The authors would like to acknowledge Latoya Wiggins and Katelyn Griffin for their assistance in sample acquisition, as well as Laura Lee Rutherford for their assistance in sampling and molecular analyses. We would also like to thank Sarah Owens from Argonne National Lab for microbiomic sample preparation and sequencing. These investigations were supported equally by the Agricultural Research Service, USDA CRIS Projects &#8220;Pathogen Reduction and Processing Parameters in Poultry Processing Systems&#8221; #6612-41420-017-00 and &#8220;Molecular Approaches for the Characterization of Foodborne Pathogens in Poultry&#8221; #6612-32000-059-00.

1. Mechanical Homogenization of Environmental Poultry Production Samples
<ol style="margin-left: 40px;">
	<li>Prior to extraction, set a water bath to 95 &#176;C and allow the water bath time to reach that temperature.</li>
	<li>Weigh out 0.33 g of soil or fecal material into a 2 ml Lysing Matrix E tube.
	<ol>
		<li>Do not exceed 0.33 g of sample in the tube, since this will cause the following solutions to exceed the capacity of the tube.</li>
		<li>Thaw frozen samples to RT prior to weighing.</li>
		<li>In order to analyze a total of 1 g of soil/feces, weigh out 3 replicate 0.33 g samples for each individual environmental sample.</li>
		<li>Store samples at -20 &#176;C within the conical matrix tubes prior to extraction, if needed.</li>
	</ol>
	</li>
	<li>Add 825 &#181;l Sodium Phosphate Buffer and 275 &#181;l of PLS solution to a sample tube. Mix using a vortex for ~15 sec and then centrifuge the samples at 14,000 x g for 5 min.</li>
	<li>Decant the supernatant and add 700 &#181;l of Buffer ASL. Mix using a vortex for 5 sec.
	<ol>
		<li>Ensure that there is headspace (~10% total volume) available in the conical tube at this point. If there is no headspace, the tubes will have a tendency to leak during the next homogenization step which could lead to cross-contamination and/or sample loss.</li>
	</ol>
	</li>
	<li>Place the samples into a FastPrep 24 Instrument, and homogenize the samples at a speed of 6.0 m/sec for 40 sec.</li>
	<li>Centrifuge the homogenized sample at 14,000 x g for 5 min. Transfer the supernatant to a sterile 2 ml microcentrifuge tube.</li>
	<li>To maximize the DNA recovery from the sample, repeat steps 1.4 to 1.6, combining the supernatants into the same sterile, 2 ml microcentrifuge tube.</li>
</ol>
2. Enzymatic Inhibition of Inhibitors from Sample Homogenates
NOTE: This protocol uses the QIAamp DNA Stool Mini Kit.
<ol style="margin-left: 40px;">
	<li>Incubate the supernatant in a 95 &#176;C water bath for 5 min to maximize DNA recovery from any remaining cells within the supernatant.
	<ol>
		<li>Incubate at 70 &#176;C for samples containing mostly Gram-negative organisms. However if Gram-positive organisms are present (which is the case with poultry fecal samples), incubate at 95 &#176;C.</li>
		<li>Use plastic locking clips on the microcentrifuge tubes to ensure that the tubes will not &#8220;pop&#8221; open and potentially lose sample volume as pressure can build up in these sealed microcentrifuge tubes.</li>
	</ol>
	</li>
	<li>Open each microcentrifuge tube to release the pressure, re-cap the microcentrifuge tubes and mix using a vortex for 15 sec.</li>
	<li>Centrifuge the sample at 14,000 x g for 1 min, remove 1.2 ml of the supernatant and place it into a new sterile 2 ml microcentrifuge tube.</li>
	<li>Add 1 InhibitEx tab to each sample, and mix using a vortex until the sample becomes a uniformly white/off-white liquid.
	<ol>
		<li>Avoid touching the InhibitEx tab while placing it into the microcentrifuge tube containing the sample. To accomplish this, place the blister pack containing the tab directly over the open microcentrifuge tube and gently push the tab out of the blister pack and into the microcentrifuge tube.</li>
	</ol>
	</li>
	<li>Incubate the sample for 1 min at RT (~ 25 &#176;C) and centrifuge at 14,000 x g for 5 min.</li>
	<li>Transfer all liquid to a sterile 1.5 ml microcentrifuge tube and centrifuge at 14,000 x g for 5 min.
	<ol>
		<li>Avoid any remaining particulates that may have pelleted at the bottom of the microcentrifuge tube at the end of step 2.5 when transferring the liquid.</li>
	</ol>
	</li>
</ol>
3. Automated DNA Purification Using the QIAcube Robotic Workstation
NOTE: The number of plastic consumables, the arrangement of the sample rotor adapters within the centrifuge, and the required volumes of the buffers/solutions are dependent on the number of samples that are being run.
