Tim there used to be a product a product called Odor Mute that you could find at Nite Lite or Bill Boatman hunting supplies that would help. I used it years ago when I had my racoon dogs on dirt. Mine have been on concrete for years now. I spray the kennels with Clorox in a pump up sprayer and that helps sanitize and I don't really notice the smell at all this time of year. This rainy wet weather hasn't help your situation much. Slack Lime ( White Lime) helps too but I think it would be more for flies than smell.
I would be glad to come take another one or two off your hands too if that would help. lol
You can go to sams and pick up a product called "Odo-Ban". I mix it in a bug sprayer... every weekend when I clean old straw and such I spray the floors... edges of kennel boxes.... along the fence rail. It is what a lot of vets use in their kennels... It is an anti bacterial spray so it will kill germs and such as well.
Southern States sells a product called Creolin mix a couple of cap fulls and some water in a pump up sprayer and spray it around the kennels it works good, when it rains the water helps bring the smell back out, just bought a bottle yesterday at 13 dollars a bottle it lasts a long time
I keep my grown dogs on concrete but the pups are out back in above ground pens.I sprinkle lime over the poo weekly and spray it at the same time.I use pine-sol mixed with some water and spray around the pen and on top of the lime to help the smell.In the summer time and after it rains the humidity gets up and the smell is worse than usual.I also use the pine-sol on the concrete floor for cleaning.
I Will Second the Odo-Ban Stuff works great.. I have Concrete with a Septic System But it is not completly finished yet so when i wash down some gets into the dirt around the edge I use the odo-ban and it seems top work great..We also use it to Sanitize the whelping area gets rid of most any bugs....
Use hydrated lime or hot lime not the garden lime.It will knock the smell out but will have to re apply after rain.It will also help kill flea eggs,have used it for 20 years and you can get a 50 lb bag.good luck!!
I sprayed mine down with bleech and water to kill coccidia. Then let it soak in for a day or two. Then soaked it with just water. (Dirt floors by the way.) Then I let it dry out a couple of days before I put any dogs back in. Can't smell anything now.