GRAND ISLAND, Neb.  Like many workers at the meatpacking plant here, Raul A. Garcia, a Mexican-American, has watched with some discomfort as hundreds of Somali immigrants have moved to town in the past couple of years, many of them to fill jobs once held by Latino workers taken away in immigration raids.

Mr. Garcia has been particularly troubled by the Somalis’ demand that they be allowed special breaks for prayers that are obligatory for devout Muslims. The breaks, he said, would inconvenience everyone else.

“The Latino is very humble,” said Mr. Garcia, 73, who has worked at the plant, owned by JBS U.S.A. Inc., since 1994. “But they are arrogant,” he said of the Somali workers. “They act like the United States owes them.”

Mr. Garcia was among more than 1,000 Latino and other workers who protested a decision last month by the plant’s management to cut their work day  and their pay  by 15 minutes to give scores of Somali workers time for evening prayers.