Moving Forward- Breeding for Resistance to Marek's Disease

[chooks4life]

Okay, so what is the difference between vaccinating with HVT, vs. exposing them to HVT via turkey dander, droppings, etc? Why is one of these considered 'masking weaker birds' and the other not?

Possibly because the vaccines prevent most susceptible birds from dying outright.

Statistically speaking, there's far greater risk of viral mutations occurring in even non mixed flocks where combination vaccines are used, and/or strong chemical/artificial treatments, than from species mixing as they naturally do.

Please understand, I am not trying to be argumentative, but can you provide any sources that support this?

It's been documented in hospitals and laboratories for decades, as well as 'in the field' in veterinary science... :/

Your very response there, asking for sources, is in response to a post containing one source I cited.

If you've somehow not been exposed to that knowledge before, then I suggest you do your research (not trying to be rude) because I haven't been collecting sources to back up future statements of something that is so widely known and accepted, since naturally I foresaw no future need for it, lol!

You do understand that viral mutations are spontaneous and either go on to be a successful mutation (more easily overcomes the immune system-- thus, more virulent) or an unsuccessful one (does not survive the immune system's attack) regardless of method of exposure, but is in direct interaction with immune response?

Yes. I do understand that. What a bizarre question. What's your point?

 

[tridentk9]

Edited to add the actual comment from the necropsy: The histopathologic findings in the brain, heart, lung and skin in addition to the clinical history are suggestive of
Marek’s disease caused by gallid herpesvirus 1. [/I]

I kept looking at this thinking it didn't make sense. I finally had a chance to really think about it.

Marek's disease virus(MDV) is a member of the Alphaherpesvirinae subfamily of theHerpesviridae. Based on virulence for chickens, ability to induce T-cell lymphomas, and antigenic properties, there are three serotypes of MDV (MDV serotype 1 [MDV-1], MDV-2, and MDV-3). MDV-3 represents the herpesvirus of turkeys (HVT) which has been widely used for vaccination against MD. According to the most recent nomenclature, MDV-1 is classified as gallid herpesvirus 2 (GHV-2), MDV-2 is classified as GHV-3, and HVT is classified as meleagrid herpesvirus. All three viruses belong to the new genus Marek's disease-like viruses within theAlphaherpesvirinae,

We've been discussing gallid herpesvirus 2 (GHV 2) formerly known as MDV 1. Gallid Herpesvirus 1 is Infectious Laryngotracheitis. Probably just a silly error.

 

[seminolewind]

Quote: Glad you took this to be humor.

 

[speckledhen]

Glad you took this to be humor.

You are nicer than I am. Sometimes, you should hear me yelling at my monitor over stuff on BYC, then the tactful former realtor self kicks in and I don't say exactly what I am really thinking.

 

[seminolewind]

Hi y'all,

no I don't think you are after me ;O) -- And I don't think anyone is being argumentative --- and I hope I don't sound that way LOL -- What I think is that everyone here is trying to pile all the possible facts on the table - including anything new, not yet considered, a different viewpoint etc. and hope to sift through it all and get more truth than we had before.


On a different note - regarding exchange between chooks4life and Nambroth There was an instance in Australia BTW - that I heard of long time ago when I first started researching Marek's where somehow in Australia them mixed the USA vaccine and the UK vaccine. You know that there are different strains in each country - and the result was a highly resistant Marek's that responded to neither. I don't have the quote/source at hand, but I did just want to reinforce what chooks4life was considering for us.



ETA - thought if I did a quick google I may find the article - but I didn't. however I did come across this report which I skimmed.
https://www.aecl.org/assets/RD-files/Outputs-2/UNE-83JA-Final-Report.pdf

The commonalities are that it is from Australia and it is about Marek's - There are some photos of tumors/infected organs in the report that could help reference for those who did their own necropsys. It is an interesting read. If I find the article I will come back and post a link. Again, this was some years back so I don't know if I will find it - I think it was a newspaper or magazine article......

Of course I cannot find it - which makes me question my memory-
but this from Poultry hub - does talk about some of the problems that Australia faced yeas ago and some of their approaches.

http://www.poultryhub.org/health/disease/types-of-disease/mareks-disease-virus-or-mdv/

I really thought that you were doing like I do. I throw up links that have information regardless of whether I agree with it or not hoping it will help someone understand some things better. It's unfortunate that there is so much old and redundant information on the web that's not dated. And that gets confusing when old information is not dated.

These links are very interesting. I haven't finished the first with 77 pages, LOL

 

[seminolewind]

Quote: We've been discussing gallid herpesvirus 2 (GHV 2) formerly known as MDV 1. Gallid Herpesvirus 1 is Infectious Laryngotracheitis. Probably just a silly error.

Maybe we should put together a print out chart so we're all on the "same page"

 

[PetRock]

I kept looking at this thinking it didn't make sense. I finally had a chance to really think about it.

We've been discussing gallid herpesvirus 2 (GHV 2) formerly known as MDV 1. Gallid Herpesvirus 1 is Infectious Laryngotracheitis. Probably just a silly error.

Hah! So the person who did the necropsy either made a mistake or is mistaken?! I copied that sentence right from the report.

 

[Nambroth]

I kept looking at this thinking it didn't make sense. I finally had a chance to really think about it.

We've been discussing gallid herpesvirus 2 (GHV 2) formerly known as MDV 1. Gallid Herpesvirus 1 is Infectious Laryngotracheitis. Probably just a silly error.

Is Marek's now officially known as GHV2? (Instead of MDV1)?
I want to make sure I don't inadvertently confuse someone worse than I already do...

 

[speckledhen]

Just when you have the number-letter combo down, they go and change it on you. My brain has a long turnaround time and it may not compute. Oh, well, I stay confused anyway.

 

[tridentk9]

Maybe we should put together a print out chart so we're all on the "same page" 

We can still use either MDV1 or GHV2, or even just use "Marek's Disease" for the disease itself. Though to confuse it even more- an article or two uses GaHV2!

If the pathologist though was going to name a specific gallid herpesvirus, they should have known it was serotype 2 for Marek's Disease. Similar to a Ford salesman talking about "that Chevy over there, the blue Fusion". It would be OK for me to mix brand and models up- but a salesman that sells that model car?