There are four pillars of PRRS control. You must apply all four in order to successfully control PRRS.
In this blog we discuss how vaccination can be used to control or even eliminate PRRS.
The PRRS virus can only multiply in a pig (it can’t spread to other animals or humans), and it is very poor at surviving in the environment e.g. outside of the pig the virus will ‘die’ quite quickly. Essentially the PRRS virus needs a susceptible, non-immune pig in order to survive, multiply and spread. So if all of the pigs in the herd are immune at the same time, then the PRRS virus has nowhere to live or replicate and it could be entirely eliminated.
There are lots of vaccination protocols from which you and your vet might choose:
1. Breeding Herd Only:
- Mass vaccination: Vaccinate all breeding stock at the same time (normally every quarter)
- “6-60”: Vaccination 6 days after farrowing and 60 days post service
2. Breeding Herd and Piglet Vaccination
The breeding herd, in theory, is the source of virus for piglets. Therefore if you can control PRRS in the breeding herd with vaccination, then it should also control the PRRS circulation in the feeding herd. However there are several situations which compromise this theory:
- Farrow to Finish on same site: PRRS circulation in the finishing herd can spread back to the breeding herd and younger age groups.
- Weaning off-site:
- If the breeding herd remains unstable some litters will be PRRS positive at weaning and will spread the virus to non-litter mates.
- If sources are mixed.
- A site of poor biosecurity e.g. places likely to become infected with PRRS, for example places with very close PRRS positive neighbours.
Remember, just one PRRS positive piglet entering a finishing site could spread the virus across the entire unit, if the other piglets have no immunity it will create significant damage to health, mortality, growth and productivity. A recent study demonstrated that a mild outbreak of PRRS on a finishing unit costs €3.77 per pig (around £3.30). So any live PRRS vaccine used should have significant return on investment in unstable PRRS infected herds. Suvaxyn® PRRS MLV is the recently launched PRRS vaccine from Zoetis. It can be used in piglets, gilts and sows, and can be administered from just one day of age! This provides extra convenience as it can be given during piglet processing in the first week of life and it gives the earliest protection possible to the piglet, which can be in place by the critical risk period after weaning. Discuss your choice of PRRS vaccine and vaccination protocol with your veterinary surgeon.
Suvaxyn® PRRS MLV contains modified live porcine reproductive and respiratory syndrome (PRRS) virus, strain 96V198. For the active immunisation of clinically healthy pigs from 1 day of age in a PRRS virus contaminated environment, to reduce viraemia and nasal shedding caused by infection with European strains of PRRS virus (genotype 1). POM-V For information about side effects, precautions, warnings and contra-indications, please refer to the product packaging and package leaflet.
For further information please contact Zoetis UK Limited, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. www.zoetis.co.uk Customer Support: 0845 300 8034. Use medicines responsibly (www.noah.co.uk/responsible). Date of preparation: February 2018. AH101/18