Spanish Study Aims to Improve PMWS Diagnosis
A targeted sampling approach did not give better estimates than random sampling for the diagnosis of post-weaning multisystemic wasting syndrome (PMWS), according to recently published research from Spain.Cortey and colleagues at the Autonomous University of Barcelona compared theoretical and experimental approaches to estimate the usefulness of pooled serum samples for the diagnosis of PMWS. Their paper was published in the March issue of Journal of Veterinary Diagnostic Investigation.
According to Cortey and co-authors, classical PMWS diagnosis is based on postmortem finding, i.e. histopathology plus viral detection in lymphoid tissues). Because one of the major differences between PMWS-affected and non-affected pigs is porcine circovirus-2 (PCV-2) load in serum and tissues, real-time quantitative polymerase chain reaction (qPCR) has been suggested as a potential diagnostic technique for the disease.
The objective of the Barcelona study was to assess the applicability of qPCR to quantify PCV-2 loads in pooled serum samples as an easy-to-use PMWS diagnostic tool at the herd level.
The experimental design included two simulation studies with several serum pool sizes from pigs already screened for PMWS by histopathology and detection of PCV-2 by qPCR. Several qPCR thresholds were defined and validated with experimental pools created in the laboratory.
Th eresearchers found that quantitative PCR on pooled serum samples did not result in a sufficiently reliable alternative method to the classical PMWS diagnosis method based on individual clinical, histopathological and PCV-2 detection criteria.
However, serum pools seemed to be an alternative at a low economic cost for the quantification of PCV-2 loads in suspicious herds, concluded Cortey and co-authors. They added that a targeted sampling approach – which included only clinically diseased animals – gave no better estimates than random sampling.
Reference
Cortey, M., S. Napp, A. Alba, E. Pileri, L. Grau-Roma, M. Sibila and J. Segalés. 2011. Theoretical and experimental approaches to estimate the usefulness of pooled serum samples for the diagnosis of postweaning multisystemic wasting syndrome. Journal of Veterinary Diagnostic Investigation, 23 (2): 233-240. doi: 10.1177/104063871102300206
Further Reading
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Further Reading
- | Find out more information on Post-Weaning Multisystemic Wasting Syndrome (PMWS) by clicking here. |
July 2011