<ol style="margin-left: 40px;">
	<li>Add elution tubes and filter tubes to the appropriate slots within the rotor adapters. For each sample, add 400 &#181;l to the middle slot of the rotor adapter. Place the rotor adapters in the workstation centrifuge in the correct arrangement according to the number of samples being purified.
	<ol>
		<li>Make sure that all of the microcentrifuge tube lids are properly secured within the rotor adapter since a failure to do so could result in shearing during one of the centrifugation steps of the purification protocol.</li>
	</ol>
	</li>
	<li>Add the required number of 1,000 &#181;l and 200 &#181;l filter-tips to the workstation, and fill the supplied buffer bottles with the required volume of buffers. 
	NOTE: The buffers required for this purification protocol (AL, AW1, AW2, and AE) are all contained within the QIAamp DNA Stool Mini Kit. The user needs to supply the 100% ethanol that is needed for the AW buffers and as a solution used in the purification process.</li>
	<li>Add the required volume of the supplied proteinase K solution into a sterile 1.5 ml microcentrifuge tube and place it into slot A on the workstation. Also, add the required number (equal to the number of samples being purified) of 2 ml safe-lock microcentrifuge sample tubes RB to the shaker section of the workstation.
	<ol>
		<li>Ensure that the lids of the sample tubes are securely placed into the appropriate slots on the workstation, since a failure to do so will result in an error when the machine initially scans the workstation to make sure all needed plastics and liquids are available for the requested run.</li>
	</ol>
	</li>
	<li>Using the touchscreen on the workstation, select the DNA Stool &#8211; Human Stool &#8211; Pathogen Detection Protocol, and read through the subsequent screens to ensure that the workstation was loaded correctly. Once all check screens are passed, select Start to run this protocol.
	<ol>
		<li>If extracting DNA from more than 12 samples, begin the homogenization process (Step 1) for the next set of samples, since a run of 12 samples takes ~72 min to complete on the workstation.</li>
	</ol>
	</li>
	<li>Remove the samples from the rotor adapters, cap them, and place at -20 &#176;C until needed for subsequent downstream analyses.
	<ol>
		<li>At this point, combine the 3 replicate purifications for an individual sample (total analyzed amount = 1 g) using a centrifugation/evaporation-based system. Combine the replicates and re-elute to a final volume of 100 &#181;l of Tris-ETDA buffer.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Maukonen, J., Simoes, C., Saarela, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+currently+used+commercial+DNA-extraction+methods+give+different+results+of+clostridial+and+actinobacterial+populations+derived+from+human+fecal+samples.">The currently used commercial DNA-extraction methods give different results of clostridial and actinobacterial populations derived from human fecal samples.</a> FEMS microbiology ecology. 79, 697-708 (2012).</li><li>Tang, J. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+effective+method+for+isolation+of+DNA+from+pig+faeces+and+comparison+of+five+different+methods.">An effective method for isolation of DNA from pig faeces and comparison of five different methods.</a> Journal of microbiological. 75, 432-436 (2008).</li><li>McOrist, A. L., Jackson, M., Bird, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+five+methods+for+extraction+of+bacterial+DNA+from+human+faecal+samples.">A comparison of five methods for extraction of bacterial DNA from human faecal samples.</a> Journal of microbiological. 50, 131-139 (2002).</li><li>Ariefdjohan, M. W., Savaiano, D. A., Nakatsu, C. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+DNA+extraction+kits+for+PCR-DGGE+analysis+of+human+intestinal+microbial+communities+from+fecal+specimens.">Comparison of DNA extraction kits for PCR-DGGE analysis of human intestinal microbial communities from fecal specimens.</a> Nutrition journal. 9, 23 (2010).</li><li>Carrigg, C., Rice, O., Kavanagh, S., Collins, G., O'Flaherty, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+extraction+method+affects+microbial+community+profiles+from+soils+and+sediment.">DNA extraction method affects microbial community profiles from soils and sediment.</a> Applied microbiology and biotechnology. 77, 955-964 (2007).