in LVE (median = 0.033), while the more western herds had the least (median slopes below zero in all cases). LVE slope pixels were arranged in significant clusters across the study area, with the Cape Bathurst, Bathurst, and Bluenose East herds having the most significant clusters of negative slopes (more than 20% of vegetated land in each case). The Ahiak/Beverly and Bluenose West had the most significant positive clusters (16.3% and 18.5% of vegetated land respectively). Barren ground caribou displayed complex reactions to changing lichen conditions depending on season; the majority of detected associations with movement data agreed with current understanding of barren ground caribou foraging behavior (the exception was an increase in movement velocity at high lichen volume estimates in Fall). The temporal assessment of LVE identified areas where shifts in ecological conditions may have resulted in changing lichen mat conditions, while assessing the slope estimates for clustering identified zones beyond the pixel scale where forage conditions may be changing. Lichen volume estimates associated with barren ground caribou movement metrics in an expected manner and, as such, show value for future habitat assessments.


Asunto(s)
Líquenes/crecimiento & desarrollo , Reno/microbiología , Reno/fisiología , Animales , Ecosistema , Modelos Biológicos , Movimiento/fisiología , Territorios del Noroeste , Nunavut , Estaciones del Año
9.
J Food Prot ; 80(3): 454-458, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28207302

RESUMEN

Fecal samples collected from 470 slaughtered reindeer 6 to 7 months of age were screened by real-time PCR (after enrichment) for Shiga toxin genes (stx) and then for Escherichia coli serogroup O157. Shiga toxin genes were found frequently (>30% of samples), and serogroup O157 was detected in 20% of the stx-positive samples. From these samples, a total of 25 E. coli O157:H- isolates (nonmotile but PCR positive for fliCH7) were obtained. Twenty-four of these E. coli O157:H- isolates did not ferment sorbitol and originated from one geographic area. These 24 isolates belonged to the multilocus sequence type 11, typical for Shiga toxin-producing E. coli (STEC) O157:H7 and O157:H-, and harbored genes stx1a, stx2c, eae, and hlyA; the stx2c subtype has been associated with high virulence. In contrast, one E. coli O157:H- isolate (multilocus sequence type 11) did ferment sorbitol, lacked Shiga toxin genes, but was positive for eae, hlyA, and sfpA. This isolate closely resembled an STEC that has lost its Shiga toxin genes. Additional examination revealed that reindeer can be colonized by various other STEC isolates; 21 non-O157 STEC isolates belonged to four multilocus sequence types, harbored stx1a (8 isolates) or stx2b (13 isolates), and in the stx2b-positive isolates the recently described new allelic variants (subAB2-2 and subAB2-3) for subtilase cytotoxin were identified. Hence, slaughtered semidomesticated Finnish reindeer might constitute a little known reservoir for STEC O157:H7/H- and other serogroups, and the risk of direct or indirect transmission of these pathogens from reindeer to humans and domestic livestock must not be overlooked.


Asunto(s)
Escherichia coli/genética , Reno/microbiología , Escherichia coli Shiga-Toxigénica/clasificación , Adhesinas Bacterianas/genética , Animales , Infecciones por Escherichia coli/veterinaria , Escherichia coli O157/genética , Proteínas de Escherichia coli/genética , Heces , Finlandia , Humanos
10.
PLoS One ; 11(5): e0155213, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27159387

RESUMEN

Reindeer (Rangifer tarandus tarandus) are large Holarctic herbivores whose heterogeneous diet has led to the development of a unique gastrointestinal microbiota, essential for the digestion of arctic flora, which may include a large proportion of lichens during winter. Lichens are rich in plant secondary metabolites, which may affect members of the gut microbial consortium, such as the methane-producing methanogenic archaea. Little is known about the effect of lichen consumption on the rumen and cecum microbiotas and how this may affect methanogenesis in reindeer. Here, we examined the effects of dietary lichens on the reindeer gut microbiota, especially methanogens. Samples from the rumen and cecum were collected from two groups of reindeer, fed either lichens (Ld: n = 4), or a standard pelleted feed (Pd: n = 3). Microbial densities (methanogens, bacteria and protozoa) were quantified using quantitative real-time PCR and methanogen and bacterial diversities were determined by 454 pyrosequencing of the 16S rRNA genes. In general, the density of methanogens were not significantly affected (p>0.05) by the intake of lichens. Methanobrevibacter constituted the main archaeal genus (>95% of reads), with Mbr. thaueri CW as the dominant species in both groups of reindeer. Bacteria belonging to the uncharacterized Ruminococcaceae and the genus Prevotella were the dominant phylotypes in the rumen and cecum, in both diets (ranging between 16-38% total sequences). Bacteria belonging to the genus Ruminococcus (3.5% to 0.6%; p = 0.001) and uncharacterized phylotypes within the order Bacteroidales (8.4% to 1.3%; p = 0.027), were significantly decreased in the rumen of lichen-fed reindeer, but not in the cecum (p = 0.2 and p = 0.087, respectively). UniFrac-based analyses showed archaeal and bacterial libraries were significantly different between diets, in both the cecum and the rumen (vegan::Adonis: pseudo-F<0.05). Based upon previous literature, we suggest that the altered methanogen and bacterial profiles may account for expected lower methane emissions from lichen-fed reindeer.


