This work was supported by the National Key Research and Development Project (2019YFA0904003); Modern Agricultural Industrial System in Shandong Province (SDAIT-011-09); International Cooperation Platform Optimization Project (CXGC2023G15); Major Innovation tasks of agricultural Science and technology innovation project of Academy of Agricultural Sciences Shandong, China (CXGC2023G03).

The Salmonella strains used in this study were collected from poultry in Shandong, China, after obtaining approval from the Biosafety Committee of the Institute of Animal Sciences and Veterinary Medicine, Shandong Academy of Agricultural Sciences, China.
1. Application of the intelligent high-throughput AST system8
<ol>
	<li>Inoculum preparation
	<ol>
		<li>Incubate the quality control organism Escherichia coli and 93 Salmonella strains to be tested for AST on Mueller-Hinton agar (MHA) plates for 16-18 h at 37 &#176;C3.</li>
		<li>Prepare the inoculum of each strain to match 0.5 McFarland turbidity standard based on the method specified in the CLSI standard3and then dilute 10 times.</li>
		<li>Place 200 &#181;L of sterile normal saline into the horizontal 1st well (A1) of the 96-well plate as the negative control, two suspensions of quality control organism into the horizontal 2nd and 3rd wells (A2 and A3) as the positive control, and quality control, respectively. Add 200 &#181;L of the diluted inoculum suspensions of each tested stain into the corresponding 93 wells in the 96-well seed block.</li>
	</ol>
	</li>
	<li>Preparation of antimicrobial agar plate
	<ol>
		<li>Set the concentration ranges of different antibacterial agents tested according to the calculation range of the Lar index (from 0.125R to 8R). The concentrations range from the quality control range or 0.0625R (subject to the lower range) to 8R. 
		NOTE: If the Lar index is not calculated, the range of antibiotic concentrations can be set according to the needs of AST.</li>
		<li>Execute a log2 doubling dilution scheme for antibiotic solution beginning with a suitable stock concentration based on the agar dilution method specified in the CLSI standard3.</li>
		<li>Sterilize 50 mL glass bottles containing 18 mL of Mueller-Hinton agar media. Add 2 mL of the appropriate dilutions of the antimicrobial solution to 18 mL of molten media cooled to 45-50 &#176;C, mix thoroughly, and pour into the plates in the biosafety cabinet.</li>
		<li>Allow the agar to solidify at room temperature (RT), leave a gap under the lid of incubated plates and blow to dry the agar surface before inoculating.</li>
		<li>Label the types of antimicrobial agents and concentrations on the reverse side of the incubated plates. Arrange the multiple incubated plates of each antimicrobial agent in a stack in log2-doubling dilution order.</li>
		<li>Prepare two drug-free agar plates as the controls for each antimicrobial agent.</li>
	</ol>
	</li>
	<li>Inoculation steps for 96-dot matrix inoculator
	<ol>
		<li>Install the autoclaved inoculation pin plate on the support of a 96-dot matrix inoculator in the biosafety cabinet.</li>
		<li>Place the prepared seed block with tested strains and an agar incubated plate on the mobile carrier, with the same positioning angle for the two plates.</li>
		<li>Push the mobile carrier so the seed block is directly below the inoculation pin plate.</li>
		<li>Press the operating handle, move the inoculation pin plate down, and direct the 96 pins to the inocula in 96 wells of the seed block.</li>
		<li>Release the operating handle with control, then reset the inoculation pin plate under the action of the spring.</li>
		<li>Press the operating handle 2-3 times to stir each inoculum well and dip. Push and move the carrier plate so the incubated plate is directly below the inoculation pin plate.</li>
		<li>Press the operating handle, move the inoculation pin plate down, and stop for 1-2 s to make the inoculation pins contact the surface of the incubated plate fully.</li>
		<li>Release the operating handle. This completes one inoculation. Replace another incubated plate and continue the cycle until one group of antimicrobial agar plates is finished.</li>
		<li>Replace another inoculation pin plate and seed block, and inoculate another group of tested strains. Cycle until all inoculations are completed. 
		NOTE: Inoculate a control agar plate (no antimicrobial agent) first, then the plate in order of drug concentration from low to high, and a second control agar plate last to ensure no contamination or antimicrobial agent carry-over. The inoculating volume relies on the volume of the natural deposition of each pin of approximately 2 &#181;L.</li>
	</ol>
	</li>
	<li>Incubating the antimicrobial agar plates
	<ol>
		<li>Incubate the inoculated antimicrobial agar plates at RT until the moisture in the inoculum spots is absorbed into the agar.</li>
