Comparison of Conventional and Delayed Secondary Enrichment for Isolation of <i>Salmonella</i> Spp. from Swine Samples

Nietfeld, Jerome C.; Kelly, Barbara; Dritz, S. S.; Feder, Ingrid; Galland, John C.

doi:10.1177/104063879801000312

Cited by 16 publications

(17 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This result is consistent with the results from previous studies, which showed that DSE improves the recovery of Salmonella from poultry and poultry environments, 22,23,25 swine and swine environments, 5,16,18 and cattle. 17 The basis for the enhanced isolation of Salmonella with DSE is not clear.…”

Section: Discussionsupporting

confidence: 93%

Development of an antigen-capture monoclonal antibody–based enzyme-linked immunosorbent assay and comparison with culture for detection ofSalmonella entericaserovar Enteritidis in poultry hatchery environmental samples

et al. 2012

View full text Add to dashboard Cite

An antigen-capture enzyme-linked immunosorbent assay (ELISA) was developed for use as a presumptive screening test for detection of Salmonella enterica serovar Enteritidis and other group D Salmonella in poultry hatchery environments. A mixture of 2 monoclonal antibodies that recognize different forms of the lipopolysaccharide O-antigen was used for specific detection of group D Salmonella. The performance of the ELISA was evaluated in comparison to standard Salmonella culture procedures. Culture for each sample included nonselective enrichment with buffered peptone water and primary selective enrichment and delayed secondary enrichment with both tetrathionate and Rappaport-Vassiliadis broths. One thousand fifty-seven samples were collected from poultry hatcheries over a 5-year period (received in 85 submissions), and S. Enteritidis was recovered from 106 (10%) of them. The diagnostic sensitivity and specificity of the ELISA relative to culture were 97.2% and 99.6%, respectively, on a sample basis and were both 100% on a submission basis. Delayed secondary enrichment increased the number of S. Enteritidis culture and ELISA-positive samples as compared to nonselective enrichment and primary selective enrichment by 25%. A significantly higher (P < 0.05) number of S. Enteritidis culture- and ELISA-positive results were obtained from Rappaport-Vassiliadis broth than from tetrathionate broth or buffered peptone water cultures. The results indicate that this ELISA procedure may be useful for screening poultry hatchery environmental samples for the presence of S. Enteritidis.

show abstract

Section: Discussionsupporting

confidence: 93%

Development of an antigen-capture monoclonal antibody–based enzyme-linked immunosorbent assay and comparison with culture for detection ofSalmonella entericaserovar Enteritidis in poultry hatchery environmental samples

et al. 2012

View full text Add to dashboard Cite

show abstract

“…The primary objective of the studies reported here was to compare the protocols routinely used in the two laboratories which have collectively participated in most studies of Salmonella in swine in the USA published recently. Additional objectives were to compare temperatures for enrichment in Rappaport–Vassiliadis broth (37 vs 42 °C) and to evaluate further delayed secondary enrichment (DSE) with swine faecal samples ( Nietfield et al . 1998 ; O'Carroll et al .…”

Section: Introductionmentioning

confidence: 99%

Comparison of methods for isolating Salmonella bacteria from faeces of naturally infected pigs

et al. 2000

View full text Add to dashboard Cite

A series of experiments was conducted using faecal samples collected from commercial swine farms to evaluate the effects of variation in methods used for the detection of Salmonella bacteria. The primary objective of the studies was to compare the protocols routinely used in two laboratories in the USA. The studies included five experiments comparing the enrichment protocols used routinely in the respective laboratories (Method 1: 10 g faeces—buffered peptone water (BPW) pre‐enrichment—selective enrichment in Rappaport/Vassiliadis (RV) broth; Method 2: ∼1g faeces—primary enrichments in tetrathionate and Hajna GN broths—secondary enrichment in RV broth). The effects of enrichment temperatures (37 vs 42 °C) using RV broth (two experiments) and delayed secondary enrichment (four experiments) were also evaluated. Direct comparison of Method 1 and Method 2 indicated comparable results. However, when compared using faecal samples of equal weight, the Method 2 enrichment protocol was more sensitive for detecting Salmonella bacteria than the Method 1 protocol. Enrichment in RV at 42 °C was superior to 37 °C, particularly for samples that were pre‐enriched in BPW. Delayed secondary enrichment increased detection of Salmonella bacteria in swine faeces. These results highlight the imperfect sensitivity of culture methods, and the need for researchers to consider the sensitivity of bacteriological methods in the design and interpretation of the results of epidemiologic studies based on faecal culture

show abstract

“…Tetrathionate is considered more inhibitory than GN Hajna in that it restricts competing microorganisms from the gastrointestinal tract, and it has been proposed as the enrichment of choice when culturing fecal samples. 5,9,11 It has been suggested that GN Hajna is superior to other primary enrichments for isolation of S. choleraesuis, 1,2,6-8 hence the rationale for evaluating both enrichments in our study. When GN Hajna and tetrathionate were compared as initial enrichments in a previous study, 1 GN Hajna demonstrated a significant advantage over tetrathionate for S. choleraesuis recovery from rectal swabs.…”

mentioning

confidence: 99%

“…1,2,6-8 However, when culturing for salmonellae other than Salmonella Choleraesuis, tetrathionate broth has been routinely utilized for enrichment. 5,9,11 A survey was conducted to determine the prevalence of salmonellae at slaughter in pigs from 5 farms from an integrated swine operation. Because there was no prior history of salmonellae isolations from these farms, there was no predictability for serotypes of salmonellae that might be recovered.…”

mentioning

confidence: 99%

Comparison of GN Hajna and Tetrathionate as Initial Enrichment for Salmonellae Recovery from Swine Lymph Nodes and Cecal Contents Collected at Slaughter

et al. 2001

View full text Add to dashboard Cite

An epidemiologic survey was conducted to determine the prevalence of salmonellae in swine from 5 farms of an integrated swine operation. The purpose of this study was to evaluate the recovery efficiencies for salmonellae from swine lymph nodes and cecal contents when GN Hajna and tetrathionate were compared as initial enrichments. Salmonellae were isolated from 61% of 645 pigs at slaughter; 324 positive cultures were from lymph nodes, and 224 were from cecal contents. Frequently, pigs had salmonellae isolated from both the lymph nodes and cecal contents. Total isolations, regardless of source, were similar for GN Hajna (247) and tetrathionate (301). There was no difference ( P > 0.05) in the number of isolations from lymph nodes when GN Hajna enrichment was compared with tetrathionate enrichment (174 vs. 150). However, there was a significant ( P > 0.05) advantage of utilizing tetrathionate when compared with GN Hajna for isolations from cecal contents (151 vs. 73).

show abstract

Comparison of Conventional and Delayed Secondary Enrichment for Isolation of Salmonella Spp. from Swine Samples

Cited by 16 publications

References 6 publications

Development of an antigen-capture monoclonal antibody–based enzyme-linked immunosorbent assay and comparison with culture for detection ofSalmonella entericaserovar Enteritidis in poultry hatchery environmental samples

Development of an antigen-capture monoclonal antibody–based enzyme-linked immunosorbent assay and comparison with culture for detection ofSalmonella entericaserovar Enteritidis in poultry hatchery environmental samples

Comparison of methods for isolating Salmonella bacteria from faeces of naturally infected pigs

Comparison of GN Hajna and Tetrathionate as Initial Enrichment for Salmonellae Recovery from Swine Lymph Nodes and Cecal Contents Collected at Slaughter

Contact Info

Product

Resources

About