Moving Forward- Breeding for Resistance to Marek's Disease

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Ivermectin is ineffective against cecal and capillary worms. Large roundworms have built resistant to it as well. I quit using it. Capillary worms are a type of roundworm, often called hair or thread worms.

I got lazy and it's easy to use Invermectin Pour-on. And it's cheap as well. But, my biggest mistake was that I continued to worm my birds as if they were all free ranging all day, every day. Back then, worming wasn't as needed as it is now, when they spend much more time in pens (which are all down to dirt, of course). Everywhere on the web says Invermectin does kill capillary worms, but apparently, as you said, not very well, since my hen had them in several locations. So, probably just used it too much without changing up the program.

Safeguard paste or Zivermectin Gold is the best I can do until more money comes in (and Jim, you know what I'm talking about, dontcha?
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).

Also, I probably have more of a worm issue with rotting leaves, being in the woods. Worms love that. And my hen sure loved those fat slurpy worms. She also had a massive reproductive infection, which left her more susceptible to worms, I guess.

Dottie, my broody BR, won't touch them and she's teaching her chicks to avoid them as well. Good girl.
 
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LOL-George you read my mind. I was thinking a brooder pen that could be taken apart when not needed, or at the least the roof off, specifically to let the sun in. While heat doesn't kill MDV the sun should help.

Taking apart the brooder pen should help get all the dander out and allow more complete use of disinfectant. Worth noting again and again is that disinfectants rarely work well unless the area is clean prior to application. Depending on the disinfectant, some have a limited life once diluted, others need a minimum contact time and some need rinsing.

And one of those thoughts in the middle of the night... Just because the chicken has Marek's Disease does not mean it has died of Marek's Disease.
The best advice I found, and I stick to (mostly) is a dry clean, wet clean, then disinfect.

Some of my mobile pens get flipped upside down or on their sides to dry in the sun. I believe in taking advantage of the sun and fresh air. I like free, LOL.

I put a good effort into it, but I do not want to get too carried away. Sterile is not what I am looking for necessarily. I believe in breeding for health and vigor, but in a well managed flock. Too often I have seen the breeding for resistance as an excuse for poor management.
 
I agree completely, George. Unfortunately, I don't have any mobile anything-no way to do that on completely uneven ground and have it predator proof. You know, I've observed that it's the kids whose moms are always slathering on the hand sanitizer that always seem to be sick. No resistance at all.

Healthy chickens are able to carry minor worm loads. It's when they are not healthy or the worms completely overwhelm the system that you have an issue. I am not a quarterly wormer and I will never be. I have laying hens and they must live on this ground so must be able to deal with what is here. I will now make sure I worm each flock twice a year with a good wormer, but I think some worming programs go way overboard.
 
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Found this online, not a common subject with chickens, but since my property is like an ammo dump with shell casings from .22's and buckshot all over the place, in addition to burnt foil (why, no idea) I was researching it and thought I post my findings:

http://naturalchickenkeeping.blogspot.com/2013/03/lead-and-zinc-hidden-dangers-to-your.html

The first list is regarding lead toxicity.

Quote:
Depression
Failure to grow or to maintain weight
Loose stools – greenish-black in color
Lack of balance
Disorientation
Inability to perch
Vomiting
Brain function disturbance
Loss of coordination
Loss of vision
Seizures
Inability to hold head straight
Death


Signs of zinc poisoning in chickens include:

Loss of appetite / weight loss
Feather picking
Shallow breathing
Depression and lethargy
Weakness and shaking
Loss of balance
Diarrhea (in advanced cases stool may appear black and tarry)
Vomiting
Kidney, liver and pancreatic anomalies
Anemia
Death

....and a funny for you from that article, since we all need to laugh:


Quote: Oh wait… that’s not right.


A list of possible sources for contamination on your property, taken from a different article:
Quote from http://www.birdclinic.net/avian1.htm This part is of interest to me, concerning paralysis and possibly lead toxicity mimicking Marek's symptoms:

Quote:
 
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Lead is very common in the environment where humans have lived in the last couple hundred years. Especially old farmsteads and hunting camps that have since been either developed or are still being used today. It doesn't take much lead to adversely affect our birds. The smaller the bird, the less it takes. A single lead BB from a shotgun shell is enough for many birds, even #7 or #8 shot which are one of the smaller shots used commonly. How often do our birds eat hard, round little pebbles? I remember a thread here on BYC about a lady whose birds gobbled up those plastic Airsoft pellets and when she processed them their gizzards were full of all sorts of crazy stuff.
There is a test for lead, but it is expensive. I had it done for my current rooster when we couldn't figure out what was wrong with him. It didn't end up being lead, but my vet says she sees it pretty often.
 
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Breeding for resistance. I was looking up enteritis last night (obsessing) when I came across an article on World Poultry News about Building resistance to chronic enteritis in broiler flocks. (2011)

I didn't know there was such thing as chronic enteritis, and I'm still not clear on how a chicken survives with chronic enteritis.
However, the suggestion seems to be that farms increase the digestible protein and vitamins and minerals that seem to increase resistance.

I hope I get this right; because their antibodies are being switched on and off by this chronicity that comes and goes, it burns up all the proteins and vits and minerals that the other parts of the body need. There is a hierarchy of what gets nutrients first, starting with the brain, heart, lungs, and digestive system, then to lesser important things like feathers .They say the cause of this chronic condition is unknown, so they are fighting something with an unknown cause. However it's become more prevalent since many farms have reduced or eliminated their use of antibiotics in feed.

Any stress like even change in feed or weather can trigger this (I think life is stressful, never mind the heat cold food being late for treat time). I just wonder why my necropsies show enteritis, it may be due to whatever killed them. However, the article says the cillins, and others will treat the enteritis, and the change in diet will help the chicken fight it off.

So I'm posting this in case there's anything that can relate to breeding for Marek's resistance.

If anyone knows of anything published about chronic enteritis let me know. It's hard to find articles, I"ve only found 2 so far.
 
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Cynthia, lots of illnessis mimic Marek's and Marek's mimics lot of other illnesses. I think the bottom line would be on necropsy, finding gross tumors, microscopic tumors, and enlarged nerves. Tumors, to a pathologist, all have tell-tale differences. A pcr is one step further . All 3 results are taken into consideration to form their opinion.

The lead symptoms are interesting. I wonder what parts of a chicken can be tested for that? Feathers?
 

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