Lymphoid Leukosis... Thoughts and experiences please

[spiderlady]

Ive been losing birds here and there for two years now (since I first got chickens in spring 2015). I had thought Mareks the culprit and have done a lot of research on that disease and the possibility of breeding for resistence etc. However I finally found a vet who would do a necropsy for me for free (instead of charging a fortune) and he determined that it is more likely Lyphoid leukosis. SO. I dont know tons about it as Im starting over now in my frenzied research (lol), but one of the things I read is that it can be passed vertically from hens to the eggs and even genetically through egg and sperm.

So Im wondering is breeding for resistence still feasible for this disease, and if so, how would you go about it? I am down to a few hens and one roo, and these all seem healthy survivors who have never been sick as far as I can tell, but they have been with the sickies so are they carriers? Would they pass the virus to eggs (even if raised separately) even though they are not stick? If I choose not to cull and startover (the surest bet at this point) should I incubate and introduce or see if I can get a broody to hatch some? These are the questions floating around in my head today!!

I hate the idea of trying again to introduce older chicks that Ive raised for several months and then watching them die one by one....

Ugh. If anyone has any actual experience with or knowledge of this disease, I would love to hear it. I may still cull all,or just wait a year or so and see if they die, but I would like to know if breeding for resistence can be done.

 

[Wyorp Rock]

@azygous has experience with Lymphoid Leukosis. You may want to pm her or she may be along shortly.

I'm sorry you are having trouble, I wish you the best.

 

[azygous]

Here I is.

Yes, indeedy, I have experience with LL. My flock has been confirmed to carry the virus. And yes, I have had the experience of seeing the virus passed vertically from egg donor to chick. That's very heartbreaking. The disease is extremely contagious and is passed horizontally from rooster to hens through mating, from hen to hen through dander, feces, and air currents. No one escapes infection.

All is not as gloomy as it would first appear. The virus is short lived in the environment so it's not easily transported significant distances to other venues. Also, while all my flock carries it, most are resistant to the virus. I don't know why some get it, but most remain asymptomatic for their entire lives. I have a nine-year old Brahma hen who is healthy and active.

It's also not necessarily a given that all chicks introduced into the flock will sicken and die from this virus. I would estimate that my loss rate of hatchery chicks during the first year is no higher than in any flock. Most of my new chicks obtained from hatcheries over the past four years have thrived. Yes, there are individuals that have showed symptoms, but out of twenty-four chickens, there have just been three in the past couple years.

I have had a very high morbidity rate though with eggs set under broodies to hatch. But I had one success this past summer, and the chick is almost six months old and seemly healthy, approaching point of lay. I want to try again in spring. I'm an optimist.

As for breeding resistance, that's what most hatcheries have been doing over the past decade, but usually in the production breeds. The specialty breeds such as Brahmas seem to be vulnerable and not very resistant. Don't let it stop you from experimenting. I don't see why you can't select healthy individuals who have made it through their first two years and breed them for resistant stock.

Any questions on anything I failed to cover, please feel free to ask.

 

[spiderlady]

Thanks for sharing your experience. Im kind of torn on what to do, because I had aspired to raise pure bred Russian Orloffs, but I cant afford to keep bringing in new expensive purebred chicks (tried that twice!) just to have them die. I would have to scrap what I have and start over. In my little mixed flock I only have one Orloff hen left and no Orloff roo to breed. I do however have one huge, healthy barnyard mix roo, and the scientist in me likes the idea of experimenting with breeding tougher, healthier disease resistent chickens for my laying flock. My one Orloff thats left aint the prettiest as far as the breed goes, but she survived some kind of disease as a chick (too young to be LL I guess, but wasting was the main symptom liken LL) and is now my best layer. So good survival genes I think?

It sounds like if I let a broody hatch chicks its less work for me, and strong selection pressure early on too I think for weeding out the weaklings before I feed them for months and name them and get attached... But none of my girls have ever gone broody for me. And it would be so much easier (well kind of in a way ) to just kill the rest and bleach everything.

Sorry for the rambling. Ill probably wait till spring to decide what to do with my little remnant flock. Maybe nothing. *shrug* Before all this I promised my 4 yr old I would never kill his polish. :0

 

[azygous]

The best way to deal with the LL virus is to cull the entire flock if you have the stomach for it, disinfect the premises, wait a decent interval for the virus to peter out in the soil, and then start all over. I so wish I could do that, but I don't have any long term goals so my chickens will just grow old along with me. In your case, be thankful it's not Marek's. LL permits a do-over.

Do you have any inkling how the virus was introduced into your flock? In my case, I'm pretty sure it came with the first three adult hens with which I began my flock since all new additions have been chicks from reputable hatcheries. LL is so short lived in the environment that it usually hitchhikes on an infected individual chicken. I'm so isolated from other chicken owners, let alone other people, it shouldn't have been able to get anywhere near my flock. The friend who gave me the first chickens was the only chicken owner within twenty miles.

 

[spiderlady]

I think it came from a pair of cockerals chicks I got my first year. Hoping for pullets of course lol. They actually both almost died right away from cocci, brought on from the stress of moving to a new place no doubt. But I had them separate from my flock still and treated them with corid and all was good after that until a few months old, then they both died.

Im actually not 100% confident that its NOT marecks, although im trying to believe its LL because thats what the vet said it looked like. He said he didnt see signs of Marecks. Im guessing that means no nerve involvement. But I dont think that necessarily rules it out. The reason I suspected Marecks is becaise those first two cockerals,as well as 3 other hens (5 out of 16 losses total) have indeed showed nerve involvement by losing coordination and eventually going down in the legs altogether. The rest have just wasted as you would expect with LL but that can also be the case with Marecks I think. But I had let the vet know that and he said he thinks LL so... I hope for the neighbor chickens sake thats true.

Yeah I really should just start over. Other than wanting a larger flock for more eggs though, Im not really in a hurry to do it. Its sad to kill animals that arent sick (visibly) and arent intended for food. Ive killed enough this year though (mercy kills for those that were dying) that I guess its do-able, knowing that this will only continue if I dont.

So if it were Merecks, it would just take longer to leave the property right? I in AK. Surely a year in the freezing weather with no host would kill it? I would be so devestated if I killed my flock to start over and it turned up again. :0

 

[hooktontravel]

following this. i'm waiting for histology to find out if my 7 mo. cockerel died from a neoplasm or some other sort of tumors. thought I was doing well going with local, npip breeder stock, but maybe not.