What's interesting is that a big driver for this is social media. I was at a conference once & the CEO of Perdue listed this as a top driver behind this movement. He justified it this way: imagine that it costs an extra $0.01 per pound to create chicken meat that is antibiotic free. If the profit margin was $0.05 per pound that would cut profits by 20%. Today, negative PR on Facebook or Twitter can quickly spread to erode the value of a brand far more than $0.01 per pound of cost savings. He said that the reason for the switch is driven by consumers, who are now empowered by social media.

From a nutrition tech standpoint there are a number of products including probiotics, beta glucans & others that help to protect the birds by boosting immune system activity rather than by killing bacteria. When used in combination with vaccines they can be very effective, albeit slightly more expensive. However, these ingredients add cost & come at a metabolic cost to the animal (i.e. it takes more food to produce 1 pound of meat if more of that energy is directed towards a functioning immune system & away from weight gain).

Animal nutrition science is in many ways more advanced than human nutrition due to the ability to conduct controlled studies and access to large amounts of data. However, the goals are very different.

Animals account for ~80% of antibiotic usage in the U.S. and MRSA now kills more people in the U.S. than HIV. It's an interesting topic.