In eastern Canada and I think to some extent in western Canada as well, marketing of one pig is a challenge and so a farm that is able to produce pigs without the use of antibiotics in theory could have a marketing advantage over a farm that is unable to do that and that could be desirable.
More generally I think it's important for probably every farm, whether their mode of production is conventional or some form of antibiotic-free, I think it's important to be asking ourselves the question, "what is the minimum amount of antibiotics we need to keep the pigs healthy, protect the welfare of the pig and protect food safety without going overboard and using more than we have to and incurring the added cost of that, not to mention the added risk of creating antimicrobial resistance.
Dr. Wideman suggests health is king so a farm that's free or could be made free of diseases that drive antibiotic use is number one.
Source : Farmscape.ca