</li><li>Smith, B., Li, N., Andersen, A. S., Slotved, H. C., Krogfelt, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimising+Bacterial+DNA+Extraction+from+Faecal+Samples:+Comparison+of+Three+Methods.">Optimising Bacterial DNA Extraction from Faecal Samples: Comparison of Three Methods.</a> The Open microbiology journal. 5, 14-17 (2011).</li><li>Claassen, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+the+efficiency+of+five+different+commercial+DNA+extraction+kits+for+extraction+of+DNA+from+faecal+samples.">A comparison of the efficiency of five different commercial DNA extraction kits for extraction of DNA from faecal samples.</a> Journal of microbiological. 94, 103-110 (2013).</li><li>Scupham, A. J., Jones, J. A., Wesley, I. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+DNA+extraction+methods+for+analysis+of+turkey+cecal+microbiota.">Comparison of DNA extraction methods for analysis of turkey cecal microbiota.</a> Journal of applied microbiology. 102, 401-409 (2007).</li><li>Salonen, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+analysis+of+fecal+DNA+extraction+methods+with+phylogenetic+microarray:+effective+recovery+of+bacterial+and+archaeal+DNA+using+mechanical+cell+lysis.">Comparative analysis of fecal DNA extraction methods with phylogenetic microarray: effective recovery of bacterial and archaeal DNA using mechanical cell lysis.</a> Journal of microbiological methods. 81, 127-134 (2010).</li><li>Peng, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+direct+boiling+method+with+commercial+kits+for+extracting+fecal+microbiome+DNA+by+Illumina+sequencing+of+16S+rRNA+tags.">Comparison of direct boiling method with commercial kits for extracting fecal microbiome DNA by Illumina sequencing of 16S rRNA tags.</a> Journal of microbiological. 95, 455-462 (2013).</li><li>Yuan, S., Cohen, D. B., Ravel, J., Abdo, Z., Forney, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+methods+for+the+extraction+and+purification+of+DNA+from+the+human+microbiome.">Evaluation of methods for the extraction and purification of DNA from the human microbiome.</a> PloS one. 7, 33865 (2012).</li><li>Qu, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+Metagenomics+Reveals+Host+Specific+Metavirulomes+and+Horizontal+Gene+Transfer+Elements+in+the+Chicken+Cecum+Microbiome.">Comparative Metagenomics Reveals Host Specific Metavirulomes and Horizontal Gene Transfer Elements in the Chicken Cecum Microbiome.</a> PloS one. 3, 2945 (2008).</li><li>Sekelja, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Abrupt+temporal+fluctuations+in+the+chicken+fecal+microbiota+are+explained+by+its+gastrointestinal+origin.">Abrupt temporal fluctuations in the chicken fecal microbiota are explained by its gastrointestinal origin.</a> Applied and environmental microbiology. 78, 2941-2948 (2012).</li><li>Oakley, B. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Poultry-Associated+Microbiome:+Network+Analysis+and+Farm-to-Fork+Characterizations.">The Poultry-Associated Microbiome: Network Analysis and Farm-to-Fork Characterizations.</a> PloS one. 8, 57190 (2013).</li><li>Cook, K. L., Rothrock, M. J., Eiteman, M. A., Lovanh, N., Sistani, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+nitrogen+retention+and+microbial+populations+in+poultry+litter+treated+with+chemical,+biological+or+adsorbent+amendments.">Evaluation of nitrogen retention and microbial populations in poultry litter treated with chemical, biological or adsorbent amendments.</a> Journal of environmental management. 92, 1760-1766 (2011).</li><li>Rothrock, M. J., Cook, K. L., Warren, J. G., Eiteman, M. A., Sistani, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+mineralization+of+organic+nitrogen+forms+in+poultry+litters.">Microbial mineralization of organic nitrogen forms in poultry litters.</a> Journal of environmental quality. 39, 1848-1857 (2010).</li><li>Rothrock, M. J., Cook, K. L., Warren, J. G., Sistani, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+alum+addition+on+microbial+communities+in+poultry+litter.">The effect of alum addition on microbial communities in poultry litter.</a> Poultry science. 87, 1493-1503 (2008).</li><li>Li, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+QIAamp+DNA+Stool+Mini+Kit+for+ecological+studies+of+gut+microbiota.">Evaluation of QIAamp DNA Stool Mini Kit for ecological studies of gut microbiota.</a> Journal of microbiological. 54, 13-20 (2003).