ICMSF methods studies. IX. The influence of selective enrichment broths, differential planting media, and incubation temperatures on the detection of Salmonella in dried foods and feed ingredients

1977 ◽  
Vol 23 (9) ◽  
pp. 1225-1231 ◽  
Author(s):  
D. A. Gabis ◽  
J. H. Silliker
Keyword(s):  
Elevated Temperature ◽  
Brilliant Green ◽  
The Other ◽  
Feed Ingredients ◽  
Selective Media ◽  
Selective Enrichment ◽  
Enrichment Cultures ◽  
Incubation Temperatures ◽  
Better Than ◽  
Dried Foods

Ninety-eight dried foods and feed ingredients were analyzed for Salmonella using tetrathionate brilliant green (T) and selenite cystine (S) broths incubated at 35 and 43 °C. The four enrichment cultures for each sample were subcultured in duplicate onto brilliant green (BG), Salmonella–Shigella (SS), and bismuth sulfite (BS) agars, one plate of each being incubated at 35 °C, the other at 43 °C. Salmonellae were isolated from 44 of the 98 samples. Differences in the Salmonella recovery rates from the four selective enrichment conditions were not significant. However, there was a trend toward a higher proportion of Salmonella colonies on the selective media when the enrichment broths were incubated at 43 °C, although the differences were significant only with BG and SS subcultured from T. While the four enrichment systems were not significantly different, the trend toward a higher proportion of Salmonella colonies on the differential media subcultured from 43 °C enrichment broths indicates an advantage to incubation at the elevated temperature. Incubation of selective agars at 35 °C was best because at 43 °C Salmonella recovery was significantly reduced. Detection of salmonellae on BS was significantly better than on BG or SS.

ICMSF methods studies. VI. The influence of selective enrichment media and incubation temperatures on the detection of Salmonella in dried foods and feeds

1974 ◽  
Vol 20 (11) ◽  
pp. 1509-1511 ◽  
Author(s):  
D. A. Gabis ◽  
J. H. Silliker
Keyword(s):  
Brilliant Green ◽  
Selective Enrichment ◽  
Significant Difference ◽  
Low Moisture Foods ◽  
Incubation Temperatures ◽  
Red Meats ◽  
Enrichment Condition ◽  
By Products ◽  
Dried Foods

Recovery of Salmonella from low-moisture foods was studied using selective enrichment in tetrathionate brilliant green and selenite-cystine broths at 35C and 43C. A total of 1375 samples of dried dairy, soya, and rendered animal by-products were analyzed. All samples were preenriched before selective enrichment. No significant difference in recovery was detected between tetrathionate brilliant green and selenite cystine at either temperature, which is in contrast to our earlier findings with red meats. Pairing of enrichment conditions resulted in the detection of more positive samples than the use of any single enrichment condition.

ICMSF methods studies. V. The influence of selective enrichment media and incubation temperatures on the detection of salmonellae in raw frozen meats

1974 ◽  
Vol 20 (6) ◽  
pp. 813-816 ◽  
Author(s):  
J. H. Silliker ◽  
D. A. Gabis
Keyword(s):  
Brilliant Green ◽  
Medium Temperature ◽  
Raw Meat ◽  
Selective Media ◽  
Selective Enrichment ◽  
Incubation Temperatures

Sixty lots of frozen raw meat were analyzed for Salmonella using preenrichment in lactose broth followed by selective enrichment in four different selective broths, each incubated at 35C and 43C. Incubation at 43C resulted in detection of more Salmonella-containing samples. The highest recovery was observed with selenite cystine at 43C. However, the data indicated that two selective broths should be used for maximum recovery. Tetrathionate broth without brilliant green was inferior to the three other selective media used, both at 35C and 43C. Using selenite cystine, tetrathionate brilliant green, and selenite brilliant green sulfa broths, a number of medium/temperature pairs gave Salmonella recoveries approaching that obtained from all eight medium/temperature variables combined.

Preenrichment Conditions for Effective Recovery of Salmonella in Foods and Feed Ingredients

1979 ◽  
Vol 42 (2) ◽  
pp. 153-157 ◽  
Author(s):  
J. Y. D'AOUST ◽  
C. MAISHMENT
Keyword(s):  
Brilliant Green ◽  
False Negative ◽  
Food Samples ◽  
Contamination Level ◽  
Experimental Conditions ◽  
Feed Ingredients ◽  
Selective Enrichment ◽  
Negative Results ◽  
False Negative Results ◽  
The Cost

