Moving Forward- Breeding for Resistance to Marek's Disease

[tridentk9]

Cynthia, the article was how to increase the chances of enteritis  It's not really understood.  But it seems that rye and wheat are good for growing clostridium (enteritis bacteria).  Even tho cocci damage can leave an intestine vulnerable to clostridium, the method of allowing of clostridium causing enteritis is not fully understood.  It may be that some foods are harder to digest and stay longer in the small intestine.

I vaguely remember the form of the wheat being a major factor. Whole grain good, processed grain bad. But that may be extrapolating from two articles.

Remember that quote "No man is an island, entire of itself; every man is piece of the continent, a part of the main. If a clod be washed away by the sea, Europe is the less, as well as if a promontory were, as well as if a manor of thy friends or of thine own were: any mans death diminishes me, because I am involved in mankind, and therefore never send to know for whom the bells tolls; it tolls for thee." (John Donne) change it to "No disease is an island ....."

Back to Marek's Disease-

Resistance to MD is not a simple Mendelian trait but is highly complex and involves at least 14 separate quantitative trait loci (QTL). In addition, epistatic interactions between different QTL influence MDV viremia

 

[seminolewind]

Cynthia, sorry you lost her.

Trident, you're right, it's wheat and barley because they sit too long in the intestine.

Interesting about the QTL. Any more on that?

 

[seminolewind]

My friend and I had the same scare, same time. Both our hens, reproductive infection, hers internal laying. Both normal livers, hers had some minor worms, mine had a more dangerous type. Hers died before mine did and then a second one died out of the same pen at her place. She got her final report, 5 pages worth, mine still hasn't arrived. They tested for every known disease, I think.

The interesting findings were that the little D'Uccle hen had tumors in several places in her body, including her brain. The diagnosis? NOT Marek's. The tumors, which were apparently not really the main cause of death, were due to Autoimmune lymphoproliferative syndrome (ALPS), a non-contagious disease that is very rare. It's been seen in (gee, shocker) birds in Georgia, Arkansas and a handful of other lower states. So, this backs up what I keep saying. Not all non-reproductive tumors are Marek's Disease.

My long suffering Buff Orp hen died night before last. Karen, you read the thread about me draining all that fluid off her. She had two baseball size masses up where her left liver lobe should have been. No worms, no other tumors. Her heart pretty much gave out, body was full of blood, leaking out of her mouth. She's been doing this up-and-down thing for over 2 of her 3 1/2 years of life and her sister died strangely as well, so not related to whatever happened to this hen I had necropsied. Neither of those Orp sisters laid more than a handful of eggs once they started, then they just quit. She kept living, her sister did not. Hope had NO eggs inside, no internal laying. I believe this was a genetic disorder, in truth.

lalaland, I really hate mysteries. Sorry for your troubles. It's so stressful.

You're right, many tumors are not Marek's. Marek's is Marek's. That needs a pathologist to diagnose. And symptoms can vary widely. Most people are familiar with the classic Marek's symptoms. But are unaware of symptoms that fall outside those classic ones.

Cynthia, interesting about the ALPS

 

[speckledhen]

You're right, many tumors are not Marek's. Marek's is Marek's. That needs a pathologist to diagnose. And symptoms can vary widely. Most people are familiar with the classic Marek's symptoms. But are unaware of symptoms that fall outside those classic ones.

Cynthia, interesting about the ALPS

It is. I could only find reference to it with turkeys and humans, not chickens.

 

[lalaland]

seminolewind;

I must be tired. IWhat does PCR mean " I hope you get that Marek's PCR to cover NON symptoms". Could you explain it to me so I know what you meant?
thanks!

and I've been reading that mareks can leave the chicken with a depressed immune system, and stress will cause something to flare up, like cocci, and leave the chicken unable to combat it.

I'm going to have to start keeping better track of who had what symptoms, etc. I keep a pretty good eye on the flock, but some work weeks I am leaving before they are up, and back home after they roost, so there are sometimes 4 or 5 days when I am not really seeing them.

and Speckledhen, so sorry about your buff orp.

 

[chooks4life]

I vaguely remember the form of the wheat being a major factor. Whole grain good, processed grain bad. But that may be extrapolating from two articles.

Remember that quote "No man is an island, entire of itself; every man is piece of the continent, a part of the main. If a clod be washed away by the sea, Europe is the less, as well as if a promontory were, as well as if a manor of thy friends or of thine own were: any mans death diminishes me, because I am involved in mankind, and therefore never send to know for whom the bells tolls; it tolls for thee." (John Donne) change it to "No disease is an island ....."

