I think everyone is just trying to be helpful here, not really trying to put anyone down. Most of us are not experts on here, and there is very little medicating of chickens by vets or recommendations by the drug companies if you have been looking around online. Most of the info we have is just from backyard or old farmers who have tried various meds and got good results. If you read threads about Tylan use, the doses are all over the place. If you aren't seeing results with the Tylan you might up the dosage and see if it helps, but in a day or two I might switch to another. Some of these meds are very expensive, and if the lesser expensive ones work, that is good. It is good that there is a handbook out there on drugs, but since most of this is off-label use, I would appreciate the drug companies publishing doses more. Okay, off my soap box...