It can affect them whether or not they have the vaccine.
The leg paralysis sounds like Marek's. I would cull as this is a long and excruitiang death. I had one with leg paralysis and when I had a necropsy done she had numerous internal tumors which are very painful. I know that is difficult but at this point there is nothing you can do.
Marek's will be active in your flock. You do not need to cull the entire flock however because it is very common. Its spread by dander from the feathers, so it is EXTREMELY hard to completely get rid of. Most birds have it just never show any signs. Its not spread vertically ( by egg). I would quarantine your flock for 30 days. No new birds. And don't do anything to stress your flock out.
I had 2 affected and lost an additional 2. I culled them immediatly once I saw the leg paralysis, as I had it diagnosed by necropsy.
No one has shown any signs or symptoms since, and that was 8 months ago, I have since added birds to my flock with no consequences.
I would be careful adding any new chicks or young birds after this. Wait atleast 5 months and at that point they are less likley to have it affect them and have a decent immune system, if they have been vaccinated then by 5 months the vaccine has usually done its job as the vaccine needs time to build up in the system ( but remember vaccinated birds still have a chance to get mareks anyways)
Leukosis has similar symptoms, which is far worse then Marek's. You may want to consider a necropsy by a local vet.
There are some really good threads on here about Mareks, I would look into those.
thanks for the reply and words of hope for the rest of the flock. I had read the other threads on Mareks and my heart sank when the symptoms all fit. I guess i now know what i need to do to end her suffering. I will look into getting a necropsy done.
Wait! Marek's usually strikes chickens at 2-5 months old. I had a pullet who appeared to have Marek's last fall. I put her inside the house in a rabbit cage, fashioned a sling from an old shirt(cut holes for her legs and made sure not to cover her cloaca) and let her hang there for 2 months. I took her down for a bit every day, and she always had a good appetite and she one day seemed to have a bit of coordination in her legs. So she went outside into a cage where she gained her strength back for a couple more weeks, enough to be with the rest of the flock. Today you would never know she had a problem with her legs. She's even laying eggs now. There were a couple of times when she got malpositioned in the sling and she got stressed out causing her poop to change to diarrhea, or also if I left her out of the sling for a day or so that would stress her out. So I kept her in the sling most of the time with food and water within pecking distance, and happily she did recover. I tried giving her St. John's wort as recommended by some people, but after about a week of that, I got lazy and stopped. She hated it, too.
I had a hen with mareks symptoms last fall. I just made sure the others left her alone and that she was able to get to the food and water. Now you would never be able to tell there was ever a problem. No other birds have had any symptoms.
this hen is about 3 or 4 years old. We bought the property in Aug. 09 so not sure her exact age. she is not eating/drinking on her own at all. Very prominent breast bone. I have been force feeding her a mixture of scrambled egg, oatmeal, yogurt, a little applesauce, and some honey for energy. Have been mixing her crumbles in it also. Have tried powdered antibiotics, electrolytes/vitamins, and small amount of cod liver oil. Heat lamp in the eve. If it wasn't for the force feeding, i think she would already be gone. She doesn't act like in pain, just stays laying in her box, and if you force her to move, she only uses one leg and falls over flapping. No exposure to baby chicks or pullets. talked to state of calif. ag and they will do a free necropsy if i fed ex with ice to Davis. Hate to cull her if it is something else, but not looking good.
She is a little old for Marek's, but it is possible that she has been exposed earlier in life and has just been a carrier. You can kepp trying to treat her, you never know, as long as she doesn't appear to be in pain. I treated one for 3 weeks before she gave up. The necropsy did say probably Marek's, but none of my other birds have gotten sick and has been over a month.
You must be in CA, as am I. You could ask your vet if they will ship the bird via carrier for you. Mine did that for me. I think it was about 25.00. Maybe a little more than FedEx, but certainly easier, and it gets there overnight.
Good luck, and I am sorry that you are having to go through this.
It may be Marek's if all the symptoms fit.
One of my RIR's had paralysis of one leg, it got worse and worse, splayed out wings for balance, and she couldn't move around the brooder at about 6 weeks or so. Some local chicken experts told me it was probably Marek's and to cull her and maybe the whole flock. I did not follow their advice, but did speak with another person I respect. He made some suggestions regarding medication (tetracycline? I think it was) and vitamins and electrolytes. That was about 10 months ago. She healed well, walks fine (I really can't tell you which one it was) and is a great egg-layer. Listen to opinions, and then do what your inner wisdom tells you is right.
went and bought the blue gel ice packs today that the calif. agri. requires for shipping and am freezing them tonight. Will cull tomorrow if Davis will take a Saturday delivery. She doesn't seem in pain, but its so pitiful to see her flop over and she won't touch food or water at all. I have to face that she is just not getting any better. Am wondering if she is now blind-I can bring my finger right up to her eye without her flinching or blinking-just stares straight ahead. Another chicken now has the green diarrhea. I just pray that my little black silkie who is such a clown, my speckles barred rock, and my giant white bantam don't get this!