</li><li>Dridi, B., Henry, M., El Khechine, A., Raoult, D., Drancourt, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+precalence+of+Methanobrevibacter+smithii+and+Methanosphaera+stadtmanae+detected+in+the+human+gut+using+an+improved+DNA+detection+protocol.">High precalence of Methanobrevibacter smithii and Methanosphaera stadtmanae detected in the human gut using an improved DNA detection protocol.</a> PloS one. 4, 7063 (2009).</li><li>Harms, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-time+PCR+quantification+of+nitrifying+bacteria+in+a+municipal+wastewater+treatment+plant.">Real-time PCR quantification of nitrifying bacteria in a municipal wastewater treatment plant.</a> Environmental science and technology. 37, 343-351 (2003).</li><li>Rothrock, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+microvolume+DNA+quantification+methods+for+use+with+volume-sensitive+environmental+DNA+extracts.">Comparison of microvolume DNA quantification methods for use with volume-sensitive environmental DNA extracts.</a> Journal of natural and environmental sciences. 2, 34-38 (2011).</li><li>Navas-Molina, J. A., DeLong Edward, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Methods in Enzymology. 531, 371-444 (2013).</li><li>Caporaso, J. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultra-high-throughput+microbial+community+analysis+on+the+Illumina+HiSeq+and+MiSeq+platforms.">Ultra-high-throughput microbial community analysis on the Illumina HiSeq and MiSeq platforms.</a> The ISME journal. 6, 1621-1624 (2012).</li><li>Caporaso, J. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+patterns+of+16S+rRNA+diversity+at+a+depth+of+millions+of+sequences+per+sample.">Global patterns of 16S rRNA diversity at a depth of millions of sequences per sample.</a> Proceedings of the National Academy of Sciences of the United States of America. 108 Suppl 1, 4516-4522 (2011).</li><li>Caporaso, J. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=QIIME+allows+analysis+of+high-throughput+community+sequencing+data.">QIIME allows analysis of high-throughput community sequencing data.</a> Nature methods. 7, 335-336 (2010).</li><li>Edgar, R. C., Haas, B. J., Clemente, J. C., Quince, C., Knight, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=UCHIME+improves+sensitivity+and+speed+of+chimera+detection.">UCHIME improves sensitivity and speed of chimera detection.</a> Bioinformatics. 27, 2194-2200 (2011).</li><li>Edgar, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Search+and+clustering+orders+of+magnitude+faster+than+BLAST.">Search and clustering orders of magnitude faster than BLAST.</a> Bioinformatics. 26, 2460-2461 (2010).</li><li>DeSantis, T. Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Greengenes,+a+chimera-checked+16S+rRNA+gene+database+and+workbench+compatible+with+ARB.">Greengenes, a chimera-checked 16S rRNA gene database and workbench compatible with ARB.</a> Applied and environmental microbiology. 72, 5069-5072 (2006).</li><li>Caporaso, J. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PyNAST:+a+flexible+tool+for+aligning+sequences+to+a+template+alignment.">PyNAST: a flexible tool for aligning sequences to a template alignment.</a> Bioinformatics. 26, 266-267 (2010).</li><li>Price, M. N., Dehal, P. S., Arkin, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FastTree+2&#8211;approximately+maximum-likelihood+trees+for+large+alignments.">FastTree 2&#8211;approximately maximum-likelihood trees for large alignments.</a> PloS one. 5, 9490 (2010).</li><li>Cook, K. L., Rothrock, M. J., Lovanh, N., Sorrell, J. K., Loughrin, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+temporal+changes+in+the+microbial+community+in+an+anaerobic+swine+waste+treatment+lagoon.">Spatial and temporal changes in the microbial community in an anaerobic swine waste treatment lagoon.</a> Anaerobe. 16, 74-82 (2010).</li><li>Cook, K. L., Rothrock, M. J., Warren, J. G., Sistani, K. R., Moore, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+alum+treatment+on+the+concentration+of+total+and+ureolytic+microorganisms+in+poultry+litter.">Effect of alum treatment on the concentration of total and ureolytic microorganisms in poultry litter.</a> Journal of environmental quality. 37, 2360-2367 (2008).</li><li>Lovanh, N., Cook, K. L., Rothrock, M. J., Miles, D. M., Sistani, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+shifts+in+microbial+population+structure+within+poultry+litter+associated+with+physicochemical+properties.">Spatial shifts in microbial population structure within poultry litter associated with physicochemical properties.</a> Poultry science. 86, 1840-1849 (2007).</li></ol>

