Probably Marek's... we're nearly desperate.

[Flock Leader]

We have a mixed flock of some 5-months-old Israeli chickens, 4-months-old mixed Rhode Island/Sussex, a mixed (probably cochin/silkie) roo who's about 1 year old, and some ex-battery white Leghorn hens who should be about 18 months old.

Around a month ago, a RIR/Sussex cockerel showed a limp. We thought at first it was an injury, but when the cockerel showed signs of rapid paralysis, wasting away and death in a few days, we realized it must be some sort of disease. Then, about 2 weeks ago, the same symptoms were seen in one of our Israeli pullets: limping, then almost complete paralysis in one leg. She's still fighting though, hopping around on one leg, eating and drinking just about the same as always.

Then a few days ago another 4-month-old cockerel started limping, and we are getting desperate. After reading obsessively about every chicken disease out there, I have the evil foreboding it's probably Marek's, because of the neurological symptoms and age of birds. Or could it be something else? We're not going to do a necropsy, don't want to risk being told we must dispose of all our chickens.

We didn't vaccinate our flock. We had the foolish optimistic assumption, when we started out, that providing food, clean water, safe shelter and ample free-range should be enough to keep a relatively low death rate. We didn't expect an epidemic. In the local villages no one vaccinates their birds, and they have been keeping poultry for many centuries, so how come are we so affected?! Vaccinations in general are, historically, a new practice, so how did the species even survive for so long? I had especially high hopes for the local breed to be more hardy, but one of them is affected as I said, and of course if it's Marek's all my birds are carriers.

Right now I'm honestly at a loss of what to do. Vaccinating small flocks isn't cost-effective around here, and it's just heartbreaking to see them all get sick and die one by one, so I've even talked to my husband about opting out of keeping chickens altogether, although it would be a horrible disappointment for us and the kids, we do love our chooks so much. For now we maintan a "none in, none out" policy.

I think I've read half the Marek's threads on the forum and they are all heartbreaking. What should I do?

 

[CMV]

You can send a bird in for necropsy to establish a definitive diagnosis. Once you have that you can make an informed decision.

I would let them live out their days until they get sick. If the problem is indeed Marek's there is nothing else to do about it. I don't think I would close the flock or get out of poultry keeping. There is a very effective vaccine on the market. As you lose birds, replace them with vaccinated chicks (which are only about a dollar more per bird at initial cost). You should be able to keep a relatively healthy flock that way. The infected birds are likely going to eventually die of Marek's, but some may not die for years. I would opt not to treat ill birds, but cull as they lose quality of life because you know that what they are ailing from is likely going to be fatal in the long run.

Sorry you are having such bad luck.

 

[Flock Leader]

Thanks for replying! I just thought I'd clarify life, as a rule, is hard for the small flock owner in Israel (that's where we live). Commercial hatcheries only sell to battery coops, not to private people, so when obtaining backyard chickens your only option is private breeders. Some claim their chicks are "vaccinated", but refuse to specify against WHAT, nor give evidence of the vaccination. So you really have to have an eye for trusty people.

I suppose our best option is to obtain fertile eggs (since Marek's doesn't spread from chicken to egg, as far as I understand?) and hatch them ourselves in an incubator, then raise separately from our old flock, as much as possible, for as long as possible, AND vaccinate? Of course if our old flock all dies out it won't be a problem...

but there are also wild birds.

In conclusion... hope to meet y'all in happier times.

 

[CMV]

Once you have had Marek's on your property, chances are good that you will always have it. My understanding is that it is long-lived in the soil. (If anybody has information to the contrary, please correct me.) So, usually, your only option if you have had Marek's is to get vaccinated birds from that point forward. The vaccine is not very expensive, but you waste a lot of it because it is sold in large lots.

 

[Gallo del Cielo]

Once you have had Marek's on your property, chances are good that you will always have it. My understanding is that it is long-lived in the soil. (If anybody has information to the contrary, please correct me.) So, usually, your only option if you have had Marek's is to get vaccinated birds from that point forward. The vaccine is not very expensive, but you waste a lot of it because it is sold in large lots.

