Piglets can be terribly cute, and have about the same level of intelligence as chimpanzees. It gets noticeable when they are raised around puppies, because they can often out think them and actually teach some skills to the puppies.
They'll also be glad to eat you when they get older if you happen to wind up off your feet in their enclosure.
Grew up on a small farm, raised hogs, and myriad other animals. Pigs are very smart. Never supplemented with anti-bs, but it was very common with cattle, etc., on big farms. The use of anti-b’s in so many things even apart from food, such as soaps, just has to be a factor.