DES MOINES, Iowa — A father and son whose Iowa-based egg production company caused a massive 2010 salmonella outbreak have exhausted their appeals, and a federal judge has ordered them to begin serving prison sentences.

The US Supreme Court declined in May to hear the appeals of Austin ‘‘Jack’’ DeCoster and his son, Peter DeCoster, without comment. Both have been sentenced by US District Judge Mark Bennett to serve three months in prison. The sentences jarred the food and drug manufacturing industry because it’s rare that corporate officials are held personally responsible for an outbreak of foodborne illness.

Business groups — including the National Association of Manufacturers, the Pharmaceutical Research and Manufacturers of America, and the libertarian Cato Institute think tank — filed friend-of-the-court briefs backing the DeCosters’ appeal. The groups argued that it is unfair to send corporate executives to prison for violations that they were either unaware of or that were committed by subordinates.

Bennett in his sentencing opinion filed in April 2015 concluded that prison time was necessary to deter officials from marketing unsafe food.

ASSOCIATED PRESS