Although the FDA seems to have backed off, farmers and brewers are still nervous about the FDA's rule, which will be proposed again at the end of summer. Shelly Pope/KQED hide caption

itoggle caption Shelly Pope/KQED

Fox Ranch, outside Yuma County, Colo., is a 14,000-acre nature preserve and working cattle ranch owned by The Nature Conservancy. The ranch is an experiment in planned grazing, which aims to improve soil health and help ranchers' bottom lines. Luke Runyon/Harvest Public Media hide caption

itoggle caption Luke Runyon/Harvest Public Media

Rancher Denny Johnson looks over his cattle in Joseph, Ore., in 2011. Conservationists say ranchers raising beef cattle are responsible for the decline of some wildlife. Rick Bowmer/AP hide caption

itoggle caption Rick Bowmer/AP

Young broilers nibble feed at a chicken farm in Luling, Texas. The Food and Drug Administration has issued new guidance on how drug companies label antibiotics for livestock. Bob Nichols/USDA/Flickr hide caption

itoggle caption Bob Nichols/USDA/Flickr

Russ Kremer with some of his hogs on his farm in Frankenstein, Mo., in 2009. Instead of buying conventional feed, Kremer grazes his hogs in a pasture, and grows grains and legumes for them. Jeff Roberson /AP hide caption

itoggle caption Jeff Roberson /AP

A truckload of live turkeys arrives at a Cargill plant in Springdale, Ark., in 2011. Most turkeys in the U.S. are regularly given low doses of antibiotics. Danny Johnston/AP hide caption

itoggle caption Danny Johnston/AP

Cows wait to be milked at a California dairy farm. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images

The FDA's latest effort to end the use of antibiotics as growth promoters in animals is getting mixed reviews from activists. Rob Carr/AP hide caption

itoggle caption Rob Carr/AP

Pigs take a mud bath at the De Jofrahoeve pig farm in Esch, Netherlands. Dutch farmers treat their animals with almost three times the antibiotics that their Danish neighbors use. Robin Utrecht/AFP/Getty Images hide caption

itoggle caption Robin Utrecht/AFP/Getty Images