One of the biggest risks of getting PRRS on your farm is through the purchase of new gilts. The advice is therefore quite obvious: raise your own gilts. That is easy to say now, but in practice it is not always feasible. Many companies still purchase their gilts to this day.
“Then it is good to be aware of the high risk involved and therefore draw up a strict quarantine and adaptation plan,” says Karen Van Neste, veterinarian at MSD Animal Health. “How long that period should last depends on the company, but the ideal is 12 weeks. A good adaptation period can be divided into a number of phases. It is of course important that the new animals are kept separate during the entire quarantine period, preferably in a house that is completely separate from the sow house. The PRRS virus can also spread through the air.
Observation phase
The first phase is the observation period. During the first phase, the animals must not come into contact with the germs present on the farm in any way. So consistently do your work first in the quarantine pen before you return to the sow pen with clean clothes, of course. As far as Karen is concerned, the observation phase should last long enough. A period of 6 weeks is not an unnecessary luxury. Animals that suffer from stress are more susceptible to diseases and excrete germs more quickly. Transport, a new environment, these are all stress factors. The observation phase is also intended to receive signals of disease introduction, not only but also to allow animals to get used to the new environment. Different germs are present on each farm, so it is preferable to buy your animals from the same farm of origin each time. It is important to ensure that the health status of your own animals is at least as high as that of your own animals when registering a fixed provenance company. Vaccinate the gilts as early as possible in the quarantine and if necessary repeat this again shortly before introduction into the sow house.
Build immunity
Vaccination obviously plays an important role in building up immunity against PRRS. If everything goes well during the observation period, and there are no symptoms that indicate the introduction of diseases, vaccination can be started. Vaccination is of course very important in tackling PRRS. This allows gilts to build up immunity before they come into contact with the sow herd.
The next phase is the adaptation phase. This is intended to consciously bring the animals into contact with the germs present on their own farm. This can be done, for example, by entering the barn with clothing that you have also been in the sow barn with or by hanging jute bags that have been hanging in the farrowing barn before. It is of course important that the bags have hung in a stable group.
Cooldownfase
The adaptation phase then gradually transitions into the cool-down phase, which ideally lasts about 4 weeks. You want to prevent problem diseases from persisting on your farm. During this phase, immunity is further built up. This is essential because only when sufficient immunity is present will the gilts be able to withstand the pathogens present in the sows. But don’t forget that germs were actively exposed to the gilts during the adaptation. Of course, it takes time to overcome the induced infections and thereby reduce the excretion of germs again. If not, you will see that the gilts excrete a lot in the sow herd and this can cause instability, which can result in major problems. “A PCR test before introduction has added value, says Karen. To ensure that the gilts do not introduce PRRS into the sow herd, the virus can be searched for and a PCR test performed. If it is positive for a PRRS field virus, the quarantine period may be extended until the PCR test is negative. This will keep your sows’ PRRS status stable.
Karen explains all these tips about quarantine and adaptation in a practical way this video. Did you know that there are several vlogs available that can help you with your PRRS approach? Check them out here.