The efficacy of Clausen, EE, Eugon, GN, Tergitol 7, lactose and nutrient broths as Salmonella preenrichment media was evaluated using 165 food samples with an incident contamination level ranging from 1.5 to 460 salmonellae/100 g. Replicate food samples (100 g) were preenriched in each of seven media (900 ml) for 6 h and 24 h at 35 C; various amounts (10, 1.0 and 0.1 ml) of preenriched cultures were selectively enriched in tetrathionate brilliant green (43 C) and selenite cystine (35 C) broths and plated on bismuth sulfite and brilliant green sulfa agars. Short (6 h) and 24-h preenrichment conditions resulted in 26 (16%) and 8 (5%) false negative results, respectively. Recovery of Salmonella from 6-h but not 24-h preenrichment cultures also varied directly with the portion of culture inoculated into selective enrichment broths. None of the preenrichment media tested performed satisfactorily at 6 h of incubation where levels of recovery ranged from 32 to 62%; at 24 h, good recovery was obtained with all media (95 to 100%) except EE broth (74%). The incidence of competitive flora was significantly higher on selenite + brilliant green sulfa than on tetrathionate + bismuth sulfite; transfer volumes (10 and 1.0 ml) and preenrichment media did not contribute significantly to the presence of non-salmonellae on plating media. Characteristics of preenrichment media were found to be less critical than preenrichment incubation time for effective recovery of Salmonella in foods and feed ingredients. The use of 1.0- rather than 10-ml preenrichment transfer volume is indicated because it proved to be completely reliable under our experimental conditions and reduced the cost of analyses.

scholarly journals A comparison of the R25 modification of Rappaport's enrichment medium with strontium chloride B for salmonella isolation from sewage polluted natural water

1982 ◽  
Vol 89 (1) ◽  
pp. 111-117 ◽  
Author(s):  
R. W. S. Harvey ◽  
T. H. Price
Keyword(s):  
Elevated Temperature ◽  
Natural Water ◽  
The Other ◽  
Polluted Water ◽  
Strontium Chloride ◽  
Water Culture ◽  
Enrichment Medium ◽  
Peptone Water ◽  
Incubation Temperatures

SUMMARYThe relation of salmonella isolation efficiency and the size of inoculum introduced from a buffered peptone water culture of sewage polluted water into strontium chloride B medium was investigated. Two separate studies were made, one using enrichment at 37°C, the other at 43°C. From these trials, two inocula suitable for efficient salmonella isolation were determined. Using this information, strontium chloride B medium was compared with modified Rappaport's broth (R25). The inoculum used with R25 was 0·005 ml, determined in an earlier study. Two incubation temperatures were employed with strontium chloride enrichment (37 and 43°C). Rappaport's medium was incubated at 37°C only. Elevated temperature enrichment at 43°C improved the performance of strontium chloride B, but Rappaport's broth still gave significantly better results. This supports earlier studies on simplification of salmonella isolation and standardization of routine technique on a single enrichment medium: Rappaport broth (R25) incubated at 37°C.

Prevalence of Salmonella spp. and Yersinia enterocolitica in Finishing Swine at Canadian Abattoirs

1999 ◽  
Vol 62 (1) ◽  
pp. 22-25 ◽  
Author(s):  
ANN LETELLIER ◽  
S. MESSIER ◽  
S. QUESSY
Keyword(s):  
Confidence Interval ◽  
Yersinia Enterocolitica ◽  
Brilliant Green ◽  
Salmonella Spp ◽  
Selective Media ◽  
Selective Enrichment ◽  
Enrichment Technique

The prevalence of Salmonella spp. and Yersinia enterocolitica in finishing swine was evaluated using samples of cecal material. Samples were taken at six different slaughterhouses from 1420 healthy, 5-month-old pigs, raised by 223 producers in Québec (1009 samples), Ontario (283), and Manitoba, Canada (128). Two different broth media (Rappaport-Vassiliadis and Tetrathionate brilliant green) were used for the selective enrichment of Salmonella spp. The recovery of Y. enterocolitica was done by a cold enrichment technique, followed by plating on a selective media (cefsulodin-irgasan-novobiocin agar). Prevalence (with a 95% confidence interval) of Salmonella spp. and Y. enterocolitica were, respectively, 5.2% (4.0 to 6.4%) and 20.9% (18.8 to 23.0%). Overall, 24.6% of the animals tested were positive for one or both of these pathogens. Since only a few herds (2.8%) appeared to be highly contaminated by Salmonella spp., efforts should be undertaken in priority to control this pathogen in those herds.

Inadequacy of Small Transfer Volume and Short (6 h) Selective Enrichment for the Detection of Foodborne Salmonella

1992 ◽  
Vol 55 (5) ◽  
pp. 326-328 ◽  
Author(s):  
J.-Y. D'AOUST ◽  
A. M. SEWELL ◽  
E. DALEY
Keyword(s):  
Brilliant Green ◽  
Volume Ratio ◽  
Selective Enrichment ◽  
Marginal Increase ◽  
Enrichment Cultures

The propensity of short (6 h) selective enrichment combined with a preenrichment to enrichment transfer volume ratio of 1:100 to provide greater method brevity could not be demonstrated. Inoculation of tetrathionate brilliant green (35 and 43°C), Rappaport-Vassiliadis (43°C), and selenite cystine (35°C) enrichment broths (9.0 ml) with 0.1 ml of preenrichment culture and incubation for 6 h identified, respectively, 107 (84.9%), 104 (82.5%), 112 (88.9%), and 113 (89.7%) of the 126 contaminated samples detected in the present study; homologous results with the 1.0-ml transfer volume showed a marginal increase in sensitivity. Recoveries of foodborne salmonellae with the standard (24-h) period of selective enrichment were generally transfer volume-independent and consistently exceeded that obtained with 6-h enrichment cultures. Results further underlined the importance of enrichment at an elevated (43°C) temperature for the effective repression of competitive microflora, and the facilitated isolation of Salmonella on plating media.

