Six of the largest school systems in the U.S. announced plans to serve students chicken raised without antibiotics in school cafeterias.

Coordinating as the Urban School Food Alliance, the schools represent nearly 3 million students and include New York City, Los Angeles, Chicago, Dallas, Miami-Dade County and Orlando County.

The new policy mandates that all chicken is raised on a vegetarian diet, never fed animal by-products, humanely raised and never given antibiotics.

“The passing of the resolution shows the bold steps school districts are taking to ensure the health and wellness of students,” said LAUSD Deputy Food Services Director Laura Benavidez.  “Providing the best possible, highest quality food for students shouldn’t be a privilege, it should be a standard.”

Switching to the new policy may take several years in order to allow meat suppliers and producers, including Tyson, Pilgrims Pride and Perdue, to comply with the new standards.

“This is a critical piece of ensuring the safety of our children,” said Mark Izeman, Senior Attorney with the Natural Resources Defense Council (NRDC), who helped develop the new plan. “Today’s transformational move will not only have a dramatic impact on the quality of school meals, but will also help push the entire food industry to move away from animals raised with improper antibiotic use.”