| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 5797814 | The Veterinary Journal | 2014 | 6 Pages |
â¢S.âsuis isolates from Iberian pigs (IP) were molecularly characterised for the first time.â¢IP showed similar S.âsuis carriage rates to those observed in common breed pigs (CBP).â¢S.âsuis carriage rate is not affected by the system (outdoor/indoor) in which IP are bred.â¢Molecular typing data suggest a population of serotype 2 common to IP and CBP.â¢Knowledge of S.âsuis diversity will contribute to understand the population structure of this pathogen.
The Iberian pig (IP) is a traditional Spanish breed variety of the domestic pig (Sus scrofa domesticus) with high economic importance because of the value of the dry-cured products in national and international markets. The genetic characteristics of tonsillar and clinical Streptococcus suis isolates from the IP maintained under extensive or intensive management conditions were investigated. S.âsuis isolates from IP pigs were compared with S.âsuis isolates from intensively-farmed pigs of common breeds (CBP). S.âsuis was isolated from 48.4% of the IP tonsils examined, indicating wide distribution among IP pigs.Serotypes 1 (9.4%), 2 (8.6%) and 9 (7%) were the most commonly found, although a high percentage of S.âsuis isolates were not typeable by coagglutination testing. No significant differences in carrier rates or serotype diversity were observed between management systems, indicating that intensive farming does not influence S.âsuis colonisation. Both pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis showed a serotype-based distribution of S.âsuis IP isolates. Serotypes 1 and 2 S.âsuis isolates were grouped in the same cluster, whereas isolates of serotypes 9 and 7 were assigned to another cluster. All clinical and most tonsillar serotype 2 IP isolates were assigned to sequence type 1 (ST1) and exhibited the virulence genotype mrp+/epf+/sly+, indicating a high distribution of this genetic lineage among IP as well as a population of serotype 2 common to IPs and CBPs. The only clinical isolate of serotype 9 from IP was assigned to ST123, a sequence type associated with clinical isolates in CBPs in Spain.
