I gave 1/2 a cc of tylan 50 for 5 days and she has been off of it for about 5 days. Although it looks better, it still isn't better. I also have some Corid and some Duramycin. Should I give her another round of Tylan or try one of these others? If so, how long and what dose? Aside from this horrible thing on her face, she is happy as a clam, eating and drinking fine.