The Penicillin is for secondary infections that might occur in his weakend immune state, like Pnuemonia and as for Albon , I am no Vet by any means but I do think I read, when boning up on this Coccidiosis thing, that is was treated with Sulfa drugs. Perhaps I misread, but I have been trying to learn all I can and been pouring over material in the process, maybe I should review what I thought I learned. Too, I'm still beating my brains out on how he got it since it primarily is a bird disease. I have Muscovy Ducks wandering about and the Cow Birds are thick too.
I can only assume that he ate some grass that had infected dropping on it.
None of my other cows show any signs.
He just got lucky, I guess.