Such medications, classified as veterinary antibiotics, are often used by pet owners to treat bacterial infections in fish and livestock. For those preparing for a breakdown of emergency services in the event of widespread disaster where hospitals may be closed down and medical personnel unavailable, the banning of these drugs means that preppers can no longer purchase these medications over the counter and outside of view of prying surveillance state eyes.

Starting January 1, 2017, the equivalent of a veterinary prescription will be required for certain OTC antibiotics.

James Rawles reports via Survival Blog:

Many preppers store antibiotics for fish or livestock water/feed medications over the counter (OTC). As of January 1st, 2017 this will come to an end as livestock producers will be required to get a VFD (veterinary feed directive) from a veterinarian to obtain these antibiotics. I don't want to go into the specific differences but think of it as a prescription.

For anyone  wanting antibiotics I would recommend getting some before the first of the year.
I am a mixed animal vet in  the Ozarks. –  E.E.