Hi while you are waiting for casportpony to respond, wanted to add the following. I read back through a lot of old threads re denagard this morn. The cc/ml dose translates to 3 teaspoons/gallon of water for treatment for 5 days. And then 1 and 1/2 teaspoons/gallon as monthy preventative for 3 days. Some people said they used denagard for as long as 7-10 days. Like ivermectin, tiamulin (denagard) has a broad safety margin. Treated water needs to be changed out daily. Also, denagard med is very bitter, so many recommend adding juice, honey or sugar to water to hide the bitter taste. You are dealing with an additional "problem" right now, which is that due to cold temps, your girls arent drinking nearly as much. Adding treated water to make a mash for them to eat will deliver more med to them. Adding treated water to delicious treats even better! And this. My very favorite pullet at the time got Very sick with classic mg respiratory symptoms. She was too sick to want to eat or drink. I took her to work with me in a dog crate for 3 days straight, and syringed water into her throat every 2 hours. After 3 days she turned the corner, and all symptoms disappeared within a week. (I never tried tylan injections on her because tylan didnt work on other pullets). But in reading through old threads this morn, one poster said denagard did NOT work as initial treatment, even though it did work as a monthly preventative, and her chickens never showed symptoms again. That poster said tylan injections were effective as initial treatment. So while waiting for denagard to arrive, u are certainly doing no harm giving tylan. Best case scenario tylan alleviates the symptoms.
Two final points. 1) Avoid giving denagard with some anti-coccidials, as a negative reaction may occur. Amprolium/tiamulin combo IS safe to give.
2) A synergistic effect has been shown to occur in studies when tiamulin was given along with tetracycline. Azygous, you may have already read and researched all the above info (and more), but above info may hopefully help those in future who discover this thread.