I tried to edit my thread above which failed. I looked up an older post of Casportpony's where she weighed the Duramycin10 on a gram scale (of course she did--she always does, LOL!) and the 800 mg dose is 1.5 TB. Some older posts recommend 3 tsp or 1 TB.I would trust the 1.5 TB per gallon dose...
I have an old bag of Duramycin 10 (tetracycline.) It is mixed 1 TB (for 400mg) and 2 TB (for the 800mg dose) in a gallon of water. You can give it 7 days but no longer than 14. Of course, I would use the higher dose for anything.
Well I was wrong. I just looked again, and it doesn't say...
Many hens would drink closer to a quart in a day, and that would be just less than teaspoonful. I would probably just round it off to a teaspoonful, and not worry about it.
This is off the Durvet Brochure for Duramycin10:
Duramycin 10
(tetracycline HCl soluble powder)
For use in drinking water for prevention and treatment
of diseases susceptible to tetracycline hydrochloride.
• Contains broad spectrum anti-bacterial action of
tetracycline hydrochloride.
•...