On Thursday, two European agriculture feed manufacturers announced a new line of chicken feed they've been developing laced with probiotics to help farmers curb or cut their use of antibiotics. The probiotics work by keeping the birds' gut microbiota healthy, enabling them to fight off bad bacteria, and break down their food more efficiently so they grow nice and big, according to Carmen Cordova, a staff scientist with the Natural Resources Defense Council.

"A chicken is produced in a fairly clean and sterile environment because you want to keep out bad bacteria," Cordova explained in a phone interview. "The problem with that is you're also keeping out good bacteria. We know that having good bacteria in your gut can actually keep you healthier: you aren't as likely to get sick if bad bacteria does get in. So the probiotic is a way to feed that good bacteria into the chicken's gut."

Right now, antibiotics are widely used in farming both to prevent disease and promote growth in animals. But the problem is that overuse can contribute to the development of antibiotic-resistant superbugs, which sometimes make their way to humans and can cause untreatable infection.