Bifidobacteria in Feces and Environmental Waters

The objective of this study was to identify a microbial marker for pig manure contamination. We quantified the persistence of four dominant bacterial groups from the pig intestinal tract throughout manure handling at 10 livestock operations (including aerobic digestion) by using molecular typing. The partial 16S rRNA genes of Bacteroides-Prevotella, Eubacterium-Clostridiaceae, Bacillus-Streptococcus-Lactobacillus (BSL), and Bifidobacterium group isolates were amplified and analyzed by capillary electrophoresis single-strand conformation polymorphism. The most dominant bacterial populations were identified by cloning and sequencing their 16S rRNA genes. The results showed that Bifidobacterium spp. and, to a lesser extent, members of the BSL group, were less affected by the aerobic treatment than either Eubacterium-Clostridiaceae or Bacteroides-Prevotella. Two Bifidobacterium species found in raw manure were still present in manure during land application, suggesting that they can survive outside the pig intestinal tract and also survive aerobic treatment. The 16S-23S rRNA internal transcribed spacer of one species, Bifidobacterium thermacidophilum subsp. porcinum, was sequenced, and a specific pair of primers was designed for its detection in the environment. With this nested PCR assay, this potential marker was not detected in samples from 30 bovine, 30 poultry, and 28 human fecal samples or in 15 urban wastewater effluents. As it was detected in runoff waters after spreading of pig manure, we propose this marker as a suitable microbial indicator of pig manure contamination.

Section: Discussionsupporting

confidence: 77%

Section: Discussionsupporting

confidence: 68%

Pig Manure Contamination Marker Selection Based on the Influence of Biological Treatment on the Dominant Fecal Microbial Groups

Marti¹,

Dabert²,

Pourcher³

2009

“…Some bifidobacterial species (e.g., Bifidobacterium bifidum, Bifidobacterium breve, and Bifidobacterium longum subsp. longum) are thought to be strictly of human origin, while others, such as Bifidobacterium gallinarum, Bifidobacterium angulatum, and Bifidobacterium cuniculi, appear to be exclusively associated with animal feces (21). The use of fecal material as a representation of the entire gut microbiota should be considered with caution.…”

mentioning

confidence: 99%

Exploring the Diversity of the Bifidobacterial Population in the Human Intestinal Tract

Turroni

Foroni

Pizzetti

et al. 2009

284

215

Although the health-promoting roles of bifidobacteria are widely accepted, the diversity of bifidobacteria among the human intestinal microbiota is still poorly understood. We performed a census of bifidobacterial populations from human intestinal mucosal and fecal samples by plating them on selective medium, coupled with molecular analysis of selected rRNA gene sequences (16S rRNA gene and internally transcribed spacer [ITS] 16S-23S spacer sequences) of isolated colonies. A total of 900 isolates were collected, of which 704 were shown to belong to bifidobacteria. Analyses showed that the culturable bifidobacterial population from intestinal and fecal samples include six main phylogenetic taxa, i.e., Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium adolescentis, Bifidobacterium pseudolongum, Bifidobacterium breve, and Bifidobacterium bifidum, and two species mostly detected in fecal samples, i.e., Bifidobacterium dentium and Bifidobacterium animalis subp. lactis. Analysis of bifidobacterial distribution based on age of the subject revealed that certain identified bifidobacterial species were exclusively present in the adult human gut microbiota whereas others were found to be widely distributed. We encountered significant intersubject variability and composition differences between fecal and mucosa-adherent bifidobacterial communities. In contrast, a modest diversification of bifidobacterial populations was noticed between different intestinal regions within the same individual (intrasubject variability). Notably, a small number of bifidobacterial isolates were shown to display a wide ecological distribution, thus suggesting that they possess a broad colonization capacity.

“…Nonetheless, it is possible that new bacterial targets and markers are needed for tropical and subtropical zones (46). In this regard, further phylogenetic analyses will aid in identifying new targets for method development (16). The latter analyses must be applied to other emerging source tracking targets, such as Brevibacterium spp.…”

Section: Discussionmentioning

confidence: 99%

“…Library-independent assays targeting Bacteroidetes are particu-larly promising (10,11,12), as members of this phylum make up a significantly higher portion of fecal bacteria of warm-blooded animals than FIB and, since many of them are considered obligate anaerobes, they are presumed to only survive for short periods of time after released from their hosts (13,14). Some Bacteroidales species have been shown to exhibit host specificity, and therefore, assays targeting these bacteria have been used to identify fecal sources (15,16).…”

mentioning

confidence: 99%

Tracking the Primary Sources of Fecal Pollution in a Tropical Watershed in a One-Year Study

Toledo-Hernández

Ryu

Gonzalez-Nieves

et al. 2013

A study was conducted to determine the primary sources of fecal pollution in a subtropical watershed using host-specific assays developed in temperate regions. Water samples (n ‫؍‬ 534) from 10 different sites along the Rio Grande de Arecibo (RGA) watershed were collected mostly on a weekly basis (54 sampling events) during 13 months. DNA extracts from water samples were used in PCR assays to determine the occurrence of fecal bacteria (Bacteroidales, Clostridium coccoides, and enterococci) and human-, cattle-, swine-, and chicken-specific fecal sources. Feces from 12 different animals (n ‫؍‬ 340) and wastewater treatment samples (n ‫؍‬ 16) were analyzed to determine the specificity and distribution of host-specific assays. The human-specific assay (HF183) was found to be highly specific, as it did not cross-react with nontarget samples. The cattle marker (CF128) cross-reacted to some extent with swine, chicken, and turkeys and was present in 64% of the cattle samples tested. The swine assays showed poor host specificity, while the three chicken assays showed poor host distribution. Differences in the detection of hostspecific markers were noted per site. While human and cattle assays showed moderate average detection rates throughout the watershed, areas impacted by wastewater treatment plants and cattle exhibited the highest prevalence of these markers. When conditional probability for positive signals was determined for each of the markers, the results indicated higher confidence levels for the human assay and lower levels for all the other assays. Overall, the results from this study suggest that additional assays are needed, particularly to track cattle, chicken, and swine fecal pollution sources in the RGA watershed. The results also suggest that the geographic stability of genetic markers needs to be determined prior to conducting applied source tracking studies in tropical settings. C ulturable counts of fecal indicator bacteria (FIB), such as enterococci and fecal coliforms, are used to measure fecal pollution levels in watershed systems. In order to be effective, indicators (i) should not survive for extended periods of time in the environment, (ii) should be exclusively associated with the intestinal tracts of humans and other warm-blooded animals, and (iii) should be associated with the occurrence of human enteric pathogens. However, growing evidence suggests that under some environmental conditions, FIB can survive outside the animal gut, that they are associated with a wide array of nonmammalian vertebrates and invertebrates, and that their correlation with pathogens varies significantly. Some of the evidence has been obtained from studies conducted in tropical regions (1, 2). For instance, currently used FIB can occur naturally in water accumulated in tropical epiphytic plants (3), can survive in tropical marine waters in the presence of nutrients (4), and can proliferate in tropical soils (5, 6). Studies in Mediterranean coastal areas have shown that Escherichia coli densities are often high in th...