The authors have nothing to disclose.

The DNA extraction method used effected the quantitative and qualitative total bacterial community estimates for both the fecal and litter samples, supporting the sample analyses dependent nature of DNA extraction methods seen previously1,3,6. For both the fecal and litter samples, the order of performance of the DNA extraction methods was different for the quantitative (Mechanical &#62; Hybrid &#62; Enzymatic) and the qualitative (Enzymatic &#62; Hybrid &#62; Mechanical) total bacterial community estimates. W...

When analyzing complex clinical or environmental samples (e.g., feces, soils), there are two main methodologies used for the extraction of DNA. The first is a mechanical disruption of the matrix using an intense bead-beating step, while the second is an enzymatic disruption of the matrix to chemically release bacterial cells and inhibit PCR inhibitors from the matrix simultaneously. Given the different means by which these two types of extraction methods work, it is not surprising that previous studies demonstrated that the appropriate DNA extraction method is both highly sample and analysis dependent. Comparative DNA extraction studies previously showed that some methods are more appropriate for improved DNA quality and quantity from environmental samples1-3, while others demonstrated improvements for community-level analyses such as denaturing gradient gel electrophoresis (DGGE)4-6, terminal restriction fragment length polymorphism (T-RFLP)7, automated ribosomal intergenic spacer analysis (ARISA)8, and phylogenetic microarrays9. Therefore, appropriate DNA extraction methods need to be used, or developed, according to the types of environmental samples and the types of analyses being performed on those samples, especially given the recent advancements in bacterial community analyses. 
Next generation sequencing, in conjunction with more quantitative community assessments (e.g., quantitative PCR (qPCR)), is becoming more prevalent in the environmental and clinical sciences, however, very little research has been performed to determine the effect of DNA extraction methods on these data sets. Most DNA extraction comparison studies dealt with microbiomic community estimates from human or human model samples10,11, not agricultural animal samples. The few poultry-focused next generation sequencing studies dealt with specific metagenomic12,13 or microbiomic14 questions; they did not discuss the effect of DNA extraction method on the resulting microbiomic analyses. Considering the complex nature of environmental samples related to poultry production (e.g., feces, litter/bedding, pasture soil), DNA extraction methods need to be carefully selected. Poultry-related environmental samples are known to contain large numbers of PCR inhibitors and up to 500-fold DNA extract dilutions have been required for PCR and subsequent downstream analysis15-17. Therefore it is essential that DNA extraction methods be optimized for these types of samples in order to not only physically disrupt the matrix, but also to be able to reduce/eliminate the large number of inhibitors that are present. 
The QIAamp DNA Stool Mini Kit, an enzymatic extraction method, has been considered the &#8220;gold standard&#8221; when extracting DNA from difficult gut/fecal samples1,18,19 and has been applied successfully to poultry environmental samples8,14. The enzymatic removal of PCR inhibitors through the use of a proprietary matrix is one of the greatest advantages of using this method for these types of environmental samples, as is the ability to significantly improve throughput (and reduce sample processing error) using automated workstations. One major disadvantage is the lack of a mechanical homogenization step to physically disassociate bacterial cells from the environmental matrix. When testing gut and fecal samples of non-poultry origin, the addition of a bead-beating or mechanical disruption step within a DNA extraction protocol significantly increased extraction efficiency9, DNA yield/quality1,4,5 and significantly improved downstream community analyses in terms of richness, diversity, and coverage5,6,11. These studies compared not only mechanical bead-beating methods to the &#8220;gold standard&#8221; enzymatic method, but some also added the mechanical bead-beating step to the enzymatic protocol to improve results6,9,11. 
According to the results from the above studies, bacterial community analyses (both qualitative and quantitative) could be improved from poultry-related environmental samples through the addition of a mechanical homogenization step to the enzymatic method. Therefore, the goal of this study was twofold: (1) to develop a novel DNA extraction technique that utilizes the most desirable aspects of both the mechanical (powerful homogenization step) and enzymatic (PCR inhibitor removal and automation) extraction methods and (2) compare the quantitative (via qPCR) and qualitative (via microbiomics) bacterial community assessments of this novel method to representative mechanical and enzymatic methods.

