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Cattle Faeces (cattle + faeces)
Selected AbstractsEnterococcus faecalis with the gelatinase phenotype regulated by the fsr operon and with biofilm-forming capacity are common in the agricultural environmentENVIRONMENTAL MICROBIOLOGY, Issue 6 2009Lilia Macovei Summary The prevalence of gelatinase activity and biofilm formation among environmental enterococci was assessed. In total, 396 enterococcal isolates from swine and cattle faeces and house flies from a cattle farm were screened for gelatinase activity. The most prevalent phenotype on Todd,Hewitt agar with 1.5% skim milk was the weak protease (WP) (72.2% of isolates), followed by the strong protease (SP) 18.7%, and no protease (NP) (9.1%). The majority of WP isolates was represented by Enterococcus hirae (56.9%), followed by Enterococcus faecium (25.9%), Enterococcus casseliflavus (10.4%), Enterococcus gallinarum (5.2%) and Enterococcus saccharolyticus (1.7%). All WP isolates were negative for gelE (gelatinase) and sprE (serine protease) as well as the fsrABDC operon that regulates the two proteases, and only four isolates (7.0%) formed biofilms in vitro. All SP isolates were Enterococcus faecalis positive for the fsrABDC, gelE, sprE genes and the majority (91.2%) formed a biofilm. Diversity of NP isolates was relatively evenly distributed among E. hirae, E. faecium, E. casseliflavus, E. gallinarum, Enterococcus durans, E. saccharolyticus and Enterococcus mundtii. All NP isolates were negative for the fsr operon and only four E. hirae (11.1%) formed a biofilm. Of further interest was the loss of the gelatinase phenotype (18.9% of isolates) from SP isolates after 4 month storage at 4,8°C and several passages of subculture. Results of reverse transcription PCR analysis indicated that mRNA was produced for all the genes in the frs operon and sequencing of the gelE gene did not reveal any significant mutations. However, gelatinase was not detectable by Western blot analysis. Our study shows that E. faecalis with the complete fsr operon and the potential to form a biofilm are relatively common in the agricultural environment and may represent a source/reservoir of clinically relevant strains. In addition, many environmental enterococci, especially E. hirae, produce an unknown WP that can hydrolyse casein but does not contribute to biofilm formation. The stability of the gelatinase phenotype in E. faecalis and its regulation will require additional studies. [source] Quantitative PCR assays to survey the bovine adenovirus levels in environmental samplesJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2010K. Wong Abstract Aims:, Previous studies suggested bovine adenoviruses (BAdVs) could be used as cattle faecal indicators. The main aim of this study was to survey the levels of BAdV in environmental samples using quantitative polymerase chain reaction (qPCR). Methods and Results:, Two qPCR assays were developed to identify and quantify BAdVs in environmental samples. BAdVs were detected in all dairy manure, and in most cases, the sample concentrations were around 103,104 copies ml,1. Farm tile drainage samples were also detected, but the concentrations were about 1,3 log10 lower than the BAdV concentrations in the manure samples. The genome equivalent copy (GEC) levels of BAdV and the phage forming unit (PFU) levels of somatic phage in manure samples were comparable. Four of twenty individual cattle faeces were positive with concentrations similar to that found in the manure samples. Sequencing results confirmed the presence of BAdV in the environmental samples, and phylogenetic analysis indicated that BAdV 2 and 4 were the most prevalent serotypes in all the manure samples tested. The qPCR assays developed in this study showed higher sensitivity in detecting BAdV 1 and 2 than the previous published nested assay. Conclusion:, The high levels of BAdV in the environmental samples may suggest it could be used for bovine faecal indicator. The significant levels of BAdV in the drainage samples may indicate the potential of surface water pollution by the manure applied to farm fields. Significance and Impact of the Study:, This is the first study that reports the quantitative level of BAdV in environmental samples. These results could be useful when it comes to determining whether BAdV could be utilized as a bovine faecal indicator. [source] Diversity of Escherichia coli O157 in a longitudinal farm study using multiple-locus variable-number tandem-repeat analysisJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2008A.M. Urdahl Abstract Aims:, To perform a longitudinal study of the diversity of Escherichia coli O157 from a ruminant pasture/stream environment using multiple-locus variable-number