		<li>Invert the plates and incubate them for 16-20 h at 37 &#176;C for the tested strains to ensure that the uninhibited bacteria form colonies.</li>
	</ol>
	</li>
	<li>Image acquisition and data statistics
	<ol>
		<li>Double-click on 96-dot matrix AST image acquisition system to open the program.</li>
		<li>Click on Test Information in the taskbar. Click on New to create a new test task, and fill in the information according to the prompts, including the code, name, source, bacteria, number of strains, antibiotics, and gradient.</li>
		<li>Click on Data Collection &#62; Photograph &#62; Test item to select the new task created. Click on Antibiotics to select the name of the antibiotic, and click on Gradient to select the initial concentration of this antibiotic.</li>
		<li>Click on Connect to connect with the image acquisition converter.</li>
		<li>Place the corresponding incubated plates on the detection plate base with the missing angle at the right front for orientation and push into the image acquisition converter.</li>
		<li>Click on Collection to obtain the images. The antibiotic gradient will automatically jump to the next gradient. Place the next plate in turn and continue to click on Collection until the plates for this antibiotic have been collected.</li>
		<li>Click on Antibiotics, and select the next set of incubated plates. Click on Gradient to select the starting gradient and proceed to the next round of image collection.</li>
		<li>After completing all collections, click on Submit. The program will automatically recognize the number of white pixels formatted at each inoculation point in the images, determine if there is colony formation and convert the images into MIC values.</li>
		<li>Click on Query to obtain all MIC results of the strains against the tested antibiotics. 
		NOTE: The intelligent high throughput AST system is suitable for determining MICs of large batches of bacterial strains. The testing process, including preparation, inoculation, incubation, and result reading, takes 3 days. The types of antibiotics and MIC detection ranges can be set according to respective needs, and the main consumables can be reused.</li>
	</ol>
	</li>
	<li>Calculation of the Lar index
	<ol>
		<li>Determine the Lar index accurately with the formula: <img alt="Equation 1" src="/files/ftp_upload/64785/64785eq01.jpg" style="margin: auto;" />, where: 
		MICi: minimum inhibitory concentration. 
		The range of MIC distributions from MIC-3 to MIC3 represents serial twofold concentrations centered on R: 0.125R, 0.25R, 0.5R, R, 2R, 4R, and 8R. 
		<img alt="Equation 2" src="/files/ftp_upload/64785/64785eq02.jpg" style="margin: auto;" /> is 2i, and the range of i is -3 to 3. 
		R: the breakpoints of resistance of bacteria against antimicrobial agents standardized by CLSI. 
		f: the MIC frequency distribution. 
		NOTE: The general Lar index is the arithmetic mean of all Lar indices. After the Lar index is calculated, round off the final value to two significant digits after the decimal point.</li>
	</ol>
	</li>
</ol>
2. Intelligent high-throughput phage screening system9
<ol>
	<li>Preparing the phage seed block and double-layer incubated plates containing bacteria.
	<ol>
		<li>Use the double-layer agar method10 or liquid culture method11 for making different phages. Dilute to a suitable parallel concentration with a titer of 1 x 104-5 pfu/mL, and add 200 &#181;L of the phage inoculum into the 96-well seed block.</li>
		<li>Make double-layered plates with bacteria (10 mL of bottom agar media [agar 12 g/L] and 6 mL of upper semi-agar media [6 g/L] with 100 &#181;L of bacteria [0.5 McFarland]) to be tested.</li>
		<li>Make a double-layer incubated plate for each strain to be tested. Leave a gap under the lid of the double-layered plate and blow to dry the agar surface in the biosafety cabinet.</li>
	</ol>
	</li>
	<li>Screening test
	<ol>
		<li>Place the prepared phage seed block and double-layer plate on the mobile carrier of the 96-dot matrix inoculator, and transfer all phage inocula to the semi-agar surface. Continue the cycles until all tested strains are completed.</li>
		<li>Let the inoculated double-layer plates remain at RT until the moisture in the inoculum spots is absorbed fully into the semi-agar.</li>
		<li>Invert the plates and incubate under suitable conditions for the tested strains for 4-6 h to ensure that clear lytic spots are formed.</li>
	</ol>
	</li>
	<li>Analyzing data
	<ol>
		<li>Obtain and save the image of the experimental result of each double-layer plate by the image acquisition converter (steps 1.5.4-1.5.6).</li>
