Hi, John; so sorry to hear your little ones are still battling the sneezing. Sigh. (Got your PM, too).
You mentioned using lime and the DL method; I could be wrong, but I feel like I've read on here that you should NOT use lime...I wonder if that could be part of the issue? I've tried the DL method and I just cannot seem to make it work for me. Each time I try, my coop ends up smelling poopy and of ammonia, so I've returned to thoroughly cleaning/removing all litter and replacing it.
You've probably already got the Tylan injectable; if so, please do use it and keep us posted. But, I also wanted to throw this out to you - I've got a friend whose been into chicken and other poultry for many, many years. I've been corresponding with her regarding a pullet I have that's been battling some sort of respiratory thing for weeks now, and here is her recommendation when I told her how frustrated I am, and that I don't know what to do next:
"Spectam injectable is great if you arent afraid to give bird a shot. It is
really easy to do. I keep a bottle on hand, and have saved some pretty sick
birds with it. I learned about it from a very experience dairy farmer who
also knows a lot about poultry:
"Give a shot of Spectam every 24 hours for 5 to 7 days at the rate
of 1/10th of a cc/ml per pound of body weight. So, a 5 pound bird would get
1/2 cc/ml. Just inject the bird in the breast meat deep enough that the
medicine doesn't come back out. This Spectinomycin seems to work pretty
good on CRD and Coryza. It's made to be used on Turkey Poults. We started
using it years ago when one of the Vets up here that was a Poultry Fancier
put us onto it. It beats Tylan 200 and Gallimycin for getting birds healthy
fast."
I'm going to be purchasing Spectam (my friend gets it from Jeffers.
http://www.jefferslivestock.com/ssc/ )
She also included these instructions, which would be the same for any injectable, I'd assume:
Also order or buy needles and syringes at the feed store. The bigger the
gauge, the smaller the needle so a 25 gauge needle is finer than a 20
gauge. Get the smallest needles you can find.
Get everything you need ready before you get the bird:
Rubbing alcohol
2 Cotton balls
Needle
Medicine
Fill syringe daub alcohol soaked cotton on top of bottle. Draw up a bit
more medicine than you need. Hold syringe with needle pointing up and tap
until all air bubbles come to the top. Depress plunger until air is expelled
and a stream of liquid squirts out.
Soak another cotton ball with alcohol and get the bird. Hold her in the
crook of left arm (if right handed). Find meaty part of breast and daub
alcohol where you will give injection. Stick needle in just far enough so
liquid goes in. You dont have to go deep. Depress plunger and withdraw
needle. Thats it.
You can practice on an orange.
Good luck, and please do keep us posted!!