A field evaluation of mortality rate and growth performance in pigs vaccinated against porcine circovirus type 2.
OBJECTIVE
To evaluate, under field conditions, the effects of a commercial porcine circovirus type 2 (PCV2) vaccine on mortality rate and growth performance in a herd infected with PCV2 that had a history of porcine circovirus disease.


METHODS
Randomized controlled clinical trial.


METHODS
485 commercial, cross-bred, growing pigs.


METHODS
Prior to weaning, pigs were randomly assigned within litter to a vaccination or unvaccinated control group. Pigs in the vaccination group were given a commercial PCV2 vaccine at weaning and 3 weeks later. Mortality rate was recorded, and pigs were weighed prior to vaccination, when moved from the nursery, and prior to marketing. Infection status was assessed by serologic testing and detection of viral DNA in serum.


RESULTS
Compared with control pigs, pigs vaccinated against PCV2 had a significantly lower mortality rate during the finishing phase, significantly higher average daily gain during the finishing phase, and significantly lower likelihood of being lightweight at the time of marketing. For vaccinated pigs, overall mortality rate was reduced by 50% and average daily gain during the finishing period was increased by 9.3%. At the time of marketing, vaccinated pigs weighed an average of 8.8 kg (19.4 lb) more than control pigs, without any difference in days to marketing. Serum PCV2 antibody titers increased in control pigs, and PCV2 DNA was detected, indicating active PCV2 infection.


CONCLUSIONS
Results suggested that vaccination against PCV2 was effective at reducing mortality rate and improving growth performance among pigs in a herd infected with PCV2.
Horlen
Kyle P
KP
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
Dritz
Steve S
SS
Nietfeld
Jerome C
JC
Henry
Steven C
SC
Hesse
Richard A
RA
Oberst
Richard
R
Hays
Michael
M
Anderson
Joseph
J
Rowland
Raymond R R
RR
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D018173:Circoviridae Infections / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D017925:Circovirus / Q000276:immunology*; D005260:Female; D008297:Male; D013552:Swine / Q000254:growth & development*; D013553:Swine Diseases / Q000401:mortality* / Q000517:prevention & control*; D014611:Vaccination / Q000662:veterinary; D014765:Viral Vaccines / Q000276:immunology*; D014886:Weaning; D015430:Weight Gain
D000914:Antibodies, Viral; D014765:Viral Vaccines