Gov. Terry Branstad joined a lawsuit with five other states opposing California’s egg-production law, which discriminates against Iowa’s egg producers.

A California law requires eggs imported into the state must come from chickens raised under the state’s animal-welfare rules.

The lawsuit argues the egg-production law violates the interstate commercial clause of the U.S. Constitution.

Iowa is the leading producer of eggs in the nation, producing more than 14.4 billion eggs per year. Iowa farmers sell roughly 9 percent of Iowa’s egg production to California.

Branstad said in a press release the state of California’s “hurts Iowa agriculture and is detrimental to Iowa egg producers.”

The lawsuit was filed by the Missouri Attorney General Chris Koster and co-signed by Nebraska, Oklahoma, Alabama and Kentucky officials.

— by Stacey Murray