Back to Marek's Disease-
I like the John Donne quote and the application to disease, very pertinent.

About the complexity of resistance to MD, I think it needs more investigating, because many vets, hatcheries etc find it comparatively quite easy to breed for resistance, and hence recommend it; I found it decidedly easy myself.

If it's so theoretically complicated, how do the results occur so fast? Thus far they've remained reliable and it's been years since I had a case, despite them being introduced to new flocks from other states of Australia fairly regularly... Others also found their results occurred rapidly too.

I wish we had some island somewhere, a remote one, possibly even an artificial one, where we could deliberately infect birds with all these diseases we're trying to compare and evaluate; that way we'd know for sure that a chook had been infected with current American, UK, Australian, Asian (etc) strains of MDV, for example.

I need to find a good vet and get my birds tested as soon as is feasible (moving house AGAIN lol)... Came across one that does great genetic testing, affordably, in my area, so hopefully I'll get some concrete info soon. Well, soon-ish... Got a lot on my plate right now. As do we all, I'm sure.

@lalaland - sorry for your loss and welcome to the thread.

@speckledhen - Were they 'hatchery type' Buff Orps or from a decent breeder?

Best wishes to all.

 

[speckledhen]

Quote: Surprisingly, both were from the same breeder as my 6 1/2 year old Orp hen Nugget is, a well known and respected one on BYC. They were beautiful and typey, both began laying around 32-35 weeks of age, laid only a few eggs, then quit and Gracie quit eating. We did everything to get her to eat, but she lost more and more weight and finally just died by the time she was a year and a half old. No other symptoms.

 

[chooks4life]

Surprisingly, both were from the same breeder as my 6 1/2 year old Orp hen Nugget is, a well known and respected one on BYC. They were beautiful and typey, both began laying around 32-35 weeks of age, laid only a few eggs, then quit and Gracie quit eating. We did everything to get her to eat, but she lost more and more weight and finally just died by the time she was a year and a half old. No other symptoms.

Has your breeder seen any similar symptoms with their own birds? Do you know if it's a common trait in their family lines? I'd have to doubt that both your presumably related Buff Orps suffer similar and rather uncommon problems with no familial precedent observable...

Seems to me that I hear pretty regular stories of Buff Orps having laying or reproductive tract problems. But I was thinking this was more a hatchery line problem.

When I first started out I got Buff Orps that were culls from a breeder whose birds all looked good on the outside but were riddled with faults including Leukosis (all of which faults she said not a word of warning about)... And they were always poorer, unreliable layers compared to others.

Anyway, best wishes.

 

[speckledhen]

Has your breeder seen any similar symptoms with their own birds? Do you know if it's a common trait in their family lines? I'd have to doubt that both your presumably related Buff Orps suffer similar and rather uncommon problems with no familial precedent observable... She isn't active here anymore so I haven't told her about Hope. I did tell her about Gracie back when it happened. I will try to send her an email and see if she's seen anything similar, but you know as well as I do how some folks take that. I am simply curious.

Seems to me that I hear pretty regular stories of Buff Orps having laying or reproductive tract problems. But I was thinking this was more a hatchery line problem. I had one hatchery Buff of my two die from reproductive gunk. The other lived to be the same age as Nugget is now, shockingly, the longest lived of my original ten hens. She had been broody twice, though she only raised chicks once. Nugget, from this breeder, had no issues, but she's been broody multiple times, so taken many long breaks from laying.

When I first started out I got Buff Orps that were culls from a breeder whose birds all looked good on the outside but were riddled with faults including Leukosis (all of which faults she said not a word of warning about)... And they were always poorer, unreliable layers compared to others.

Anyway, best wishes.

 

[chooks4life]

She isn't active here anymore so I haven't told her about Hope. I did tell her about Gracie back when it happened. I will try to send her an email and see if she's seen anything similar, but you know as well as I do how some folks take that. I am simply curious.

Hope it goes well. It's a pointless and harmful vanity for breeders to take it personally when someone says something that suggests their animals are less than perfect; no breeder in their right mind truly believes they have perfected a strain of anything, surely.

I wish there were a little more commonsense around such topics, it's always disappointing to hear that some customer in genuine need of information got the sharp edge of the tongue from some egotistical breeder. In my opinion, the breeder is under an ethical obligation to freely supply customers with information about known genetic or other problems in their lines. Suspected problems are always worth mentioning too.

Good luck with extracting info without hitting the ego vein.