Does anyone know about the Mareks Vaccine and how the virus works? It is my understanding that the vaccine protects the bird from getting Mareks symptoms and getting sick, but that a vaccinated bird can still carry the virus and spread it to any non vaccinated birds. We have a mixed flock, some from the farm store and some home hatch. Most any bird bought from a local farm store has been vaccinated.
We are pretty sure we had Mareks run through our flock a couple of years ago. Only the home hatch showed symptoms and died. We did not do a post mortem to confirm that it was Mareks. But the symptoms pointed to it; young healthy birds were quickly paralyzed. They had no diareah, or other symptoms, they were hungry and continued to eat if they could. None of the vaccinated birds got sick we assumed it was Mareks.
Now we keep our home hatch and store bought birds separated (kind of). We do have about 4 rogue home hatch birds that roam the farm, they sleep in a tree and are exposed to all the other birds and their living areas. They are about 4 years old now and were present for the Mareks outbreak. I think they have either survived Mareks, built an immunity, or the Mareks has run its course through our farm and missed them.
I have a fried who breeds and sells pullets. She home vaccinates all her birds. It is simple to do at home, you just have to buy the vaccine and give the day old chicks a shot. The problems is I have only found the vaccine in very large doses and it does not keep.
We have decided to not vaccinate our home hatch and things seem to have smoothed out. We loose a sick chicken from time to time, but never more than one every 6 months or so. We have over 100 birds, so that doesn't seem like that many.