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:71px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Lysing Matrix E tube</td>
			<td style="width:71px;">MPBio</td>
			<td style="width:119px;">6914-050</td>
			<td>Different sizes available and the last 3 numbers of the cat. No. indicate size (-050 = 50 tubes, -200 = 200 tubes, -1000 = 1000 tubes)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sodium Phosphate Solution</td>
			<td style="width:71px;">MPBio</td>
			<td style="width:119px;">6570-205</td>
			<td>Can be purchased individually, or also contained within the FastDNA Spin Kit for Feces (Cat. No. 116570200)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">PLS Buffer</td>
			<td style="width:71px;">MPBio</td>
			<td style="width:119px;">6570-201</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Buffer ASL (560 ml)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">19082</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">FastPrep 24 homogenizer</td>
			<td style="width:71px;">MPBio</td>
			<td align="right" style="width:119px;">116004500</td>
			<td>48 x 2 ml HiPrep adapter (Cat. No. 116002527) available to double throughput of mechanical homogenization step</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">QIAamp DNA Stool Mini Kit</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">51504</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">QIAcube24 (110V)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">9001292</td>
			<td>Preliminary results show that QIAcube HT (Cat. No. 9001793) can be used to improve throughput, but different consumables are required of this machine and more comparative work needs to be done.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Filter-Tips, 1000 ml (1024)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">990352</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Filter-Tips, 200 ml (1024)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">990332</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">QIAcube Rotor Adapters (10 x 24)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">990394</td>
			<td>For 1.5 ml microcentrifuge tubes included with in the rotor adapter kit there is an alternative.&#160; It is Sarstedt Micro tube 1.5 ml Safety Cap, Cat. No. 72.690</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sample Tubes RB (2 ml)</td>
			<td style="width:71px;">Qiagen</td>
			<td align="right" style="width:119px;">990381</td>
			<td>Alternative: Eppendorf Safe-Lok micro test tube, Cat. No. 022363352</td>
		</tr>
	</tbody>
</table>

a hybrid dna extraction method for the qualitative and quantitative assessment of bacterial communities from poultry production samples

