Microbiology Methods for ERP Review 3-2020

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GENE-UP SLM Matrix Extension

June 19, 2017

the method had 9 out of 20 samples presumptive and confirmed (by both alternative and reference 1 methods) positives and 7 out of 20 for the MLG reference method. There was no significant difference 2 between the GENE ‐ UP Salmonella detection assay presumptive and the confirmed or between the GENE ‐ 3 UP method and the reference method results using probability of detection (POD) statistical model (see 4 Tables 4 ‐ 6 5 6 Raw ground chicken: Raw ground chicken had >2500 CFU/g of background organisms and was negative for 7 natural occurring Salmonella . Analysis was performed on three levels of S. enterica serovar Enteritidis 8 inoculation: 0, 0.41 (0.11, 0.50) and 4 (2.45, >10) MPN/test portion for the GENE ‐ UP and the MLG reference 9 methods using both BPW and mTSB primary enrichment media. The un ‐ inoculated samples resulted in 0 10 positives out of 5 replicates for both methods (BPW and mTSB). The 4 CFU level samples resulted in 5 11 positives out of 5 replicates for both methods (BPW and mTSB). For the 0.41 CFU level of inoculation, the 12 method had 5 out of 20 samples presumptive and confirmed (by both alternative and reference methods) 13 positives for both media and 5 out of 20 for the MLG reference method. There was no significant difference 14 between the GENE ‐ UP Salmonella detection assay presumptive and the confirmed or between the GENE ‐ 15 UP method and the reference method results using probability of detection (POD) statistical model (see 16 Tables 4 ‐ 6). 17 18 Beef trim: Beef trim had >2500 CFU/g of background organisms and was negative for natural occurring 19 Salmonella . Analysis was performed on three levels of S.enterica serovar Hadar inoculation: 0, 0.60 (0.32, 20 1.18) and >10 (2, >10) MPN/test portion for the GENE ‐ UP and the MLG reference methods using both BPW 21 and mTSB primary enrichment media. The un ‐ inoculated samples resulted in 0 positives out of 5 replicates 22 for both methods (BPW and mTSB, 10 and 24 h). The >10 CFU level samples resulted in 5 positives out of 5 23 replicates for both methods (BPW and mTSB, 10 and 24 h). For the 0.60 CFU level of inoculation, the 24 method had 14 out of 20 samples presumptive and confirmed (by both alternative and reference methods) 25 positives using BPW after both 10 and 24 h. For the 0.60 CFU level of inoculation, the method had 11 out of 26 20 samples presumptive and confirmed (by both alternative and reference methods) positives using mTSB 27 after both 10 and 24 h. There were 9 out of 20 positives for the MLG reference method. There was no 28 significant difference between the GENE ‐ UP Salmonella detection assay presumptive and the confirmed or 29 between the GENE ‐ UP method and the reference method results using probability of detection (POD) 30 statistical model (see Tables 4 ‐ 6). 31 32 Raw ground pork: Raw ground pork had >2500 CFU/g of background organisms and was negative for 33 natural occurring Salmonella . Analysis was performed on three levels of S.enterica serovar Houtenae 34 inoculation: 0, 0.56 (0.28, 1.37) and >10 (4, >10) MPN/test portion for the GENE ‐ UP and the MLG reference 35 methods using both BPW and mTSB primary enrichment media. The un ‐ inoculated samples resulted in 0 36 positives out of 5 replicates for both methods (BPW and mTSB, 10 and 24 h). The >10 CFU level samples 37 resulted in 5 positives out of 5 replicates for both methods (BPW and mTSB, 10 and 24 hours). For the 0.56 38 CFU level of inoculation, the method had 7 out of 20 samples presumptive and confirmed (by both 39 alternative and reference methods) positives using BPW after both 10 and 24 hours. For the 0.60 CFU level 40 of inoculation, the method had 5 out of 20 samples presumptive and confirmed (by both alternative and 41 reference methods) positives using mTSB after both 10 and 24 h. There were 3 out of 20 positives for the 42 MLG reference method. There was no significant difference between the GENE ‐ UP Salmonella detection 43 assay presumptive and the confirmed or between the GENE ‐ UP method and the reference method results 44 using probability of detection (POD) statistical model (see Tables 7 ‐ 9). 45 46 Raw ground bison: Raw ground bison had >2500 CFU/g of background organisms and was negative for 47 natural occurring Salmonella . Analysis was performed on three levels of S.enterica serovar Abortusequi 48 inoculation: 0, 0.29 (0.15, 0.711) and >10 (2, >10) MPN/test portion for the GENE ‐ UP and the MLG 49

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