Hello all! This will be a wall of text for you guys to read to give some backstory. Who knows, maybe you'll learn something! TL;DR version at the bottom.
I purchased a new batch of starter pullets this spring. I had left my flock behind when I made the move from VA to MA for a new job. Luckily, I was able to find a lady to rent a room from that was also cool with me building a run to protect the coop she already had in her backyard! Unfortunately all of her hens had been picked off by various critters in the neighborhood (probably a raccoon or fisher cat) before I had moved in. With the coop already in place, all I had to do was build a run using the foundation of an old shed/workshop as a guide. I was living the dream!
I should have been more suspicious in retrospect, but at the time I was too excited. When I was digging post holes around the interior edges of the foundation I started to notice a bunch of random broken glass and metal and the like. Apparently the people who lived there way back in the day just buried all their junk instead of throwing it out. Classic country stuff. Anyway, after several trips to the dump I had succeeded in getting most of the little bits out and built the run. I got 8 pullets on Memorial day and got them all situated and happy.
About a month and a half later I noticed one of the Marans standing off by herself and struggling to breathe. She also wasn't really reacting to my presence either; she had been one of the more skittish ones in the past. She didn't even try to get away when I picked her up and put her in another holding cage to keep her overnight so I could take her to the vet in the morning. Unfortunately she died about 20 minutes later or so. I made the mistake of putting her body in the freezer to keep it from stinking up the joint overnight so I could get an autopsy in the morning, but I guess the freezing process prevents that. The other 7 seemed fine, so I just brushed it off to some odd thing and didn't think anymore of it.
About a month later I noticed that one of my Wyandottes was looking a bit thin. She ended up just dying one night. This time I was able to call the vet, describe what I saw, and set up an autopsy for an hour later. The vet asked me to bring in one of the live hens to do a blood test for lead poisoning, as I guess that's a somewhat common problem in these old New England houses/properties.
Sure enough, the hen I brought in had 23 dg/ul of lead in her blood (at least I think those were the units). "Normal" levels are anywhere from 0-2 dg/ul. The hen that had died was just septic. I guess she had gotten so weak from not eating (which was a result of the lead poisoning: brain damage in the area that provides the drive to eat) that her normal gut bacteria just took over.
I ended up asking my next door neighbor who has 3 little kids if he had ever done any lead testing in the soil on his property. He said no, and when he asked why I told him what happened with my chickens. He said that made sense, as apparently the guy who lived in my house ~30 years ago used to paint buses and trucks for a living and that the foundation of the building I had used for my run belonged to his paint storage shed. So I can totally see that he might of had leaky cans or was just dumping his paint thinner full of leaded paint after cleaning his brushes straight into the ground, along with who knows what else.
I work for an analytical instrument manufacturer and was able to actually do some lead testing myself. I took some of the soil from the coop and analyzed it for lead with one of our prototype instruments. It turned out the amount of lead in my coop soil was about 15x as high as the random patch of soil I dug up from the grass in the front of our office! It was safe to say that the hens were picking the lead up from scratching around in the run. If it was my house, I suppose the proper thing to do would have been to get a backhoe and get rid of all that soil somehow, or drop a 6 inch slab of concrete over the area. However, that run is about 12'x15', which turned out to be way too expensive for me, and nevermind the logistics of moving the hens and coop somewhere else for a few days!
What I ended up doing (and what the vet agreed would be a decent idea) was buying a bunch of tarps to provide a barrier between the leaded soil and then buying enough new topsoil to give about a 6'' layer on top. In theory, the hens would eventually recover. I could have chelated them all, but the vet wanted an absurd amount of money (approx $150 per hen!). I decided to just let this run its course and see what happened in the future.
About a week after I got all that soil in 3 of the remaining 5 hens started laying! Fearing that the eggs would be lead infested, I took them to work to run a similar test. Apparently lead tends to accumulate in the yolks, so I separated those and analyzed them. We couldn't detect any lead at all. Good news finally!
So its been about a month and a half now and everything seems pretty good. Two of my hens (a buff orpington and a black star) still haven't started laying, but I figured they would just need more time. The other 3 have been laying somewhat sporadically but I also chalked that up to being young and possibly still suffering some lingering lead poisoning damage.
Unfortunately, over the past week or so I've noticed my Buff acting a bit...strange. She's been limping around for a few days now and seems content to just sit down either in the coop or just on the ground. She seems to be favoring her left leg as much as possible. She'll limp over to me when I go out in the morning to put some food and water out but otherwise goes right back to those spots. I'm not sure what she did to injure her leg as it seemed to pop up overnight. She's still able to get up to her roosting bar and move around but just really slowly. Think this is something I should be concerned about? I'd take her to the vet but I'm a little cash strapped at the moment. The last set of vet visits to figure out the lead poisoning cost me a couple hundred bucks =(.
A few other things I've noticed about her:
She seems to be much heavier than the other hens.
She's not laying.
She'll occasionally "yawn" over and over for 5-10 minutes while she's laying there. Yawn might be the wrong word, but it almost looks like she's trying to crow but just not making any noise.
Think all of this could be related to the lead poisoning? Or is it possible that something else might be going on? I'm wondering if she has some sort of fluid buildup or something of the like that's making her seem heavy. I haven't noticed and blood or heavily liquid poop coming from her. Do chickens have a "in pain" stance or face? She still clucks at me and eats out of my hand, so it doesn't seem like she's miserable.
The others seem fine I guess. The Easter Egger, Wyandotte, and Maran seem to be laying sporadically, while the Black Star hasn't laid at all. I'm sure they're gonna be screwed up for awhile. Maybe they'll get more consistent in the spring?
Thanks in advance for any comments or tips y'all might have.
TL;DR version: I have chickens recovering from lead poisoning. Should I put them all down and get new ones in the spring? Or see if these recover?