“There has been increasing evidence showing how PCV2 damages sow performance. In addition to its affect on offspring, the virus has also been linked with poor reproductive performance and abortions. Recent research also indicates that the impact of PCV2 on naïve gilts can be quite significant,” Dr Brian says.

Research was conducted in France on two groups of gilts – 165 that were not vaccinated against PCV2 and 165 that were vaccinated with Circovac®¹. A number of key measurements demonstrated the benefits of PCV2 vaccination. Return to oestrus was nearly three times as likely among the non-vaccinated gilts compared to the vaccinated ones at 5.1 per cent versus 1.8 per cent.

Abortions were reduced by than half among the vaccinated gilts at 3.6 per cent compared to 7.3 per cent, and the percentage farrowing was nearly 7 per cent higher among vaccinated gilts (90.5 per cent against 83.9 per cent).

Leading authority Professor Hans Nauwynck, of the Faculty of Veterinary Medicine at Ghent University, says: "Be careful with high health status gilts introduced on to commercial farms. With PCV2 negative gilts, I recommend that you vaccinate them – just like you would for parvovirus prevention."

A study conducted by Leeds University for BPEX showed that the most effective form of vaccination for piglets against PCV2 was to vaccinate both sows and piglets (although just vaccinating sows is the most cost-effective method.)² However, Dr Brian points out that sow vaccination has a number of benefits in its own right. He says: “For sows, as well as gilts, PCV2 vaccination has a number of clear economic benefits. Piglets born from vaccinated sows have a higher birthweight and continue to grow quicker resulting in fewer days to slaughter.² Also vaccinated sows have a better reproductive performance. Research carried out in the UK showed that vaccinated sows produced almost one extra piglet per litter.³

“In the light of all the current evidence, vets and producers need to consider a strategy for PCV2 vaccination which takes into account the whole herd including sows and gilts, not just piglets,” says Dr Brian.

¹ Noirrit et al, IPVS 2010 Proceedings of the 21st IPVS Congress, Vancouver, 2010, p436

² Effect of CIRCOVAC® vaccination of sows on their reproductive performance John Hayden, et al 21st IPVS Congress, Vancouver, 2010

³www.bpex.org.uk/R-and-D/Health-Improvment/A comparison of the efficacy of sow versus individual piglet vaccination against PCV2