tandem-repeat analysis (MLVA). Methods and Results:, Samples of faecal droppings from grazing ruminants and from an adjacent stream were tested longitudinally for E. coli O157 by enrichment and immunomagnetic separation (IMS). Using MLVA, 24 different profiles were identified from a total of 231 E. coli O157 isolates, of which 80 were included in a similarity analysis. Four main clusters with several subclusters were observed. Although there was close contact between sheep and cattle during the study period, E. coli O157 was surprisingly not detected from cattle faeces. Conclusions:, The cluster analysis indicated both unrelated and closely related E. coli O157 strains. The choice of loci to target in MLVA is important for the subtyping result, as loci with high diversities are essential for discriminating between closely related isolates. Significance and Impact of the Study:, There is a lack of data available on the use of MLVA to describe E. coli O157 diversity and changes over time in the animal reservoirs and the environment. Such data are needed in order to further develop MLVA as a typing method. [source] Leaching of bioluminescent Escherichia coli O157:H7 from sheep and cattle faeces during simulated rainstorm eventsJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2008A.P. Williams Abstract Aims:, Development of a novel inoculation technique to improve the current methods of determining the leaching of Escherichia coli O157:H7 from faeces. Methods and Results:, Ruminant faeces were inoculated with a high [c. 107 colony forming units (CFU) g,1] or low (c. 104 CFU g,1) load of a lux- marked strain of E. coli O157:H7 via injection, and subjected to four simulated heavy rainfall events. The population density and metabolic activity of E. coli O157:H7 recovered within the leachate was determined following each simulated rain event and compared with the indigenous E. coli population. The concentration of E. coli O157:H7 in the leachates followed a similar trend to that of nonpathogenic E. coli. Significantly greater densities of generic and pathogenic E. coli were recovered in the leachates generated from sheep faeces compared with cattle faeces. Pathogen metabolic activity was also significantly greater in sheep faeces. Conclusions:, Our findings show that E. coli O157:H7 may readily leach from ruminant faeces during rain events. The bacterium leaches more freely from sheep faeces than from cattle faeces and displays greater metabolic activity within sheep leachate. Significance and Impact of the Study:, A novel inoculation technique was developed that allowed the determination of both population density and cellular activity of E. coli O157:H7 in leachate derived from faeces. [source] Effect of finishing diets on Escherichia coli populations and prevalence of enterohaemorrhagic E. coli virulence genes in cattle faecesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2005R.A. Gilbert Abstract Aim:, To determine the effect of different carbohydrate-based finishing diets on fermentation characteristics and the shedding of Escherichia coli and enterohaemorrhagic E. coli (EHEC) virulence genes in cattle faeces. Methods and Results:, The size of faecal E. coli populations and fermentation characteristics were ascertained in three experiments where cattle were maintained on a range of finishing diets including high grain, roughage, and roughage + molasses (50%) diets. Increased E. coli numbers, decreased pH and enhanced butyrate and lactate fermentation pathways were associated with grain diets, whereas roughage and roughage + molasses diets resulted in decreased concentrations of ehxA, eaeA and stx1 genes, this trend remaining at lairage. In one experiment, faecal E. coli numbers were significantly lower in animals fed roughage and roughage + molasses, than animals fed grain (4·5, 5·2 and 6·3 mean log10 g,1 digesta respectively). In a second experiment, faecal E. coli numbers were 2 log lower in the roughage and roughage + molasses diets compared with grain-fed animals prior to lairage (5·6, 5·5 and 7·9 mean log10 g,1 digesta respectively) this difference increasing to 2·5 log at lairage. Conclusions:, The type of dietary carbohydrate has a significant effect on E. coli numbers and concentration of EHEC virulence genes in faeces of cattle. Significance and Impact of the Study:, The study provides a better understanding of the impact finishing diet and commercial lairage management practices may have on the shedding of E. coli and EHEC virulence factors, thus reducing the risk of carcass contamination by EHEC. [source] Quantification and prevalence of Salmonella in beef cattle presenting at slaughterJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2004N. Fegan Abstract Aims:, A survey