		<li>Record the number and morphologies of the different shapes of spots into a spreadsheet based on the obtained images, and calculate the respective proportions of the different kinds of phages.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Ramanan, L., 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=Antimicrobial+resistance-the+need+for+global+solutions.">Antimicrobial resistance-the need for global solutions.</a> The Lancet Infectious Diseases. 13 (12), 1057-1098 (2013).</li><li>Xiaonan, Z., Qing, Z., Thomas, S. P., Yuqing, L., Martha, R. J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=inPhocus:+Perspectives+of+the+application+of+bacteriophages+in+poultry+and+aquaculture+industries+based+on+Varms+in+China.">inPhocus: Perspectives of the application of bacteriophages in poultry and aquaculture industries based on Varms in China.</a> PHAGE: Therapy, Applications, and Research. 2 (2), 69-74 (2021).</li><li>CLSI. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Performance Standards for Antimicrobial Disk Susceptibility Tests. CLSI document M100. , (2022).</li><li>Yuqing, L., 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> Antimicrobial Sensitivity Testing Standard of EUCAST. , (2017).</li><li>Barnini, 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+new+rapid+method+for+direct+antimicrobial+susceptibility+testing+of+bacteria+from+positive+blood+cultures.">A new rapid method for direct antimicrobial susceptibility testing of bacteria from positive blood cultures.</a> BMC Microbiology. 16 (1), 185-192 (2016).</li><li>H&#246;ring, S., Massarani, A. S., L&#246;ffler, B., R&#246;del, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+antimicrobial+susceptibility+testing+in+blood+culture+diagnostics+performed+by+direct+inoculation+using+the+VITEK&#174;-2+and+BD+PhoenixTM+platforms.">Rapid antimicrobial susceptibility testing in blood culture diagnostics performed by direct inoculation using the VITEK&#174;-2 and BD PhoenixTM platforms.</a> European Journal of Clinical Microbiology &amp; Infectious Diseases. 38 (3), 471-478 (2019).</li><li>Dupuis, G. <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+the+Cobasbact+automated+antimicrobial+susceptibility+testing+system.">Evaluation of the Cobasbact automated antimicrobial susceptibility testing system.</a> European Journal of Clinical Microbiology &amp; Infectious Diseases. 4 (2), 119-122 (1985).</li><li>Liu, Y., 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+system+of+bacterial+antimicrobial+resistance+detection+and+its+operation+method.">A system of bacterial antimicrobial resistance detection and its operation method.</a> China Patent. , (2019).</li><li>Liu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high+throughput+test+plate+for+screening+bacteriophage+of+zoonotic+pathogens+and+its+application.">A high throughput test plate for screening bacteriophage of zoonotic pathogens and its application.</a> China Patent. , (2022).</li><li>Adams, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Bacteriophages. , (1959).</li><li>Nair, A., Ghugare, G. S., Khairnar, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+appraisal+of+bacteriophage+isolation+techniques+from+environment.">An appraisal of bacteriophage isolation techniques from environment.</a> Microbial Ecology. 83 (3), 519-535 (2022).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Shandong veterinary antibiotic resistance system. , (2023).</li><li>Ming, H., 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+the+results+of+96-dot+agar+dilution+method+and+broth+microdilution+method.">Comparison of the results of 96-dot agar dilution method and broth microdilution method.</a> Chinese Journal of Antibiotics. 43 (6), 729-733 (2018).</li><li>Laxminarayan, R., Klugman, K. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Communicating+trends+in+resistance+using+a+drug+resistance+index.">Communicating trends in resistance using a drug resistance index.</a> BMJ Open. 1 (2), e000135 (2011).</li><li>Chen, Y., 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=Assessing+antibiotic+therapy+effectiveness+against+the+major+bacterial+pathogens+in+a+hospital+using+an+integrated+index.">Assessing antibiotic therapy effectiveness against the major bacterial pathogens in a hospital using an integrated index.</a> Future Microbiology. 12, 853-866 (2017).</li><li>Ciccolini, M., Spoorenberg, V., Geerlings, S. E., Prins, J. M., Grundmann, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+an+index-based+approach+to+assess+the+population-level+appropriateness+of+empirical+antibiotic+therapy.">Using an index-based approach to assess the population-level appropriateness of empirical antibiotic therapy.</a> Journal of Antimicrobial Chemotherapy. 70 (1), 286-293 (2015).</li><li>Yanbo, L., 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=Preliminary+application+of+inoculation+system+for+high-throughput+drug+susceptibility+test.">Preliminary application of inoculation system for high-throughput drug susceptibility test.</a> China Poultry. 42 (6), 52-57 (2020).</li></ol>

