I had the same question earlier this evening. I kept searching under "penicillin doasge" and found this post. This should answer your questions.
Bottle question: The bottle should have a rubber stopper. There is not a cap that comes off. Make sure you shake the contents of the bottle...
I have a RIR breeding rooster that has an injury to his leg and thigh due to the leg band. I just noticed the injury today and removed the leg band. I have over 100 birds that are free ranged and noticed the rooster, Bob, was "skipping" (limping) as the kids put it. Upon further examination...