Affiliation:
1. Division of Infectious Diseases and Food Chain Quality, Institute for Animal Science and Health, 8200 AB Lelystad, The Netherlands
Abstract
ABSTRACT
Multiplex PCR assays for the detection and identification of various
Streptococcus suis
strains in tonsillar specimens from pigs were developed and evaluated. In two separate reactions, five distinct DNA targets were amplified. Three targets, based on the
S. suis
capsular polysaccharide (
cps
) genes specific for serotypes 1 (and 14), 7, and 9, were amplified in multiplex PCR I. Two other targets, based on the serotype 2- (and 1/2-) specific
cps
gene and the
epf
gene, encoding the EF proteins of virulent serotype 2 and highly virulent serotype 1 strains, were amplified in multiplex PCR II. To identify false-negative results, firefly luciferase (
luc
) DNA and primers based on the
luc
gene were included in the assay. The multiplex PCR assays were evaluated with tonsillar specimens from pigs infected with
S. suis
strains. The results obtained with the PCR assays were compared with the results obtained with a bacteriological examination. Most (94%) of the results obtained with multiplex PCR assays were confirmed by the bacteriological examination. The PCR method seems to be more sensitive compared to the bacteriological method, since the remaining 6% of the samples were positive by PCR and negative by bacteriological examination. These results indicate that the PCR method is highly specific for the detection of
S. suis
strains most frequently involved in clinical disease in infected pig herds. The serotypes found by PCR in tonsillar specimens from diseased pigs were compared with the serotypes of the strains isolated from the affected tissues of the same pigs. The results showed that there is significant association between carriership and clinical illness for
S. suis
serotype 9 and EF-positive serotype 2 strains and not for serotype 7 and EF-negative serotype 2 (or 1/2) strains.
Publisher
American Society for Microbiology
Reference29 articles.
1. Relatedness of
Streptococcus suis
Isolates of Various Serotypes and Clinical Backgrounds as Evaluated by Macrorestriction Analysis and Expression of Potential Virulence Traits
2. Carrier rate of Streptococcus suis capsular type 2 in palatine tonsils of slaughtered pigs
3. Chengappa, M. M., L. W. Pace, J. A. Williams, C. H. Herren, and S. E. Ascher. 1990. Efficacy of tiamulin against experimentally induced Streptococcus suis type-2 infection in swine. J. Am. Vet. Med. Assoc.197:1467-1470.
4. Devriese, L. A., K. Ceyssens, J. Hommez, R. Kilpper Balz, and K. H. Schleifer. 1991. Characteristics of different Streptococcus suis ecovars and description of a simplified identification method. Vet. Microbiol.26:141-150.
5. Characterization of six new capsular types (23 through 28) of Streptococcus suis
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