Porcine circovirus type 2 infection before and during an outbreak of postweaning multisystemic wasting syndrome on a pig farm in the UK.
The presence of porcine circovirus type 2 (PCV-2) and other pathogens before and during an outbreak of postweaning multisystemic wasting syndrome (PWMS) in pigs is evaluated in this study. At the time of the outbreak on a large commercial pig farm in the UK, serum samples and data were collected in two independent on-going research projects, one in weaned pigs and the other in sows. Serum samples of growing pigs and sows were PCV-2-antibody and PCR positive before and during the PMWS outbreak. Upon sequencing, PCV-2 isolates collected before the outbreak were identified as PCV-2a, and isolates collected during the outbreak were identified as PCV-2b, suggesting a shift of PCV-2 genotypes present on the farm. Pigs in the weaner study were from sows originating from different breeders and an association of sow origin and PCV-2 serostatus in offspring was found. Further, pigs had higher odds to be PCV-2 antigen positive if the sow was PCV-2 antibody positive around farrowing, the sow was of higher parity, and were less likely to test antigen positive if the sow was sourced from a particular breeder. The findings of this study highlight the potential role of the immune status of the sow on the occurrence of PMWS.
Epidemiology and Veterinary Public Health, Royal Veterinary College, London, UK. bwieland@rvc.ac.uk
B
B
Wieland
D
D
Werling
A
A
Nevel
A
A
Rycroft
T G
TG
Demmers
C M
CM
Wathes
S
S
Grierson
A J C
AJ
Cook
S H
SH
Done
D
D
Armstrong
C M
CM
Wathes
D000818:Animals; D000831:Animals, Newborn; D000914:Antibodies, Viral / Q000097:blood*; D017925:Circovirus / Q000145:classification / Q000276:immunology*; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D005838:Genotype; D008297:Male; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000453:epidemiology* / Q000821:virology; D016036:Seroepidemiologic Studies; D013552:Swine; D006113:United Kingdom / Q000453:epidemiology
D000914:Antibodies, Viral