TDK conference 2015

Porcine parvovirus 1 (PPV1, current name Ungulate tetraparvovirus 1) is one of the pathogens that can cause high economic losses in the swine industry. PPV1 is endemic in populations worldwide. The PPV1 belongs to the Parvoviridae family, it contains a single-stranded DNA genome and a non-enveloped protein capsid. Therefore this virus is highly resistant to most disinfectants, so the eradication of PPV1 in swine farms is a very difficult or impossible task.

The PPV1 infection is usually asymptomatic in swine, most of the losses are manifested in reproductive abnormalities. These reproductive disorders can be either the absorption of embryos, or the birth of a mummified fetus or a living, but weak offspring, depending on the time of the infection of susceptible pregnant gilts or sows. Abortion is a rarely occurring consequence. The PPV1 infection causes severe economic losses, so an appropriate and effective protection against PPV1 is highly important. In order to apply an appropriate control strategy, we must know the antibody profile. There are only few available data about the dynamic of PPV1 specific antibody changes in infected and vaccinated herds, and those are published around the 1980s.

In this study, serum samples (sows, 2-150 days old pigs) from 4 different swine herds were examined to determine the PPV1 specific antibody profile using indirect immunofluorescence method. According to our results, the maternal antibodies are already absent around the 1-2 months of age, and because of the infection caused specific humoral immune response, high PPV1 specific antibody level was detected in some individual of the older age groups. The swine herds, in terms of protection against PPV1, are heterogeneous (which is also true for sows!), which favors the survival and spreading of the virus within the herds. Vaccines against PPV1 are routinely used in most swine herds. Usually the recommended vaccination time is around the age of 6 months. Our results suggest that the modification of PPV1 vaccination protocol could be necessary to establish homogeneous immune status of the animals in order to have a more effective defense.