Yuqing Liu et al. have filed Chinese patents for the 96-dot matrix inoculator and image acquisition converter and their applications (Patent number ZL 201610942866.3 and Patent number ZL 201910968255.X).

The agar dilution method has been well-established and used widely. The principle of the high-throughput AST system was that of the agar dilution method. One of the critical steps within the protocol was the accurate high throughput transfer of 96 inocula at one time, which was performed multiple times in a row. To complete this critical step, the pins of the 96-dot matrix inoculator were uniform and very smooth. The natural deposition of each pin was a volume of approximately 2 &#181;L, which aggregated into small dropl...

As antimicrobial agents have been widely used to prevent bacterial infectious diseases, antimicrobial resistance (AMR) has become a global public health problem1. Combating AMR is the current main mission of monitoring AMR of epidemiological pathogens and synergistic therapy of sensitive antimicrobial agents and lytic bacteriophages2.
In vitro antimicrobial sensitivity testing (AST) is the mainstay for monitoring therapy and detecting the level of AMR. It is an important part of antimicrobial pharmacology and the critical basis for clinical medication. The Clinical and Laboratory Standards Institute (CLSI) of the United States and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) have formulated and revised international criteria of AST and continuously modified and supplemented AST methods and the breakpoints to determine the MIC of one certain &#34;organism-antimicrobial agent&#34; combination as sensitive (S), resistant (R) or intermediate (I)3,4.
From the 1980s to the 1990s, automatic micro broth dilution instruments were rapidly developed and applied to clinical practice, with examples including Alfred 60AST, VITEK System, PHOENIXTM, and Cobasbact5,6,7. However, these instruments were expensive, required high-cost consumables, and their detection ranges were designed for clinical patient medication5,6,7. For these reasons, they are not suitable for veterinary clinical examination and detection of large quantities of highly resistant strains. In this study, an intelligent high-throughput AST/phage screening system, including a 96-dot matrix inoculator (Figure 1), image acquisition converter (Figure 2), and corresponding software8, was developed to conduct AST for a batch of bacteria strains against multiple antimicrobial agents at one time by the agar dilution method. Moreover, the system was also used to detect and analyze the lysis patterns of phages against antimicrobial-resistant bacteria9, and lytic phages were selected efficiently from the phage library. This system was found to be efficient, affordable, and easy to operate.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64785/64785fig01.jpg" /> 
Figure 1: Structural diagram of the 96-dot matrix inoculator. 1: Inoculation pin plate; 2: Mobile carrier; 3: Seed block; 4: Incubated plate; 5: Base; 6: Operating handle; 7: Limit pin. <a href="https://www.jove.com/files/ftp_upload/64785/64785fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64785/64785fig02.jpg" /> 
Figure 2: Structural diagram of the image acquisition converter. 1: Shell; 2: Display screen; 3: Image acquisition room; 4: Detection board base; 5: Detection board in and out of warehouse; 6: Control board; 7: Image acquisition conversion device; 8: Light source; 9: Image scanner. <a href="https://www.jove.com/files/ftp_upload/64785/64785fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>96 well&#160; culture plate</td>
			<td>Beijing lanjieke Technology Co., Ltd</td>
			<td>11510</td>
			<td></td>
		</tr>
		<tr>
			<td>96-dot matrix AST image acquisition system</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>96-dot matrix inoculator&#160;</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>N/A</td>
			<td>Patented product</td>
		</tr>
		<tr>
			<td>Agar</td>
			<td>Qingdao hi tech Industrial Park Haibo Biotechnology Co., Ltd</td>
			<td>HB8274-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Amikacin&#160;</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>A857053</td>
			<td></td>
		</tr>
		<tr>
			<td>Amoxicillin</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>A822839</td>
			<td></td>
		</tr>
		<tr>
			<td>Ampicillin</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>A830931</td>
			<td></td>
		</tr>
		<tr>
			<td>Analytical balance</td>
			<td>Sartorius</td>
			<td>BSA224S</td>
			<td></td>
		</tr>
		<tr>
			<td>Automated calculation software for Lar index of AMR</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>Bacteria Salmonella strains</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>N/A</td>
			<td>Animal origin</td>
		</tr>
		<tr>
			<td>Bacterial resistance Lar index certification management system V1.0</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>Ceftiofur</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>C873619</td>
			<td></td>
		</tr>
		<tr>
			<td>Ciprofloxacin</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>C824343</td>
			<td></td>
		</tr>
		<tr>
			<td>Clavulanic acid</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>C824181</td>
			<td></td>
		</tr>
		<tr>
			<td>Clean worktable</td>
			<td>Suzhou purification equipment Co., Ltd</td>
			<td>SW-CJ-2D</td>
			<td></td>
		</tr>
		<tr>
			<td>Colistin sulfate</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>C805491</td>
			<td></td>
		</tr>
		<tr>
			<td>Culture plate</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>N/A</td>
			<td>Patented product</td>
		</tr>
		<tr>
			<td>Doxycycline</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>D832390</td>
			<td></td>
		</tr>
		<tr>
			<td>Enrofloxacin</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>E809130</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter 0.22 &#956;m</td>
			<td>Millipore</td>
			<td>SLGP033RB</td>
			<td></td>
		</tr>
		<tr>
			<td>Florfenicol</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>F809685</td>
			<td></td>
		</tr>
		<tr>
			<td>Gentamicin</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>G810322</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass bottle 50 mL</td>
			<td>Xuzhou Qianxing Glass Technology Co., Ltd</td>
			<td>QX-7</td>
			<td></td>
		</tr>
		<tr>
			<td>High-throughput resistance detection system V1.0</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>Image acquisition converter</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>N/A</td>
			<td>Patented product</td>
		</tr>
		<tr>
			<td>Meropenem</td>
			<td>Shanghai McLean Biochemical Technology Co., Ltd</td>
			<td>M861173</td>
			<td></td>
		</tr>
		<tr>
			<td>Mueller-Hinton agar</td>
			<td>Qingdao hi tech Industrial Park Haibo Biotechnology Co., Ltd</td>
			<td>HB6232</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish 60 mm x 15 mm</td>
			<td>Qingdao Jindian biochemical equipment Co., Ltd</td>
			<td>16021-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish 90 mm x 15 mm</td>
			<td>Qingdao Jindian biochemical equipment Co., Ltd</td>
			<td>16001-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Salmonella phages</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Shaker incubator</td>
			<td>Shanghai Minquan Instrument Co., Ltd</td>
			<td>MQD-S2R</td>
			<td></td>
		</tr>
		<tr>
			<td>Turbidimeter</td>
			<td>Shanghai XingBai Biotechnology Co., Ltd</td>
			<td>F-TC2015</td>
			<td></td>
		</tr>
		<tr>
			<td>Varms base type library system V1.0</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>Vertical high-pressure steam sterilizer</td>
			<td>Shanghai Shen&#39;an medical instrument factory</td>
			<td>LDZX-75L</td>
			<td></td>
		</tr>
		<tr>
			<td>Veterinary pathogen resistance testing management system</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
		<tr>
			<td>Veterinary resistance cloud monitoring and phage control platform V1.0</td>
			<td>Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences</td>
			<td>In-house software copyright</td>
			<td></td>
		</tr>
	</tbody>
</table>

