To reach niche markets,  some livestock producers are seeking opportunities to raise animals without the aid of antibiotics. 

There is no one replacement for antibiotics when it comes to animal health and growth promotion, experts said during the Iowa Pork Congress, held recently in Des Moines. But researchers continue to look for alternatives. 

“What we know from our work in this area (is) raising animals this way is more labor intensive, it’s more work and it’s more...