Greetings Donna,
Oh, I am so sorry you lost your girl.
As I understand it, it's best to vaccinate chicks at one day old. I don't vaccinate my chicks, but I give injections often enough. You can do it yourself, all you need to do is purchase the vaccine, diluent, syringes and alcohol wipes if you use them. I always wipe the injection site, with an alcohol wipe, first. I would check the local farm/feed store to see if they sell the vaccine.
Here is a link to a video you can watch. Maybe you'll decide to do it with a helper.
www.youtube.com/watch?v=BLyD79Q-dXM
But, if you can't do it yourself, you can call a local vet to administer the vaccinations. The video covers that option too. Depending on where you live, there may be a state or county agriculture or extension department that can also assist you, or at least advise you.
I hope you will have the body of your hen out for a necropsy. Then, you can be certain what she died from. Here again, a vet can do the necropsy, or a state or county agriculture lab or extension office. Freeze her body till you can take it for the necropsy.
I hope I have been helpful. Hopefully, other members with experience in Marek's disease may also advise.
God Bless and peace to you Donna.
Oh, I am so sorry you lost your girl.

As I understand it, it's best to vaccinate chicks at one day old. I don't vaccinate my chicks, but I give injections often enough. You can do it yourself, all you need to do is purchase the vaccine, diluent, syringes and alcohol wipes if you use them. I always wipe the injection site, with an alcohol wipe, first. I would check the local farm/feed store to see if they sell the vaccine.
Here is a link to a video you can watch. Maybe you'll decide to do it with a helper.
www.youtube.com/watch?v=BLyD79Q-dXM
But, if you can't do it yourself, you can call a local vet to administer the vaccinations. The video covers that option too. Depending on where you live, there may be a state or county agriculture or extension department that can also assist you, or at least advise you.
I hope you will have the body of your hen out for a necropsy. Then, you can be certain what she died from. Here again, a vet can do the necropsy, or a state or county agriculture lab or extension office. Freeze her body till you can take it for the necropsy.
I hope I have been helpful. Hopefully, other members with experience in Marek's disease may also advise.
God Bless and peace to you Donna.