Mereks Disease in Back Yard Chicken

[wendybrasfield]

Our year old hen was put to sleep. We still have 4 hens (14 months old) and 11 chicks (2 1/2 months old). City vet said 80% chance they will be infected and die. Does anyone have experience with this disease? We got the hens for eggs, small scale. Its been a year since we got the hens from a friend that have a ranch. None were vacinated as being new to this, I did not realize this was needed. Plus we were given 11 chicks off a ranch that were just hatched and now these gals and guys are 2 1/2 months. All are still living, they have the entire yard to play and sleep in hutch separate from hens. How doomed are we to suffer total loss? They are more than chickens, they are our pets.

 

[cicene mete]

It really depends on the strain of the disease. Most chickens will be exposed to Marek's at some point during their lifetimes. This is why it is usually much more lethal for younger chickens than for older chickens, who have presumably developed some resistance. We had a one-year-old survive the disease, and we have lost two juveniles. Often times, chickens will be carriers of the disease and will show no symptoms. Sometimes, under periods of stress or other illness the disease will no longer be dormant.

I would not assume that your chickens are going to either a.develop symptoms or b.die even if they get it. If the bird is older and has some weight reserves, you can sometimes nurse them through the paralysis period.

There are basically two ways of dealing with the disease: 1. Vaccinate. This does not keep the birds from getting the disease, but rather it keeps them from developing symptoms and dying. Note that they can still be carriers even if they've been vaccinated.

2. Breed for resistance. This would involve keeping a survivor and culling or not breeding any birds that develop symptoms. Over time, you can breed a resistant flock.

 

[cicene mete]

Just something to watch for, many chickens develop symptoms at around 20 weeks, the period when they come in to lay. It's a stressful time on the body.

At some point, all you can do is practice good bio security, quarantine any new arrivals to the flock, and accept that you can only do so much. Not that it makes it any easier; it is devastating to lose a pet chicken. However, I would decide whether you want to breed for resistance, and if not, I would vaccinate any new chicks.

 

[wendybrasfield]

Thanks everyone for your input.
We got some hens for "eggs only" about 14 months ago - not to breed. Just wanted to have eggs and company in the yard. Of course they grew on us and have become a pet. One of the hens from this group was the one that got mereks and we put her to sleep - it was her leg. Vet was certain this was disease and no other tests were done.
Although she was out that day having a dirt bath and eating well, the vet said watching her progress thru the disease is hard so thats when I put her down. I know the three other hens in her circle knew she was hurt because one would always stay with her.
The chicks came around by chance (helping save them from death at the stable from dogs). Never intended to keep them as we found homes for them already - just waiting for them to grow some. Our city does not allow roosters. Vet said too late to vacinate - they have to be a day old.
So here I am with 11 chicks and a few hens left.
I certainly agree that if we introduce anymore to group, they will be vacinated!
Any more thoughts you have, I'd appreciate. Thanks everyone - I feel somewhat better. What happens, happens. I just don't want to end their lives without the disease present.

 

[silkiechick05]

Yes, i heard that you can't vaccinate if you don't do it when they are first hatched (one day old)


Is that true?

Mine aren't vaccinated, and i would like to prevent the disease, if possible.

 

[cicene mete]

You can vaccinate at any age, but the earlier the better. One day old is ideal. There is some evidence to suggest that later vaccination offers some benefit, but in general, the idea is that if you wait for very long, they will probably already have been exposed to the disease.

Here is an article about Marek's disease and later vaccination: http://www.firststatevetsupply.com/poultry-health/mareks-disease.html

 

[ArizonaDesertChicks]

Quote:
You said your chicken was dustbathing & eating well the day you took her to the vet and had her put down. What were her symptoms? Was she limping? If so, when did she start? I'm surprised that your vet diagnosed Marek's without doing any tests. I've heard it can't be diagnosed without tests - there are other reasons a hen can go lame or have paralysis besides Marek's disease. Also, saying that your flock has an 80% chance of getting the disease & dying also seems pretty high to me.

14 months is kind of late to be coming down with Marek's. According to this article:
http://www.dpiw.tas.gov.au/inter.nsf/WebPages/CART-6PTVYH?open
"Young birds are most susceptible to infection. Most deaths from Marek’s disease occur between 8 and 20 weeks of age, although in some cases the disease may be seen in birds as young as 3-4 weeks of age or as old as one year of age."

I don't think you can be 100% sure that your hen had Marek's since there was no necropsy or internal testing done, but even if she did I think your other 14 month old chickens should be fine since they're old enough to have built up immunity. You'll have to wait and see on the little ones.

To protect the little ones. Try to keep them from getting stressed.
I would not try to integrate your 11 week old chicks into the older hens' pen until the chicks are the same size - 5-6 months (because of the possiblity of Marek's, the longer you can hold off, the better) and the younger ones should not be outnumbered by the older ones (if possible). Putting flocks together is very stressful on the younger birds (older flocks are terrible bullies) and your chicks will not be past the danger zone until they are at least 5-6 months old.

 

[beckt]

I was told by my vet the only way to test for Mereks is to have the necropsy done. and even then its not 100% to know for sure. Like stated above there are other things that can make a hen limp. If you have anymore go down please have a necropsy done to learn more. Your vet should be able to tell you the closest place to have this done.