Performance of Four Selective Media for Enumerating Staphylococcus aureus in Corned Beef and in Cheese

1988 ◽  
Vol 51 (2) ◽  
pp. 87-88 ◽  
Author(s):  
K. RAYMAN ◽  
N. MALIK ◽  
G. JARVIS
Keyword(s):  
Staphylococcus Aureus ◽  
The Other ◽  
Selective Media ◽  
Strain Dependent ◽  
Better Than

The performance of four selective media for enumerating Staphylococcus aureus in artificially contaminated samples of corned beef was strain-dependent. Baird-Parker (BP), Kranep (KR), Mannitol Salt (MS) and Staphylococcus medium 110 (S110) performed equally well in enumerating an enterotoxin A producing strain, but KR and BP were significantly better than S110 in enumerating an enterotoxin D producing strain of S. aureus. In naturally contaminated cheese samples which abound with competing microorganisms, BP performed significantly better than the other three media.

Recovery of Salmonella from Fluid Milk

1988 ◽  
Vol 51 (5) ◽  
pp. 409-411 ◽  
Author(s):  
CLYDE R. WILSON ◽  
WALLACE H. ANDREWS ◽  
PAUL L. POELMA ◽  
VERNEAL R. BRUCE
Keyword(s):  
Brilliant Green ◽  
Incubation Temperature ◽  
Skim Milk ◽  
Selective Enrichment ◽  
Whole Milk ◽  
Peptone Water ◽  
Incubation Temperatures ◽  
Fluid Milk

Methodology was developed for isolation of Salmonella from skim milk, 2% fat milk, whole milk and buttermilk. Lactose broth, lactose broth plus brilliant green dye, buffered peptone water and each milk type plus brilliant green dye were evaluated as preenrichment broths. Incubation temperatures of 35 and 43°C were compared for use at the preenrichment stage. The recovery of Salmonella was determined after selective enrichment in selenite cystine, tetrathionate and Rappaport-Vassiliadis broths. Results indicated that fluid milk should be examined for Salmonella by being preenriched in lactose broth, subcultured to selenite cystine and tetrathionate broths and streaked to selective agars, with 35°C as the incubation temperature throughout the analysis.

Rapid Cultural Methods for Detection of Salmonella in Feeds and Feed Ingredients

1983 ◽  
Vol 46 (10) ◽  
pp. 851-855 ◽  
Author(s):  
J.-Y. D'AOUST ◽  
A. SEWELL ◽  
A. BOVILLE
Keyword(s):  
Standard Method ◽  
Brilliant Green ◽  
Nutrient Broth ◽  
Sample Analysis ◽  
Feed Ingredients ◽  
Selective Enrichment ◽  
Cultural Methods ◽  
Agar Media ◽  
Reduced Water ◽  
Single Medium

Efficacy of standard, 6-h standard and direct enrichment methods for detection of Salmonella in naturally contaminated feeds and feed ingredients was compared. Analysis by the standard method involved preenrichment of feed slurries in nutrient broth, selective enrichment in tetrathionate brilliant green (43°C) and selenite cystine (35°C), and isolation of presumptive isolates on bismuth sulfite and brilliant green sulfa agar media. Sample analysis by the 6-h standard method was identical to the above except that incubation of enrichment broths was reduced to 6 h; for direct enrichment. preenrichment in nutrient broth was omitted. Of 287 samples tested, 75 were found to contain salmonellae by the three methods combined. Ability of the standard and 6-h standard methods to identify the same 58 contaminated samples underlines the reliability of the 6-h standard method for the more rapid detection of Salmonella in animal feeds. Identification of 68 positive samples by direct enrichment presumably resulted from equilibration (3 to 4 h) of feed slurries at reduced water activity before analysis. Addition of novobiocin (40 μg/ml) to selective enrichment broths did not facilitate isolation of Salmonella through repression of competitive flora. Productivity of the six enrichment-plating combinations used in this study was comparable, and no single medium played a determinant role in recovery.

scholarly journals Studies on the isolation of Salmonella dublin

1975 ◽  
Vol 74 (3) ◽  
pp. 369-374 ◽  
Author(s):  
R. W. S. Harvey ◽  
T. H. Price
Keyword(s):  
Brilliant Green ◽  
The Other ◽  
Macconkey Agar ◽  
Salmonella Dublin ◽  
Selective Agar ◽  
Agar Media ◽  
Better Than

SUMMARYAbattoir drain swabs, bovine faeces and a few other veterinary samples were examined for the presence of Salmonella dublin. Three selective agar media and four enrichment broths were investigated. The two most efficient plating media were deoxycholate citrate agar and brilliant green MacConkey agar. Wilson and Blair's bismuth sulphite agar (de Loureiro's modification) was least successful. Selenite F broth, whether incubated at 37 or 43° C., was better than the other enrichment broths used which contained a triphenyl methane dye as one of the selective ingredients.

Sign in / Sign up

Export Citation Format

Share Document