Breeding for Marek's resistance

[Isaiah53]

If this post should be under breeding instead, please let me know and I'll repost there....

Does anyone have information on the who, what, when, why etc on breeding your flock against Marek's Disease?

My flock was diagnosed recently with 2 hens that died of Marek's Disease. Rather than culling or living with the disease randomly killing my 100+ flock in the future I am trying to gain knowledge on whether it's worth attempting to breed for Marek's resistance. My chickens were left with me from the previous owners. They did not vaccinate. Getting the vaccine is next to impossible.

Any direction is appreciated!

**Edited to add, I recognize the vaccine needs to be administered at 18 days in the shell for the best results or at hatch within 36 hours. I also understand they need to be quarantined for upwards of 3 weeks to build an immunity after the vaccine. My question really is about breeding for resistance.

 

[roosterhavoc]

Its been said that most every back yard flock has already been exposed to mareks. There’s different strains so who knows. Put down weak birds, put down birds that get sick often, and only breed the strongest birds that are clearly thriving. Can’t go wrong with that approach. Taking extraordinary measures to save and nurse sick birds isn’t doing any flock any favors.

 

[oldhenlikesdogs]

Cull all that come down with symptoms, and breed all healthy adults. I see Mareks in a young bird or two a season. We remove them as soon as it's apparent. Don't try to treat sick birds, cull. The birds that show no sign of illness should be resistant.

Keep stress lower too as young birds mature to help them build a healthy immune system. So that means make sure older birds aren't harassing them constantly, and remove extra males as they start to make trouble. Don't crowd, or confine birds too tightly. Exercise and fresh air makes for stronger birds.

 

[Isaiah53]

Cull all that come down with symptoms, and breed all healthy adults. I see Mareks in a young bird or two a season. We remove them as soon as it's apparent. Don't try to treat sick birds, cull. The birds that show no sign of illness should be resistant.

Keep stress lower too as young birds mature to help them build a healthy immune system. So that means make sure older birds aren't harassing them constantly, and remove extra males as they start to make trouble. Don't crowd, or confine birds too tightly. Exercise and fresh air makes for stronger birds.

Thanks for this advice. And, the good news is I already do this. My birds are separated based on age because they're fed different feed for their ages. Up to 6 weeks medicated chick feed (because I don't know what was on this property before us the previous owner had a petting zoo here). From 7 to 18 weeks they're fed a grower feed (this one I'm considering changing as it's 18% grower and I was advised by another person maybe it should be increased but I can't find a higher protein feed here that has no calcium). Then my layers 18 weeks and up are all in a separate area and fed a 20% layer feed with 5 % calcium. I understand there's another feed that has lower calcium 3.5% but the quality looks not as good either...but I'm working on that.

The other problem is the strain. Mine showed no symptoms whatsoever and simply died. There was the day or two before I noticed one of the two was lying in the sun and both were having a very light molt, but nothing else, although in hindsight their quietness could have been lethargy and keeping to themselves (typicalffor them as they're lower down in the pecking order) and the only real "sign" . Had only one died, I probably would have just buried it. But since two died (the first overnight the second two hours after I'd found the first one) it's what made me suspicious. But that's my problem at this time of year, the lethargy, staying away from others could be from molting as well.

 

[Isaiah53]

Cull all that come down with symptoms, and breed all healthy adults. I see Mareks in a young bird or two a season. We remove them as soon as it's apparent. Don't try to treat sick birds, cull. The birds that show no sign of illness should be resistant.

Keep stress lower too as young birds mature to help them build a healthy immune system. So that means make sure older birds aren't harassing them constantly, and remove extra males as they start to make trouble. Don't crowd, or confine birds too tightly. Exercise and fresh air makes for stronger birds.

They also have designated grow out pens that are huge for their age and size, the 6 to 18 weeks have half an acre to roam freely while being secured and the older ones 18 weeks and up have 1 acre secured pen area but also allowed to free range on up to another 15. Lots of peace and quiet for them

 

[oldhenlikesdogs]

Thanks for this advice. And, the good news is I already do this. My birds are separated based on age because they're fed different feed for their ages. Up to 6 weeks medicated chick feed (because I don't know what was on this property before us the previous owner had a petting zoo here). From 7 to 18 weeks they're fed a grower feed (this one I'm considering changing as it's 18% grower and I was advised by another person maybe it should be increased but I can't find a higher protein feed here that has no calcium). Then my layers 18 weeks and up are all in a separate area and fed a 20% layer feed with 5 % calcium. I understand there's another feed that has lower calcium 3.5% but the quality looks not as good either...but I'm working on that.

The other problem is the strain. Mine showed no symptoms whatsoever and simply died. There was the day or two before I noticed one of the two was lying in the sun and both were having a very light molt, but nothing else, although in hindsight their quietness could have been lethargy and keeping to themselves (typicalffor them as they're lower down in the pecking order) and the only real "sign" . Had only one died, I probably would have just buried it. But since two died (the first overnight the second two hours after I'd found the first one) it's what made me suspicious. But that's my problem at this time of year, the lethargy, staying away from others could be from molting as well.

Chickens often do drop dead for no apparent reason. About half of mine do, the other half act sick, and we cull. I find I experience about a 10% lose every year from various things, so it may not necessarily be Mareks killing your birds. I see more random deaths during spring and fall because of the stress of the seasons changing, and the general wetness that occurs during those times of year.

Since we cull all symptomatic birds when young I have never seen an adult exhibit Mareks symptoms.

Your feed sounds good and appropriate. I like an 18% grower as I don't want my pullets maturing early and prefer slower maturity.

 

[Isaiah53]

Chickens often do drop dead for no apparent reason. About half of mine do, the other half act sick, and we cull. I find I experience about a 10% lose every year from various things, so it may not necessarily be Mareks killing your birds. I see more random deaths during spring and fall because of the stress of the seasons changing, and the general wetness that occurs during those times of year.

Since we cull all symptomatic birds when young I have never seen an adult exhibit Mareks symptoms.

Your feed sounds good and appropriate. I like an 18% grower as I don't want my pullets maturing early and prefer slower maturity.

The two were brought in to the vet for a necropsy. They were about 3 years old. Vet says there were tumours everywhere and diagnosed Marek's but if anymore die I'll send it off to our provincial health lab for a tissue test. I'm thinking it's Lymphoid Leukosis based on age and the fact the young ones would have been affected as well and should have had some die by now.