application of the intelligent high-throughput antimicrobial sensitivity testing/phage screening system and lar index of antimicrobial resistance

To improve the efficiency of antimicrobial susceptibility testing (AST) and phage high-throughput screening for resistant bacteria and to reduce the detection cost, an intelligent high-throughput AST/phage screening system, including a 96-dot matrix inoculator, image acquisition converter, and corresponding software, was developed according to AST criteria and the breakpoints of resistance (R) formulated by the Clinical &amp; Laboratory Standards Institute (CLSI). AST and statistics of minimum inhibitory concentration (MIC) distributions (from R/8 to 8R) of 1,500 Salmonella strains isolated from poultry in Shandong, China, against 10 antimicrobial agents were carried out by the intelligent high-throughput AST/phage screening system. The Lar index, meaning "less antibiosis, less resistance and residual until little antibiosis", was obtained by calculating the weighted average of each MIC and dividing by R. This approach improves accuracy in comparison with using the prevalence of resistance to characterize the antimicrobial resistance (AMR) degree of highly resistant strains. For the strains of Salmonella with high AMR, lytic phages were efficiently screened from the phage library by this system, and the lysis spectrum was computed and analyzed. The results showed that the intelligent high-throughput AST/phage screening system was operable, accurate, highly efficient, inexpensive, and easy to maintain. Combined with the Shandong veterinary antimicrobial resistance monitoring system, the system was suitable for scientific research and clinical detection related to AMR.

Following the protocol of the intelligent high-throughput AST system, its application was illustrated by Salmonella from poultry in Shandong, China, as an example.
The growth of Salmonella strains on agar plates with ampicillin (R of 32 &#181;g/mL) at concentrations from 2 to 256 &#181;g/mL determined by the image acquisition converter is shown in Figure 3. The horizontal 1st well A1 was the negative control and showed no colony growth...

Watch this Scientific Journal Video about Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance at JoVE.com

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance

Here we introduce the principle, structure, and instruction of the intelligent high-throughput antimicrobial sensitivity testing/phage screening system. Its application is illustrated by using Salmonella isolated from poultry in Shandong, China, as an example. The Lar index is calculated, and its significance in evaluating antimicrobial resistance is discussed comprehensively.

To improve the efficiency of antimicrobial susceptibility testing (AST) and phage high-throughput screening for resistant bacteria and to reduce the ...

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1.1K Views.  Key Laboratory of Livestock and Poultry Multi-omics of MARA. Here we introduce the principle, structure, and instruction of the intelligent high-throughput antimicrobial sensitivity testing/phage screening system. Its application is illustrated by using Salmonella isolated from poultry in Shandong, China, as an example. The Lar index is calculated, and its significance in evaluating antimicrobial resistance is discussed comprehensively.

Video: Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance

Determination of Microbial Extracellular Enzyme Activity in Waters, Soils, and Sediments using High Throughput Microplate Assays

Much of the nutrient cycling and carbon processing in natural environments occurs through the activity of extracellular enzymes released by microorganisms. Thus, measurement of the activity of these extracellular enzymes can give insights into the rates of ecosystem level processes, such as organic matter decomposition or nitrogen and phosphorus mineralization. Assays of extracellular enzyme activity in environmental samples typically involve exposing the samples to artificial colorimetric or fluorometric substrates and tracking the rate of substrate hydrolysis. Here we describe microplate based methods for these procedures that allow the analysis of large numbers of samples within a short time frame. Samples are allowed to react with artificial substrates within 96-well microplates or deep well microplate blocks, and enzyme activity is subsequently determined by absorption or fluorescence of the resulting end product using a typical microplate reader or fluorometer. Such high throughput procedures not only facilitate comparisons between spatially separate sites or ecosystems, but also substantially reduce the cost of such assays by reducing overall reagent volumes needed per sample.

Microplate based procedures are described for the colorimetric or fluorometric analysis of extracellular enzyme activity. These procedures allow for the rapid assay of such activity in large numbers of environmental samples within a manageable time frame.