Asunto(s)
Ciego/microbiología , Dieta , Líquenes , Metano/metabolismo , Microbiota , Reno/fisiología , Rumen/microbiología , Animales , Archaea/genética , Bacterias/clasificación , Bacterias/genética , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reno/microbiología
11.
Parasit Vectors ; 8: 526, 2015 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-26458271

RESUMEN

BACKGROUND: Enterocytozoon bieneusi is the most common pathogen of 14 microsporidian species infecting humans worldwide. In China, E. bieneusi has been reported in some common livestock and environmental specimens. However, no information is available on occurrence of E. bieneusi in reindeers. The objective of the present study was to detect and genotype E. bieneusi in reindeers in China, and assess the zoonotic potential. FINDINGS: 125 fecal specimens were collected from wild reindeers in the northeast forest region of Great Hinggan Mountains of China. By PCR and sequencing of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene of E. bieneusi, an average infection rate of 16.8 % (21/125) was observed in reindeers. E. bieneusi was detected in two age groups: 7.7 % (3/39) in the youths (aged 1 to 2 years) and 22.2 % (18/81) in the adults (aged 3 to 8 years). Five genotypes were identified: one known genotype Peru6 (n = 6) and four novel genotypes named as CHN-RD1 (n = 12), and CHN-RD 2 to CHN-RD4 (one each). In phylogenetic analysis, all the novel genotypes together with known genotype Peru 6 were clustered into group 1. CONCLUSIONS: This is the first report of E. bieneusi infection in reindeers, expanding the host range of E. bieneusi. The fact of genotype Peru 6 previously reported in humans and the result of all the novel genotypes falling into zoonotic group 1 suggest the possibility of E. bieneusi transmitted from reindeers to humans.


Asunto(s)
Enterocytozoon/aislamiento & purificación , Microsporidiosis/epidemiología , Reno/microbiología , Animales , Secuencia de Bases , China/epidemiología , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Enterocytozoon/clasificación , Enterocytozoon/genética , Femenino , Genotipo , Especificidad del Huésped , Humanos , Masculino , Microsporidiosis/microbiología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Zoonosis
12.
Microb Ecol ; 66(4): 840-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23959114

RESUMEN

Highly cellulolytic bacterial species such as Ruminococcus flavefaciens are regarded essential for the microbial breakdown of cellulose in the rumen. We have investigated the effect of ruminal dosing of R. flavefaciens strain 8/94-32 during realimentation of starved reindeer (males, n = 3). Microbiome function measured as in situ digestion of cellulose and food pellets (percent DMD; dry matter disappearance) decreased after probiotic dosing. Microbial community analyses (>100,000 16S rDNA gene sequences for 27 samples) demonstrated that ruminal dosing influenced the microbiome structure; reflected by increased phylogenetic distances from background samples (unweighted UniFrac analysis) and reduced species diversity and evenness. Despite the inability to detect strain 8/94-32 post-dosing, the relative abundance of its affiliate family Ruminococcaceae remained consistent throughout the trial, whilst a dominant peak in the genus Prevotella and decline in uncharacterized Bacteroidetes (uBacNR) were observed in treatment samples. No clear relationships were observed between the relative abundance of Ruminococcaceae, Prevotella and uBacNR with cellulose DMD; however, Prevotella (negative) and uBacNR (positive) exhibited relationships with pellet DMD. These unexpected effects of ruminal dosing of a cellulolytic bacterium on digestibility are relevant for other studies on rumen manipulation.


