The U.S. Farmers and Ranchers Alliance shared a news item recently that demonstrated what can happen when antibiotics aren't used to treat sick animals:
"A study researching how porcine reprodcutive and respiratory syndrome (PRRS)-challenged pigs performed in swine production systems that don't use antibiotics was stopped because "the animals in the antibiotic-free group were sick but could not be treated with antibiotics," PVS Research Director Scott Dee said.
"The pigs were really suffering. We were seeing high mortality levels; pigs were huddling and had a lot of weight loss. We had to stop the study and treat (anitibotic-free) pigs for welfare reasons."
Read more information about pig farming myths on the Food Dialogues website here: What You Need To Know About Pork