Much of the nutrient cycling and carbon  processing in natural environments occurs through the activity of extracellular  enzymes released by ...

High-throughput Fluorometric Measurement of Potential Soil Extracellular Enzyme Activities

Microbes in soils and other environments produce extracellular enzymes to depolymerize and hydrolyze organic macromolecules so that they can be assimilated for energy and nutrients. Measuring soil microbial enzyme activity is crucial in understanding soil ecosystem functional dynamics. The general concept of the fluorescence enzyme assay is that synthetic C-, N-, or P-rich substrates bound with a fluorescent dye are added to soil samples. When intact, the labeled substrates do not fluoresce. Enzyme activity is measured as the increase in fluorescence as the fluorescent dyes are cleaved from their substrates, which allows them to fluoresce. Enzyme measurements can be expressed in units of molarity or activity. To perform this assay, soil slurries are prepared by combining soil with a pH buffer. The pH buffer (typically a 50 mM sodium acetate or 50 mM Tris buffer), is chosen for the buffer&#39;s particular acid dissociation constant (pKa) to best match the soil sample pH. The soil slurries are inoculated with a nonlimiting amount of fluorescently labeled (i.e. C-, N-, or P-rich) substrate. Using soil slurries in the assay serves to minimize limitations on enzyme and substrate diffusion. Therefore, this assay controls for differences in substrate limitation, diffusion rates, and soil pH conditions; thus detecting potential enzyme activity rates as a function of the difference in enzyme concentrations (per sample).
Fluorescence enzyme assays are typically more sensitive than spectrophotometric (i.e. colorimetric) assays,&#160;but can suffer from interference caused by impurities and the instability of many fluorescent compounds when exposed to light; so caution is required when handling fluorescent substrates. Likewise, this method only assesses potential enzyme activities under laboratory conditions when substrates are not limiting. Caution should be used when interpreting the data representing cross-site comparisons with differing temperatures or soil types, as in situ soil type and temperature can influence enzyme kinetics.

To measure potential rates of soil extracellular enzyme activities, synthetic substrates that are bound to a fluorescent dye are added to soil samples. Enzyme activity is measured as the fluorescent dye is released from the substrate by an enzyme-catalyzed reaction, where higher fluorescence indicates more substrate degradation.

Microbes in soils and other environments produce extracellular enzymes to depolymerize and hydrolyze organic macromolecules so that they can be ...

Optimized Negative Staining: a High-throughput Protocol for Examining Small and Asymmetric Protein Structure by Electron Microscopy

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of natural proteins have a molecular mass between 40 - 200 kDa1,2, a robust and high-throughput method with a nanometer resolution capability is needed. Negative staining (NS) electron microscopy (EM) is an easy, rapid, and qualitative approach which has frequently been used in research laboratories to examine protein structure and protein-protein interactions. Unfortunately, conventional NS protocols often generate structural artifacts on proteins, especially with lipoproteins that usually form presenting rouleaux artifacts. By using images of lipoproteins from cryo-electron microscopy (cryo-EM) as a standard, the key parameters in NS specimen preparation conditions were recently screened and reported as the optimized NS protocol (OpNS), a modified conventional NS protocol 3 . Artifacts like rouleaux can be greatly limited by OpNS, additionally providing high contrast along with reasonably high&#8208;resolution (near 1 nm) images of small and asymmetric proteins. These high-resolution and high contrast images are even favorable for an individual protein (a single object, no average) 3D reconstruction, such as a 160 kDa antibody, through the method of electron tomography4,5. Moreover, OpNS can be a high&#8208;throughput tool to examine hundreds of samples of small proteins. For example, the previously published mechanism of 53 kDa cholesteryl ester transfer protein (CETP) involved the screening and imaging of hundreds of samples 6. Considering cryo-EM rarely successfully images proteins less than 200 kDa has yet to publish any study involving screening over one hundred sample conditions, it is fair to call OpNS a high-throughput method for studying small proteins. Hopefully the OpNS protocol presented here can be a useful tool to push the boundaries of EM and accelerate EM studies into small protein structure, dynamics and mechanisms.

More than half of proteins are small proteins (molecular mass &#60;200 kDa) that are challenging for both electron microscope imaging and three-dimensional reconstructions. Optimized negative staining is a robust and high-throughput protocol to obtain high contrast and relatively high resolution (~1 nm) images of small asymmetric proteins or complexes under different physiological conditions.

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of ...

Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies

The two-spotted spider mite, Tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with more than 150 of economic value. It is a major pest of greenhouse crops, especially in Solanaceae and Cucurbitaceae (e.g., tomatoes, eggplants, peppers, cucumbers, zucchini) and greenhouse ornamentals (e.g., roses, chrysanthemum, carnations), annual field crops (such as maize, cotton, soybean, and sugar beet), and in perennial cultures (alfalfa, strawberries, grapes, citruses, and plums)1,2. In addition to the extreme polyphagy that makes it an important agricultural pest, T. urticae has a tendency to develop resistance to a wide array of insecticides and acaricides that are used for its control3-7.
T. urticae is an excellent experimental organism, as it has a rapid life cycle (7 days at 27 &#176;C) and can be easily maintained at high density in the laboratory. Methods to assay gene expression (including in situ hybridization and antibody staining) and to inactivate expression of spider mite endogenous genes using RNA interference have been developed8-10. Recently, the whole genome sequence of T. urticae has been reported, creating an opportunity to develop this pest herbivore as a model organism with equivalent genomic resources that already exist in some of its host plants (Arabidopsis thaliana and the&#160;tomato Solanum lycopersicum)11. Together, these&#160;model organisms could provide insights into molecular bases of plant-pest interactions.
Here, an efficient method for quick and easy collection of a large number of adult female mites, their application on an experimental plant host, and the assessment of the plant damage due to spider mite feeding are described. The presented protocol enables fast and efficient collection of hundreds of individuals at any developmental stage (eggs, larvae, nymphs, adult males, and females) that can be used for subsequent experimental application.

Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies

Protocols for efficient preparation of homogenous samples of spider mites, infestation of experimental plants, and assessment of plant damage, as required for studies of plant-pest interaction were developed.

The two-spotted spider mite, Tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with ...

Modifying the Bank Erosion Hazard Index (BEHI) Protocol for Rapid Assessment of Streambank Erosion in Northeastern Ohio

Understanding the source of pollution in a stream is vital to preserving, restoring, and maintaining the stream&#8217;s function and habitat it provides. Sediments from highly eroding streambanks are a major source of pollution in a stream system and have the potential to jeopardize habitat, infrastructure, and stream function. Watershed management practices throughout the Cleveland Metroparks attempt to locate and inventory the source and rate the risk of potential streambank erosion to assist in formulating effect stream, riparian, and habitat management recommendations. The Bank Erosion Hazard Index (BEHI), developed by David Rosgen of Wildland Hydrology is a fluvial geomorphic assessment procedure used to evaluate the susceptibility of potential streambank erosion based on a combination of several variables that are sensitive to various processes of erosion. This protocol can be time consuming, difficult for non-professionals, and confined to specific geomorphic regions. To address these constraints and assist in maintaining consistency and reducing user bias, modifications to this protocol include a &#8220;Pre-Screening Questionnaire&#8221;, elimination of the Study Bank-Height Ratio metric including the bankfull determination, and an adjusted scoring system. This modified protocol was used to assess several high priority streams within the Cleveland Metroparks. The original BEHI protocol was also used to confirm the results of the modified BEHI protocol. After using the modified assessment in the field, and comparing it to the original BEHI method, the two were found to produce comparable BEHI ratings of the streambanks, while significantly reducing the amount of time and resources needed to complete the modified protocol.

Modifying the Bank Erosion Hazard Index BEHI Protocol for Rapid Assessment of Streambank Erosion in Northeastern Ohio

Streambank erosion potential can be evaluated and ranked using David Rosgen&#8217;s Bank Erosion Hazard Index (BEHI), however this protocol has significant limitations. Here we present protocol modifications to address time constraints, allow nonprofessionals to complete accurate assessments, and account for non-alluvial stream conditions in Northeast Ohio.

Understanding the source of pollution in a stream is vital to preserving, restoring, and maintaining the stream&#8217;s function and habitat it provides. ...

Semi-High Throughput Screening for Potential Drought-tolerance in Lettuce (Lactuca sativa) Germplasm Collections

This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits.

Semi-High Throughput Screening for Potential Drought-tolerance in Lettuce Lactuca sativa Germplasm Collections

This protocol was developed to screen a large germplasm collection of the leafy vegetable lettuce (Lactuca sativa L.) for drought-tolerance, in order to identify a small candidate pool of lettuce for use in physiological, molecular, and genetic studies to identify underlying drought-tolerance traits along with breeding programs.

This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely ...

High-throughput Screening of Recalcitrance Variations in Lignocellulosic Biomass: Total Lignin, Lignin Monomers, and Enzymatic Sugar Release

The conversion of lignocellulosic biomass to fuels, chemicals, and other commodities has been explored as one possible pathway toward reductions in the use of non-renewable energy sources. In order to identify which plants, out of a diverse pool, have the desired chemical traits for downstream applications, attributes, such as cellulose and lignin content, or monomeric sugar release following an enzymatic saccharification, must be compared. The experimental and data analysis protocols of the standard methods of analysis can be time-consuming, thereby limiting the number of samples that can be measured. High-throughput (HTP) methods alleviate the shortcomings of the standard methods, and permit the rapid screening of available samples to isolate those possessing the desired traits. This study illustrates the HTP sugar release and pyrolysis-molecular beam mass spectrometry pipelines employed at the National Renewable Energy Lab. These pipelines have enabled the efficient assessment of thousands of plants while decreasing experimental time and costs through reductions in labor and consumables.

