Dr Andrew Tucker – Charles Street Veterinary Consultancy
What is Parvovirus?
Porcine parvovirus (PPV) is a small DNA virus. It is ubiquitous among pigs throughout the world and is endemic in most herds that have been tested. The virus spreads via oral and nasal secretions, faeces, urine, semen and products of parturition. The disease develops mainly when previously unexposed dams are exposed during the first half of gestation. The foetus or embryo is then infected across the placenta. How do you know if it’s on your farm?
Parvovirus causes returns to oestrus, failure to farrow, decrease in litter size, increased number of mummies, increase number of stillbirths and sometimes abortions. It usually infects the foetus or embryo without showing any outward maternal clinical signs. Infection is particularly prominent in newly introduced animals and first litter gilts.
How do you treat or prevent it?
It is at this stage not possible to eradicate parvovirus from your herd. Being a virus it is not possible to treat the infection so in this case prevention is certainly better then cure. Vaccination is widely used to prevent parvovirus. A typical vaccine is inactivated and is administered as two doses, 3-4 weeks apart with follow up vaccinations every 6 months.
The virus can also be transmitted in semen so it is important to vaccinate boars as well. Note that maternal immunity may not disappear until 6-7 months of age so it is important to adapt the gilt vaccination programme so as not to vaccinate before this time.
References:
Pig Diseases – D.J.Taylor; Diseases of Swine – Straw, Zimmerman, D’Allaire, Taylor