I have some hens who are gurgling and sneezing. Still eating well and active. Vet checked them out and didn't know what it was but nobody has gotten worse in a week. Just keep gurgling and sneezing. I'd like to give them some deramycin in their water and see if I can clear them up a little. Unfortunately, I have 8 hens and the package makes 12.5 gallons of water. Thoughts on how much to give? I think it works out to 1/8 oz per 32 ounces but wanted to ask the experts.