vaccination or not, risks of contamination

[Robert Jan]

We want to start keeping chickens again that will run free.
We are about to laying eggs in our incubator and I am not sure when it comes to vaccinating the baby chicks along with the fact if other chickens have had a vaccination or not.
The question arises whether we vaccinate the chicks against Mareks as soon as they hatch (If this is even possible due to the fact not many vets have the vaccine or it is sold per 1000 vaccines).

As I have understand it, it comes down to this:
Mareks is always present but does not always have to lead to symptoms, if it does, chickens will die. It is only possible to vaccinate baby chicks on their first day when coming out of the incubator.
Chickens that have been vaccinated are now carrying Mareks and can therefore infect ungrafted chickens. This comes down to a choise you should make, whether you vaccinate everything or nothing at all and also when adding mature chickens OR baby chicks, you only add grafted or respectively ungrafted chickens. Exceptions are when the bloodline is resistant to Mareks and they possibly can carry the disease but it will never come to an outbreak.
Same case is if you have grafted chickens which are likely to carry Mareks (due to their vaccine), they do not have to infect new chickens or hatched chicks if these are resistent from there blood line. Of course they will become carriers too. If there is introduced a chicken which is not resistant or has not had a vaccine, then most likely it will be infected and will die.
Some breeds are more vulnerable to Mareks than others and some have a strong resistant blood line, but you honestly never know for sure.

I am not a big fan of grafting my animals from protection purposes but I am wondering if above info is correct or not.
The case is that I have been offered 2 beautiful 1 year old chickens that have been vaccinated against Mareks. When I let these 2 wonder free around the property and after on add the grown (ungrafted) incubated chicks, I am afraid I will expose these incubated chicks to a high risk because the 2 chickens are likely being carriers of Mareks because of the vaccin.
The same problem arises when you later on want to add baby chicks or grown chickens of which you are not sure they have been grafted or worse, you don’t know it they are carriers. Grown chickens which are not grafted can carry Mareks as they can be resistant from there bloodline, but can therefore infect others.

I would like to know what choices you should make, also regarding the later addition of already born chicks or adult animals.
What do you all do?

If something in my story is not correct, I would of course like to hear it!

 

[sloanbychoice]

Most of that sounds correct. The clarification though... getting the vaccine doesn’t make them carriers automatically or cause them to infect unvaccinated birds, it means that IF they contract it, then they will asymptomatically carry and infect.
There are some very vehement opinions on Mareks vaccine. I don’t get involved in those debates. It’s over my head.
I know that mine aren’t vaxed, and I don’t go out of my way to vax them for it. Personally, if I had hatchlings, I wouldn’t bother, because like you said, you have to buy tons of it.

 

[humblehillsfarm]

I made the decision not to vaccinate two baby chicks that my hen hatched even though the rest of the flock is vaccinated. The risk is there in that decision, but I wasn't comfortable doing the vaccine myself nor did I want to buy a large vial for two chicks.

 

[Robert Jan]

As I have been told, by vaccinating chickens agains Marek they will get a live vaccine (most vaccines are, I know) but this live Marek variation will cause 99% of the grafted chickens to become carriers. And therefore they will become a huge risk to ungrafted chickens and baby chicks unless those are resistant from there blood line but this you, have to find out the hard way..

Most of that sounds correct. The clarification though... getting the vaccine doesn’t make them carriers automatically or cause them to infect unvaccinated birds, it means that IF they contract it, then they will asymptomatically carry and infect.
There are some very vehement opinions on Mareks vaccine. I don’t get involved in those debates. It’s over my head.
I know that mine aren’t vaxed, and I don’t go out of my way to vax them for it. Personally, if I had hatchlings, I wouldn’t bother, because like you said, you have to buy tons of it.

Reading this is a bit of a relief as this would mean I have been misinformed about the things I have written above the quote.
So, grafted chickens will only become carriers of Marek if they contact infected chickens or carriers of Marek. But due to their vaccine they will not get the symptoms but are able to infect ungrafted chickens. If those ungrafted chickens are resistant by blood line they will become carriers also.

Case is, either way, it is a gamble to add self hatched chicks to you flock which has not been raised for zero by yourself. They might have nothing or the might be carriers while not getting sick due to either their vaccine or resistant blood line. Same applies to adding grafted or ungrafted mature chickens to your flock.

Sounds right?
If so this is a huge gamble every time you want to add chickens...

 

[sloanbychoice]

I’m pretty sure I read that the vaccine comes from a different strain, something to do with turkeys...?
So because of that, they’re not just going to give it to another chicken, but if they contract it, they will.

It is a gamble, but it’s one that lots of people take.
I know it comes from outside sources, so I’m a little overly cautious with my flock.

I won’t allow other chicken owners into my runs.
I don’t wear the same boots into my run that I wear when I’m out and about.
I have netting all around the run so wild birds can’t get in.

I figure I do the best I can and hope for the best.

 

[Robert Jan]

I’m pretty sure I read that the vaccine comes from a different strain, something to do with turkeys...?

ah ok, didn’t know that. What exactly do ypu mean with:

So because of that, they’re not just going to give it to another chicken, but if they contract it, they will.

do you mean grafted chickens will give it to other chickens after the grafted chickens have contacted infected chickens?

you are right a bout the pro cautious like changing boots!

 

[sloanbychoice]

Yes. Even vaccinated, they still have to contract it somewhere first, before being contagious.
It’s considered a “leaky” vaccine. It’s not like the MMR vaccine in people, where, once vaccinated, you’re immune.
It, instead, let’s the birds catch the disease, but keeps them from having the symptoms and killing them. That’s what makes them carriers. Once they catch it, you don’t know. Then they can be harmful to birds who are not vaccinated.

 

[LadiesAndJane]

My understanding is your chickens can also get it from wild birds and wild chickens. We have lots of those where I live! I plan on vaccinating all my baby chicks when they hatch