Plant cell wall structure and chemistry traits are evaluated to identify ideal feedstocks for biofuels and bio-materials. Standard methods have limitations when applied to large data sets. These high-throughput pretreatment, enzyme saccharification, and pyrolysis-molecular beam mass spectrometry methods compare large numbers of biomass samples with decreased experimental time and cost.

The conversion of lignocellulosic biomass to fuels, chemicals, and other commodities has been explored as one possible pathway toward reductions in the ...

The Effect of the Application of Thyme Essential Oil on Microbial Load During Meat Drying

Meat is a high protein meal that is used in the preparation of jerky, a popular food snack, where preservation and safety are important. To assure food safety and to extend the shelf life of meat and meat products, the use of either synthetic or natural preservatives have been applied to control and eliminate foodborne bacteria. A growing interest in the application of natural food additives for meat has increased. Microorganisms, such as Escherichia coli, contaminate meat and meat products, causing foodborne illnesses. Therefore, it is necessary to improve the meat conservation process. However, the use of essential oils when the meat is being dried has not been deeply studied. In this regard, there is an opportunity to increase the value of dried meat and reduce the risk of foodborne illnesses by applying essential oils during the drying process. In this protocol, we present a novel method of applying thyme essential oil (TEO) during meat drying, specifically in vapor form directly in a drying chamber. For evaluation, we use Minimal Inhibitory Concentration (MIC) to detect the number of harmful bacteria in the treated samples compared to raw samples. The preliminary results show that this method is a viable and alternative option to synthetic preservatives and that it significantly reduces microbial load in dried meat.

Microorganisms such as Escherichia coli that contaminate meat products cause foodborne illnesses. The use of essential oils in the meat drying process has not been deeply studied. Here, we present a novel method of applying thyme essential oil to meat during drying to reduce the microbial load in dried meat.

Meat is a high protein meal that is used in the preparation of jerky, a popular food snack, where preservation and safety are important. To assure food ...

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current measures to combat such pathogens have proved too conservative and, thus, not sufficiently effective, and they can potentially pose environmental risks. Therefore, it is extremely necessary to identify host-resistance factors to assist in controlling plant diseases naturally through the identification of resistant germplasm, the isolation and characterization of resistance genes, and the molecular breeding of resistant cultivars. In this regard, there is need to establish an accurate, rapid, and large-scale inoculation method to breed and develop plant resistance genes. The rice blast fungal pathogen Magnaporthe grisea causes severe disease symptoms and yield losses. Recently, M. grisea has emerged as a model organism for studying the mechanisms of plant-fungal pathogen interactions. Hence, we report the development of a plant virulence test method that is specific for M. grisea. This method provides for both spray inoculation with a conidial suspension and wounding inoculation with mycelium cubes or droplets of conidial suspension. The key step of the wounding inoculation method for detached rice leaves is to make wounds on plant leaves, which avoids any interference caused by host penetration resistance. This spray/wounding protocol contributes to the rapid, accurate, and large-scale screening of the pathotypes of M. grisea isolates. This integrated and systematic plant infection method will serve as an excellent starting point for gaining a broad perspective of issues in plant pathology.

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Here, we present a protocol to test plant virulence with the plant pathogen Magnaporthe grisea. This report will contribute to the large-scale screening of the pathotypes of fungi isolates and serve as an excellent starting point for understanding the resistant mechanisms of plants during molecular breeding.

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current ...

High-throughput, Microscale Protocol for the Analysis of Processing Parameters and Nutritional Qualities in Maize (Zea mays L.)

Maize is an important grain crop in the United States and worldwide. However, maize grain must be processed prior to human consumption. Furthermore, whole grain composition and processing characteristics vary among maize hybrids and can impact the quality of the final processed product. Therefore, in order to produce healthier processed food products from maize, it is necessary to know how to optimize processing parameters for particular sets of germplasm to account for these differences in grain composition and processing characteristics. This includes a better understanding of how current processing techniques impact the nutritional quality of the final processed food product. Here, we describe a microscale protocol that both simulates the processing pipeline to produce cornflakes from large flaking grits and allows for the processing of multiple grain samples simultaneously. The flaking grits, the intermediate processed products, or final processed product, as well as the corn grain itself, can be analyzed for nutritional content as part of a high-throughput analytical pipeline. This procedure was developed specifically for incorporation into a maize breeding research program, and it can be modified for other grain crops. We provide an example of the analysis of insoluble-bound ferulic acid and p-coumaric acid content in maize. Samples were taken at five different processing stages. We demonstrate that sampling can take place at multiple stages during microscale processing, that the processing technique can be utilized in the context of a specialized maize breeding program, and that, in our example, most of the nutritional content was lost during food product processing.

High-throughput, Microscale Protocol for the Analysis of Processing Parameters and Nutritional Qualities in Maize Zea mays L.

Here, we present a microscale protocol for processing grain samples and for incorporating this microscale approach into a high-throughput analytical pipeline. This is a higher throughput adaptation of currently available protocols.

Maize is an important grain crop in the United States and worldwide. However, maize grain must be processed prior to human consumption. Furthermore, whole ...