A eficácia dos protocolos de extracção de ADN podem ser altamente dependente tanto do tipo de amostra a ser investigada e os tipos de análises realizadas a jusante. Considerando-se que a utilização de novas técnicas de análise da comunidade bacteriana (por exemplo, microbiomics, metagenómica) está se tornando mais prevalente nas ciências agrícolas e ambientais e muitas amostras ambientais dentro dessas disciplinas pode ser physiochemically e microbiologicamente único (por exemplo, fezes e amostras de maca / cama de o espectro de produção de aves), métodos de extração de DNA apropriadas e efetivas precisam ser cuidadosamente escolhido. Portanto, um novo método semi-automatizado de extração de DNA híbrido foi desenvolvido especificamente para uso com amostras de produção de aves ambiental. Este método é uma combinação dos dois tipos principais de extracção de ADN: mecânica e enzimática. A intensa etapa de homogeneização mecânica de duas etapas (usando talão batendo formulado especificamente para ambientesAmostras Tal) foi adicionado ao início do método &quot;padrão de ouro&quot; de extracção de ADN enzimático para as amostras fecais para melhorar a remoção de bactérias e ADN a partir da matriz da amostra e melhorar a recuperação dos membros Gram-positivas comunitárias bacterianas. Uma vez que a porção de extração enzimática do método híbrido foi iniciada, o restante processo de purificação foi automatizado usando uma estação de trabalho robótica para aumentar a produtividade de amostras e diminuir o erro de processamento da amostra. Em comparação com os rigorosos métodos de extração de DNA mecânicos e enzimáticos, este método híbrido novela proporcionou o melhor desempenho global combinada ao considerar quantitativa (usando 16rRNA qPCR) e qualitativa (usando microbiomics) estimativas do total de comunidades bacterianas ao processar fezes de aves e amostras de serapilheira .

For this study, fresh fecal droppings and litter samples were recovered from a commercial broiler house (~25,000 birds) in the southeastern US. The broilers (Gallus gallus) were Cobb-500 crosses, and they were 59 days old at the time of sampling. Fresh fecal and litter samples were recovered from four distinct areas within the house (near cooling pad, near the waterer/feeder lines, in between the waterer/feeder lines, and near exhaust fans), and samples from each of these areas contained five pooled samples from...

Watch this Scientific Journal Video about A Hybrid DNA Extraction Method for the Qualitative and Quantitative Assessment of Bacterial Communities from Poultry Production Samples at JoVE.com

A Hybrid DNA Extraction Method for the Qualitative and Quantitative Assessment of Bacterial Communities from Poultry Production Samples

A novel semi-automated hybrid DNA extraction method for use with environmental poultry production samples was developed and demonstrated improvements over a common mechanical and enzymatic extraction method in terms of the quantitative and qualitative estimates of the total bacterial communities.

Um método de extração de DNA híbrido para a Avaliação de comunidades bacterianas Qualitativa e Quantitativa de amostras de produção de aves de capoeira

The efficacy of DNA extraction protocols can be highly dependent upon both the type of sample being investigated and the types of downstream analyses ...

a-hybrid-dna-extraction-method-for-qualitative-quantitative

Research

JoVE Journal

Biology

14.4K visualizações.  USDA-Agricultural Research Service. A novel semi-automated hybrid DNA extraction method for use with environmental poultry production samples was developed and demonstrated improvements over a common mechanical and enzymatic extraction method in terms of the quantitative and qualitative estimates of the total bacterial communities. 