to determine the prevalence and numbers of Salmonella in beef cattle presented for slaughter at abattoirs across Australia was conducted between September 2002 and January 2003. Methods and Results:, Automated immunomagnetic separation (AIMS) was used for detection and isolation of Salmonella enriched from cattle faeces. Salmonella were enumerated from positive samples using a combination of the Most Probable Number (MPN) technique and AIMS. A total of 310 faecal samples were tested, 155 were from lot-fed cattle and 155 from grass-fed cattle. Salmonella spp. were isolated from 21 (6·8%) of the cattle and the prevalence amongst grass-fed cattle (4·5%) was not significantly different to that found in lot-fed cattle (9%). Counts of Salmonella in positive faeces varied from <3 MPN g,1 of faeces to 2·8 × 103 MPN g,1 and 71% of positive samples had counts <10 MPN g,1 faeces. There was no significant difference in the mean log10 number of Salmonella in faeces of cattle from each production system. Conclusion:, Low numbers of beef cattle were found to shed Salmonella at the time of slaughter and the prevalence and the associated faecal concentrations did not vary significantly with the pre-slaughter production system (grass or lot feeding). The faecal concentration of Salmonella in the majority of faeces was low (<10 MPN g,1) with few high concentrations up to 3 × 103 MPN g,1, suggesting there may be a low risk of carcase contamination. Significance and Impact of the Study:, Beef cattle do not appear to be a major source of entry of Salmonella into the human food chain and the quantitative information contained in this study can be used in quantitative assessments of the associated risk of human salmonellosis. [source] A comparison of two pre-enrichment media prior to immunomagnetic separation for the isolation of E. coli O157 from bovine faecesJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2003G. Foster Abstract Aims: To compare the sensitivity of two pre-enrichment broth media prior to immunomagnetic separation for the isolation of Escherichia coli O157 from cattle faeces. Methods and Results: One-gram portions of 721 cattle faeces collected from 43 farms were pre-enriched in buffered peptone water containing vancomycin, cefixime and cefsulodin (BPW-VCC) and buffered peptone water without additives (BPW-WOA), respectively. A total of 137 samples were positive for E. coli O157: 127 pre-enriched with BPW-WOA and 89 pre-enriched in BPW-VCC. Representative isolates were tested for phage type, verotoxin and eae (E. coli attaching and effacing) gene sequences, resulting in the recognition of eight different types. All the E. coli O157 types recognized were isolated by both methods except for three different strains, each of which were isolated only on a single occasion: two by BPW-WOA and another by BPW-VCC. Conclusions: The results clearly demonstrate, under the conditions of this study, that BPW without antibiotics was the superior pre-enrichment medium for the isolation of E. coli O157 from cattle faeces. Significance and Impact of the Study: The use of BPW-WOA in preference to BPW-VCC for the isolation of E. coli O157 from cattle faeces in future research and outbreak studies should lead to a higher number of positive isolates. [source] Enumeration of Escherichia coli O157 in cattle faeces using most probable number technique and automated immunomagnetic separationLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2004N. Fegan Abstract Aims:, To determine the numbers of Escherichia coli O157 present in the faeces of naturally infected cattle. Methods and Results:, A combination of the most probable number (MPN) technique and automated immunomagnetic separation (AIMS) was used to enumerate E. coli O157 in cattle faeces from both pasture-fed and grain-fed animals. A total of 22 E. coli O157 positive faecal samples were enumerated for E. coli O157 (10 from pasture-fed and 12 from grain-fed animals). The numbers of E. coli O157 in cattle faeces varied from undetectable (<3 MPN g,1 of faeces) to 2·4 × 104 MPN g,1. There was no significant difference (P = 0·06) between the numbers of E. coli O157 in pasture-fed or grain-fed cattle faeces, although the geometric mean (antilog of the mean of log10 transformed MPN values) was higher in grain-fed (130 MPN g,1) than in pasture-fed (13 MPN g,1). Conclusions:, Although the number of samples tested is small, the results indicate that E. coli O157 make up a small proportion of the total E. coli population present in cattle faeces. Significance and Impact of the Study:, Information on the numbers of E. coli O157 present in cattle will assist in developing more robust quantitative risk assessments and formulating intervention strategies. [source] | ||||||||||