Vaccination Against Porcine Parvovirus Infection

Abstract

Of 13 gilts 7 were vaccinated twice at an interval of 3 weeks with an inactivated vaccine against porcine parvovirus (PPV) infection, while the 6 nonvaccinated gilts served as controls. Starting after the 1st vaccination the gilts were bred and, after about 40 days of gestation, challenged intravenously with virulent PPV. The vaccinated gilts produced an antibody respons after the 1st and 2nd vaccination compatible with a primary and a secondary immune response, respectively. The nonvaccinated gilts remained low-titered or PPV antibody negative until after challenge. The gilts were killed after about 90 days of gestation, and their litters were examined. All of 53 fetuses from the vaccinated gilts were alive, and infection with PPV could not be demonstrated. Conversely, 50 of 65 fetuses from the non-vaccinated gilts were infected with PPV, and 43 were dead.

In a field study comprising 2 herds, PPV seronegative or lowtitered gilts were vaccinated before mating. There were no obvious signs of reproductive disorders in the 2 herds during the vaccination trials, and the reproductive performance of vaccinated gilts did not differ significantly from that of non-vaccinated gilts.

Sammendrag

Af 13 gylte blev 7 vaccineret 2 gange med 3 ugers mellemrum med en inaktiveret vaccine mod infektion med porcint parvovirus (PPV), medens 6 kontroldyr ikke blev vaccineret. Løbning af gyltene påbegyndtes efter 1. vaccination, og omkring 40. drægtigheds dag blev de podet intravenøst med PPV. De vaccinerede gylte gav et lavt antistofsvar efter 1. vaccination efterfulgt af en udtalt stigning efter 2. vaccination. De ikke-vaccinerede gylte forblev lavtitrede eller negative for PPV antistof til efter podning. Gyltene blev aflivet omkring 90. drægtighedsdag, og fostrene blev undersøgt. Alle 53 fostre fra de 7 vaccinerede gylte var i live og ikke inficeret med PPV. Derimod var 50 af 65 fostre fra de 6 ikke-vaccinerede gylte inficeret med PPV, og 43 var døde.

I 2 besætninger blev PPV seronegative eller lavtitrede gylte vaccineret før løbning. Der var ingen synlige tegn på reproduktionsforstyrrelser i vaccinationsperioden og reproduktionsresultaterne blandt vaccinerede og ikke-vaccinerede gylte fandtes ikke signifikant forskellige.