Hi, I am also trying to something similar to the original poster of this question, and I was wondering where you have gotten your information that points towards needing to keep the sick chickens alive as the best specimens to breed from? It seems contradictory to all the other information I’ve been able to find so far, but I really want to get the whole picture on this. Any further research I can do would be great, if you can point me towards where you learned this. Thank you!
Sadly, I don't have a source I can point you too. I was working a catering gig for an ag science event and while offering up hors devors to a group overheard part their conversation on viral resistance in farm stock. They were a virologist, 2 geneticist and a stack of animal husbandry students. Having no problem inserting myself into a conversation, I butted in and joined the conversation. I had questions and when would I ever have an opportunity like that again. Seriously, who wouldn't?
I got a lot of answers. Marek's affects birds younger than 30 months, it's more severe under 20 months. After 3 years, the immunity to the virus would be in all of the birds DNA and at that point it would pass to the offspring as a resistance. Several (they said 3) generations of resistant birds who developed the disease would generate resistance to the point of immunity. That immunity line could be maintained as long as the parentage is from birds with immunity. Once birds with resistance start being bred to birds without it, the resistance would weaken. I asked about breeding a third generation bird to a first generation bird. They said as long as enough time had passed for the resistance to attach to the first generation birds DNA, the offspring would have the higher resistance of the third generation.
I got pulled back to the kitchen before I could get contact info. Fraternizing with guests is highly 'frowned upon.
I did run across some information to that effect in several studies I glossed over, but at the time it wasn't the topic I was focused on.
These are my search sources. They pull up WAY more than Google.
refseek.com
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Encyclopedias, monographies, magazines
worldcat.org
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link.springer.com
Scientific research protocols sources
bioline.org.br
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repec.org
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Science.gov
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