I knew the basic things to look for when it to came Marek’s Disease Virus (MDV). I’d read The Great Big Giant Marek’s Disease FAQ here in the articles section of BYC. I’d followed the links and read some more about it. Then I promptly moved on until I had cause for concern. When I became convinced that Marek’s is what was killing my flock, I began to do more research about it. As it turns out, it’s more prevalent than many people might think.
We’ve all heard about bird flu in the past, and I’m sure many of you have heard about the recent virulent Newcastle Disease (vND) outbreak in California. What I haven’t ever heard about, and we aren’t likely to, is an outbreak of MDV.
Vaccine development for MDV began in the 1960's. Today, both meat growers and egg producers vaccinate for MDV along with a lot of other things. If you order chicks from hatcheries, you have the option of having them vaccinated before they’re shipped, or not. As it turns out, the vaccine doesn’t prevent chickens from contracting MDV, but it can prevent them from developing tumors which are what leads to paralysis and often death.
According to a report published in 2001, 202 samples of human blood were tested, and 20% tested positive for MDV. It didn’t matter whether the test subjects had been directly exposed to chickens or not. How did it get there? It stands to reason that humans are eating chickens infected with the virus. It also stands to reason that since not everyone gets their food from a single source, this is a fairly widespread issue.
Humans have been eating chickens for a long time, long before we even knew that MDV existed. It is not known to transfer to humans via eggs or meat. In fact, there was a previous attempt to link MDV to multiple sclerosis in humans via DNA and scientists weren’t able to do so.
According to the USDA, roughly 1% of households in the U.S. owned chickens in 2013. Another 4% planned to have them within the next 5 years. With the popularity of backyard chickens increasing, it stands to reason then that the risks we face as backyard chicken keepers are changing as well. Complicating this growth in popularity is the fact that some humans care for animals and their living conditions more than others.
This article will explain how to sanitize your coop if you have, or believe you have, MDV in your flock. The USDA recommends that you sanitize your coop whenever you add chicks and some sources suggest at least once a year.
Please note that my flock doesn’t have confirmed Marek’s, but based on the presentation of symptoms I strongly suspect it. I currently have 12 chicks that were hatched here and were exposed to the Marek’s suspects. The sick birds have been put down and we’re moving on as best we can.
Before I get started, I do want to tell you that I’ve always had the habit of checking my birds over once a month. I do it during the full moon because that’s how I remember to do it. I can’t stress the importance of this enough. It’s how I was able to keep an outbreak of lice down to a slight bump in the road last summer and how I was able to know for sure that more than one chicken in my flock was sick this year. Chickens are very good at hiding things.
About how things are set up here: There is no run, my chickens have access to the entire backyard from dawn to dusk. My coop is located in a side yard. It’s 8’ x 12’ and walk in, enclosed on three sides with plywood and the front is covered in hardware cloth. I do have the option of covering the front with wood panels in inclement weather. The roost is 12’ long with a poop board underneath that I used PDZ on. There are usually three nest boxes hung on a wall and the floor is bare dirt, although it has been covered with hay or pine shavings in the past. The maximum number of chickens in this coop at one time was 9. Here it is prior to clean out
I used Virkon S to sanitize the coop interior. I was able to purchase this online for $20 plus shipping and it was here in 3 days. There were 50 tablets in the bottle and I only need 8 per gallon of water, one gallon was enough for the entire coop. I had more than enough to make some in a bucket to clean tools and nest boxes and there's enough left to clean again next Spring. The product description states specifically that it kills the Marek’s virus. You can also use ACTIVATED Oxine, but it has to be activated.
Before cleaning with the disinfectant it’s important to clean out all the litter, debris, and fecal matter and give your coop a good scrubbing with a brush, detergent and some warm water, then rinse and let dry. Pay attention to corners, cracks and crevices where litter, dust and dander tend to build up. Be sure to let it dry out before you apply the disinfectant, you don’t want to further dilute it on wet surfaces. Then follow the instructions for use on the product label.
I used a Shop Vac with a fine particle bag. A crevice tool and brush attachment will also come in handy. You can purchase a 5 gallon Shop Vac at Walmart for $45, the fine particle bags are $10 to $15 depending on where you buy. I have an extra bag for maintenance so I can vacuum the dust from my coop rather than sweep it to the floor. Dust in the coop WILL have dander, a major source for the spread of MDV.
I used ¼ c Dawn dish soap per 5 gallons HOT water and a scrub brush for the roosts, ramp and poop board. I keep the roost clean with a scraper and sand paper weekly which really made the scrubbing part easy. For the walls I used fresh water and soap at the same dilution and a washcloth with a scrubbing net type surface on one side.
There were some areas on the poop board like the one shown below that were especially dirty despite scraping and scrubbing. I cleaned these with sand paper and rinsed again. Then dried over night.
I applied the disinfectant per the instructions with a garden sprayer, $7 at Walmart, and left it to dry.
Some people paint the interior of their coops to seal the wood which can help deter pests, not to mention the aesthetic appeal. I much prefer natural wood but decided to whitewash the interior of my coop this year. Whitewash doesn’t have the odor issue that comes with paint and is mildly antibacterial which can help with mold and mildew. It is reported to deter pests including flies and it's also nontoxic.
2 cups salt, $0.48 at Walmart
1 gallon water
6 to 8 cups hydrated lime; Wear a dust mask when handling in powder form; this is also known as Type S and is located in the masonry section at Home Depot or other similar stores. It is NOT garden lime. 50# bag $12 at Home Depot. It'll last a while.
I used a quart of boiling water to dissolve the salt in a bucket, then stirred in 3 quarts of cool tap water. Be sure to stir while adding the lime a little at a time until it has all been absorbed. I used a wooden stick.Then paint as you normally would.
I found that the older wood took the wash better than the newer, but in both cases the second coat was faster and seemed to smooth things out and make the look more aesthetically pleasing.
I've eliminated PDZ or anything with a granular consistency because it tends to be dusty. Since I was using it as a litter under the roost this could potentially create a build up of dander as well. I suggest using newspaper or old feed bags that can be removed and replaced each week.
I would like to point out a very useful hack I came across here on BYC. I can't remember who posted it on which thread, but I learned that a vinyl strip curtain over the pop door can keep small birds out of the coop. You may have to train your chickens to use it, but it's easy. We lowered one slat a week at night so that they learned they could push through it like a curtain. Wild birds can visit other coops and flocks, potentially spreading disease or pests along the way. I purchased this from Chewy for $20. Yes, I probably could have made something cheaper but honestly, I didn't feel like it.
In closing, it's important to regularly clean the coop, turn over the bedding if you use it and scrape the roosts. Dusting with a shop vac will go a long way toward keeping the dust down. I hope you're convinced to add sanitizing to your routine once a year now as well. The process was simple and, depending on your coop, could easily be done in a day.