Animal Health at the farm level: PMWS and PRRS

Table of Contents

1. Introduction
   1. Objectives
   2. Learning goals
   3. Teacher page
2. Unit 1: Importance of PRRS and PMWS to the European pig industries
3. Unit 2: PRRS - causes and predisposing factors
   1. Transmission
   2. Predisposing factors
4. Unit 3: PMWS - causes and predisposing factors
   1. Transmission
   2. Predisposing factors
5. Unit 4: Alternative strategies for managing PRRS and PMWS
   1. Biosecurity and farm management
   2. Vaccination
   3. Depopulation and repopulation (De-pop / re-pop)
   4. Other strategies proposed for PRRS control
6. Unit 5: Outlook for the future
7. Unit 6: Conclusions
8. Completion
   1. Comments
   2. Self-assessment
   3. Evaluation
   4. Bibliography and Useful websites
9. Acknowledgments

Unit 5: Outlook for the future

Our knowledge and understanding of the dynamics of PMWS and PRRS have improved significantly since these diseases emerged. However, it is clear that we do not know enough as yet to effectively control these diseases in all situations. Although it is likely that changes in husbandry might have helped the emergence of these diseases. Given the increased world population and the resulting increased demand for pork, it is also clear that getting back to less intensive production systems, or having smaller herds, would be unrealistic.

It might be thought that disease resistance will develop over time, or genetic resistance in the national herd will gradually emerge. However, these suggestions are speculative. On the other hand, we cannot dismiss the possibility that PCV2 will start mutating and in this situation, the present vaccines will no longer be effective.

So, what can we do for the future?

With the current knowledge, increasing biosecurity, improving husbandry and farm hygiene seem to be the starting points to control PMWS and PRRS. This in combination with vaccination programs in the case of PMWS, or herd isolation in the case of PRRS, seems a good basis for controlling these diseases at a regional level. Given that the pig farming industry in most countries operates either as several large integrated businesses or as a close contact network (nucleus herds, multipliers, feed suppliers, veterinarians, etc), control initiatives by a group of farmers or at a regional level should be feasible.

At the individual farm level the situation should be evaluated and assessed for the best possible options by the farmer and a vet. The vet is valuable in assisting with decision making because he/she has up-to-date knowledge of the subtleties of the current strain of the virus and the behaviour of the disease.