Unfortunately, I think you're correct on this one. Here is a passage from a study I found this morning (the MD refers to Marek's):

Quote:

 

[Eggsoteric]

There seems to be a lot of conflicting information on how long Marek's can survive in the soil. It appears, to me, to run the gambit of a period of months to years and then one needs to take other factors such as climate, etc. into consideration. I don't think anyone can definitively say that Marek's remains in the soil for X years, especially given the circumstances such as those presented in the study. I have to wonder, had the farm in the study culled "all" their birds at the first sign of Marek's; disinfected; waited a period of time and had their farm retested before reintroducing any new birds, would Marek's have survived? Or, perhaps, since Marek's is so prevalent we should just assume it's everywhere "all" of the time.

 

[Gallo del Cielo]

There seems to be a lot of conflicting information on how long Marek's can survive in the soil. It appears, to me, to run the gambit of a period of months to years and then one needs to take other factors such as climate, etc. into consideration. I don't think anyone can definitively say that Marek's remains in the soil for X years, especially given the circumstances such as those presented in the study. I have to wonder, had the farm in the study culled "all" their birds at the first sign of Marek's; disinfected; waited a period of time and had their farm retested before reintroducing any new birds, would Marek's have survived? Or, perhaps, since Marek's is so prevalent we should just assume it's everywhere "all" of the time.

I agree. The first problem is that none of the studies I've read actually test the soil. It seems that most studies concern poultry houses and therefore focus on virus persistence on various substrates, e.g. wood, metal, litter, feather. As you note, environmental conditions are crucial to understanding virus viability. The virus is apparently more persistent in cooler drier conditions compared to hotter moist conditions. It also seems to be more persistent in feathers compared to other substrates. The study I quoted above was interesting in that the conditions were somewhat more close to what we experience as backyard chicken raisers (i.e. overlapping generations raised on the same property). I too would liked to have seen what would have happened had they removed all birds from the property for a period of time.

I also found this interesting study that examined the efficacy of feathers for monitoring persistence of various viruses. The authors cite earlier interesting studies of viability of the virus in feathers:


Quote:
I think it's possible to wait out the virus in chicken-free property under the right conditions. However, given that we can't eliminate the virus on our neighbors' properties, there will always be the possibility of the virus floating in on dust.

 

[Flock Leader]

Thanks for the interesting study quotes, I was never aware there could be connection between Marek's and temperature/humidity. The most populated areas of Israel are very hot and humid, but where we live it's cooler and drier. Marek's is not even on the list of obligatory vaccines for commercial breeders here.

I suppose that if it was here once, it will always be here. In that case hatching our own, then vaccinating, is our best option.

 

[ChickensAreSweet]

I have not dealt with Mareks, but here is something you can study as a possible differential diagnosis (botulism):


http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/205400.htm
following quote is from the above website:

"Leg paralysis is the only sign in mild intoxications, which must be differentiated from Marek’s disease, drug and chemical toxicities, or appendicular skeletal problems. In waterfowl, botulism must be differentiated from fowl cholera and chemical toxicities, especially lead poisoning."

 

[babsbag]

I started off with 9 chickens 3 years ago. They were from a good breeder and were not vaccinated. Her birds have never had Marek's. There are no other chickens within a mile of me, and the land was vacant when we build our home. When my third hen died, at about 8 months of age, I had a necropsy done. It was Marek's.

I had more than 9 chickens by then but I had hatched them out so no disease brought in by my new birds. I vaccinated all the birds I had at the time, even though I knew they had all been exposed. I didn't lose any more birds. (But I did have one plymouth rock hen that NEVER laid another egg. She was only 9 months old, laying everyday, unitl the vaccine...weird)

The next group of chicks I bought I had vaccinated, but I have bought birds from friends, hatched out some in incubators, and had broody hens. I no longer vaccinate new birds unless they are from a hatchery. I have seen no more evidence of Marek's.

I don't know if my flock really had it or not, but it seems to have gone away. I hope you have the same outcome.