Key Messages

A retrospective study (2003-2005) analyzed blood samples from 1695 sow farms and 1613 fattening farms from Spain to detect PRRSV seropositive samples.

In 2005 PRRSV antibodies were detected in 85 per cent of the sow herds and 83 per cent of the fattening herds.

Also, 44 farms from high-density areas in which no vaccine was used were surveyed and tested and the percentage of positive herds was even higher (91 per cent and 86 per cent).

Article Brief

A retrospective study was carried out in Spain with blood samples submitted in 2003, 2004 and 2005 from sow farms, fattening and boar herds. Several pathogens were screened (PRRSV, SIV, ADV PPV and PCV2).

For the years 2003, 2004 and 2005, there were samples from 604, 519 and 572 sow herds and also sample from 541, 507 and 565 fattening farms, respectively, available to perform the PRRSV analyses.

High seroprevalences were observed for PRRSV in sow and fattening pig herds, the sow farm prevalence for PRRS was between 85 and 89 per cent and for fattening farms, it was between 78 per cent and 83 per cent.

In order to eliminate some of the bias due to the fact that the samples were sent for routine analyses, not for the purpose of this study, 66 farms were surveyed and sampled. 44 of these farms were not vaccinated and still the seroprevalence of positive PRRS farms was 91 per cent for sows and 86 per cent for pigs.

These 44 farms were also surveyed for some production parameters (litters per sow per year, live born (LB piglets), total weaned per sow per year, nursery and fattening mortality), however no statistical differences were found due to the different PRRS status. However, the authors do not rule out the possibility of an effect of any of the studied variables since a low number of farms was studied.

Reference

Lopez-Soria S., Maldonado J., Riera P., Nofrarias M., Espinal A., Valero O., Blanchard P., Jestin A., Casal J., Domingo M., Artigas C. and Segales J. 2010. Selected swine viral pathogens in indoor pigs in Spain: Seroprevalence and farm-level characteristics. Transbound. Emerg. Dis. 2010 Jun;57(3):171-179.

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