Asunto(s)
Bacterias/aislamiento & purificación , Microbiota , Probióticos/administración & dosificación , Rumen/microbiología , Ruminococcus/fisiología , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Biodiversidad , Celulosa/metabolismo , Digestión , Masculino , Datos de Secuencia Molecular , Filogenia , Reno/metabolismo , Reno/microbiología , Rumen/metabolismo
13.
Epidemiol Infect ; 141(7): 1545-51, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23298678

RESUMEN

We investigated the presence of Mycobacterium spp. in livestock in northern China. Of the 163 clinical samples selected for this study, 20 were from throat swabs of dairy cows, and 143 were tissue samples (including lung tissue from one reindeer, hilar lymph node tissue from 55 cows, and liver tissue from 87 sheep). A total of 41 mycobacterial isolates were identified including two isolates of M. caprae and 39 non-tuberculous mycobacteria (NTM) isolates. Multi-locus variable-number tandem repeat analysis (MLVA) profiles of the two M. caprae isolates proved to be unique. This is the first report of M. caprae isolates from livestock in China. This study also confirms previous reports that NTM is common in livestock in northern China.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Infecciones por Mycobacterium no Tuberculosas/veterinaria , Micobacterias no Tuberculosas/aislamiento & purificación , Reno/microbiología , Enfermedades de las Ovejas/epidemiología , Animales , Técnicas de Tipificación Bacteriana , Bovinos , Enfermedades de los Bovinos/diagnóstico , China/epidemiología , ADN Bacteriano/análisis , Femenino , Tipificación de Secuencias Multilocus , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Micobacterias no Tuberculosas/clasificación , Micobacterias no Tuberculosas/genética , Filogenia , Reacción en Cadena de la Polimerasa , Ovinos , Enfermedades de las Ovejas/diagnóstico
14.
J Comp Pathol ; 149(1): 126-31, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23290384

RESUMEN

This report describes an unusual presentation of paratuberculosis in a captive, 4-year-old female tundra reindeer (Rangifer tarandus tarandus). The gross and histological presentation was consistent with clinical paratuberculosis as previously reported for other ruminants, with poor body condition, subcutaneous oedema, granulomatous ileitis (multibacillary), mesenteric lymphadenitis and hepatitis. However, this animal also presented with unusual lung lesions, with necrosis and mineralization similar to that reported for Mycobacterium bovis in other wild and domestic ruminants. The presence of DNA of Mycobacterium avium subsp. paratuberculosis was confirmed by polymerase chain reaction (PCR) in intestine and lung tissue (IS900, Hsp65) and PCR tests for the detection of Mycobacterium tuberculosis complex and other members of the M. avium complex were negative.


Asunto(s)
Pulmón/microbiología , Pulmón/patología , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/patología , Reno/microbiología , Animales , Femenino
15.
Mol Gen Mikrobiol Virusol ; (4): 28-33, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-23248850

RESUMEN

GOAL: Comparative molecular-genetic characterization of Brucella isolates from dogs and reindeers in Russia by molecular-genetic typing methods. MATERIALS AND METHODS: 19 canine and 2 rangiferine Brucella isolates were studied by molecular typing methods based on PCR for differential species and biovar specific molecular targets and MLVA (multiple locus variable number tandem repeats analysis) using primers to 12 known variable loci. RESULTS: Using PCR for differential molecular targets, canine Brucella isolates were characterized as B. canis and rangiferine isolates as B. suis biovar 4. MLVA revealed 5 identical and 7 variable MLVA loci. Using the dendrogram. all the isolates on the data of 12 loci were classified into the close related cluster. On the other hand, high discrimination power of MLVA with a resulting Hunter and Gaston discriminatory index (HGDI) of 0.9842 was shown to reveal genetic diversity for the isolates of 17 MLVA genotypes. CONCLUSION: B. canis and B. suis isolates from different geographical regions in Russia were genetically close related, thereby confirming known genetic relationship between these species. Related MLVA genotypes of isolates were connected to certain regions of preliminary isolation in Russia. To improve the system ofbrucellosis surveillance in Russia MLVA typing of more canine and rangiferine Brucella isolates having epidemiological danger for humans is required to be studied.


Asunto(s)
Brucella , Brucelosis/genética , Reno/microbiología , Animales , Técnicas de Tipificación Bacteriana/métodos , Brucella/genética , Brucella/aislamiento & purificación , Brucelosis/epidemiología , Brucelosis/microbiología , Brucelosis/veterinaria , Perros , Humanos , Reacción en Cadena de la Polimerasa/métodos , Reno/genética , Federación de Rusia/epidemiología
16.
J Wildl Dis ; 48(4): 918-24, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23060493

RESUMEN

Mycobacterium avium subspecies paratuberculosis (MAP) is a common pathogen in domestic ruminants that causes granulomatous inflammation of the small intestine leading to emaciation and wasting. Clinical disease (Johne's disease) is also reported for several wild ruminant species. Between 2007 and 2009 we collected 561 fecal samples from caribou (Rangifer tarandus ssp.) representing 10 herds of migratory caribou, two herds of caribou from Greenland, and three populations of boreal woodland caribou. Feces were tested for MAP by bacterial culture and PCR targeting the IS900 insertion sequence. In total, 31 samples from eight different populations representing all three ecotypes were found positive for MAP by PCR, with one sample from the Rivière-aux-Feuilles herd also being culture positive for the type II (cattle) strain. The proportion of positive animals was particularly high in the Akia-Maniitsoq herd in Greenland, and Rivière-aux-Feuilles and Riviè re-George herds in northeastern Canada (23.4, 11.5, and 10.0%, respectively). Our results indicate that MAP is present in several caribou herds of different ecotypes in northern Canada and Greenland and that MAP circulates within wildlife populations that do not have ongoing contact with domestic livestock. The epidemiology, pathogenicity, and effects on the health of caribou in northern ecosystems remain unknown.


Asunto(s)
Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis/epidemiología , Reno/microbiología , Animales , Animales Salvajes/microbiología , Canadá/epidemiología , Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/veterinaria , Heces/microbiología , Femenino , Groenlandia/epidemiología , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Vigilancia de Guardia/veterinaria
17.
PLoS One ; 7(6): e38571, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22701672

RESUMEN

Lignocellulosic biomass remains a largely untapped source of renewable energy predominantly due to its recalcitrance and an incomplete understanding of how this is overcome in nature. We present here a compositional and comparative analysis of metagenomic data pertaining to a natural biomass-converting ecosystem adapted to austere arctic nutritional conditions, namely the rumen microbiome of Svalbard reindeer (Rangifer tarandus platyrhynchus). Community analysis showed that deeply-branched cellulolytic lineages affiliated to the Bacteroidetes and Firmicutes are dominant, whilst sequence binning methods facilitated the assemblage of metagenomic sequence for a dominant and novel Bacteroidales clade (SRM-1). Analysis of unassembled metagenomic sequence as well as metabolic reconstruction of SRM-1 revealed the presence of multiple polysaccharide utilization loci-like systems (PULs) as well as members of more than 20 glycoside hydrolase and other carbohydrate-active enzyme families targeting various polysaccharides including cellulose, xylan and pectin. Functional screening of cloned metagenome fragments revealed high cellulolytic activity and an abundance of PULs that are rich in endoglucanases (GH5) but devoid of other common enzymes thought to be involved in cellulose degradation. Combining these results with known and partly re-evaluated metagenomic data strongly indicates that much like the human distal gut, the digestive system of herbivores harbours high numbers of deeply branched and as-yet uncultured members of the Bacteroidetes that depend on PUL-like systems for plant biomass degradation.


Asunto(s)
Bacteroidetes/genética , Bacterias Grampositivas/genética , Metagenoma/genética , Filogenia , Reno/microbiología , Rumen/microbiología , Animales , Regiones Árticas , Secuencia de Bases , Celulosa/metabolismo , Clonación Molecular , Cartilla de ADN/genética , Femenino , Sitios Genéticos/genética , Bacterias Grampositivas/metabolismo , Funciones de Verosimilitud , Metagenómica/métodos , Modelos Genéticos , Datos de Secuencia Molecular , Noruega , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
18.
Benef Microbes ; 2(1): 47-55, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21831789

RESUMEN

The cellulolytic Ruminococcus flavefaciens has previously been introduced into the ruminant rumen to increase microbial degradation of plant cell wall carbohydrates. The functional effect of an introduced bacterium depends on its ability to establish in the digestive tract, and signature probes can be used as a tool to track and quantify introduced strains. The purpose of this current study was to develop an oligonucleotide signature probe targeting the 16S-23S rRNA internal transcribed spacer (ITS) of a putative probiotic cellulolytic isolate (R. flavefaciens strain 8/94-32) from the rumen of reindeer (Rangifer tarandus tarandus). The 16S-23S rRNA gene ITS of three Ruminococcus strains; R. flavefaciens strain 8/94-32, R. flavefaciens FD-1 and Ruminococcus albus Ra-8, was investigated. The ITS region has been reported to vary more between closely related bacteria compared to the widely used 16S rRNA gene, and a high degree of sequence polymorphism was indeed detected between the three Ruminococcus strains studied. Based on observed sequence differences, two oligonucloetide probes, ITSRumi1 and ITSRumi2, targeting the ITS region of the R. flavefaciens isolate 8/94-32 were developed. Probe specificity was evaluated in dot blot hybridisations with R. flavefaciens isolate 8/94-32 and four other Ruminococcus-strains tested. The probe ITSRumi1 gave positive signals for the R. flavefaciens isolate 8/94-32 only, while probe ITSRumi2 gave positive signals for R. flavefaciens isolate 8/94-32 as well as for R. albus Ra-8. The result of hybridisations with the probe ITSRumi1 indicates that the probe is specific for the R. flavefaciens strain 8/94-32 amongst the four Ruminococcus-strains tested, and is promising for further studies using it as a signature probe for tracking this strain when re-introduced to the reindeer rumen.


Asunto(s)
Reno/microbiología , Rumen/microbiología , Ruminococcus/genética , Animales , Variación Genética , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Probióticos/aislamiento & purificación , ARN Ribosómico/genética , Ruminococcus/aislamiento & purificación , Análisis de Secuencia de ARN
19.
Can J Microbiol ; 57(7): 617-21, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21774627

RESUMEN

Strains of Butyrivibrio are principal cellulytic bacteria in the rumen of the High Arctic Svalbard reindeer ( Rangifer tarandus platyrhynchus ). According to phylogenetic analysis based on 16S rRNA gene sequencing, Butyrivibrio can be divided into three subgroups within the Clostridia class of the phylum Firmicutes, but the current phenotypic and genotypic differentiation within the family Lachnospiraceae is insufficient. This current study describes the sequence diversity of the 16S-23S rRNA intergenic transcribed spacer (ITS) region of Butyrivibrio isolates from reindeer. A total of 17 different ITS sequences with sizes between 449 and 784 nt were obtained. Genes encoding tRNA(Ile) and tRNA(Ala) were identified in four of the sequences. Phylogenetic neighbor-joining trees were constructed based on the ITS sequence and compared with a phylogenetic neighbor-joining tree based on 16S rRNA gene sequences previously obtained for the same isolates. These comparisons indicated a better differentiation between strains in the ITS sequence than the 16S rRNA gene based tree. Through this study, a better means for identifying and tracking fibrolytic and potentially probiotic Butyrivibrio strains in reindeer and other ruminants has been provided.


Asunto(s)
Butyrivibrio/clasificación , ADN Espaciador Ribosómico/química , Variación Genética , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Reno/microbiología , Animales , Butyrivibrio/genética , Butyrivibrio/aislamiento & purificación , Genes de ARNr , Filogenia , ARN de Transferencia/genética , Rumen/microbiología
20.
Naturwissenschaften ; 97(3): 273-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20033122

RESUMEN

Reindeer (Rangifer tarandus) eat and utilize lichens as an important source of energy and nutrients in winter. Lichens synthesize and accumulate a wide variety of phenolic secondary compounds, such as usnic acid, as a defense against herbivores and to protect against damage by UV-light in solar radiation. We have examined where and to what extent these phenolic compounds are degraded in the digestive tract of the reindeer, with particular focus on usnic acid. Three male reindeer were given ad libitum access to a control diet containing no usnic acid for three weeks and then fed lichens ad libitum (primarily Cladonia stellaris) containing 9.1 mg/g DM usnic acid for 4 weeks. Usnic acid intake in reindeer on the lichen diet was 91-117 mg/kg BM/day. In spite of this, no trace of usnic acid or conjugates of usnic acid was found either in fresh rumen fluid, urine, or feces. This suggests that usnic acid is rapidly degraded by rumen microbes, and that it consequently is not absorbed by the animal. This apparent ability to detoxify lichen phenolic compounds may gain increased importance with future enhanced UV-B radiation expected to cause increased protective usnic acid/phenol production in lichens.


Asunto(s)
Benzofuranos/metabolismo , Reno/fisiología , Rumen/microbiología , Alimentación Animal , Animales , Benzofuranos/análisis , Benzofuranos/orina , Ciego/metabolismo , Colon/metabolismo , Digestión/fisiología , Ecosistema , Heces/química , Tracto Gastrointestinal/metabolismo , Intestino Delgado/metabolismo , Riñón/metabolismo , Líquenes/metabolismo , Hígado/metabolismo , Masculino , Noruega , Reno/microbiología , Rumen/metabolismo , Rayos Ultravioleta
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