The U.S. Agriculture Department plans to start testing for salmonella bacteria in plants that process turkeys.

The Agriculture Department for years has been doing similar carcass testing in plants that slaughter hogs, cattle and chickens.

The testing in turkey plants is due to start in May or June. It’s part of a broader plan to reduce the number of salmonella infections, which have been rising even as illnesses from other types of food-borne germs, such as E. coli, campylobacter and listeria, have been declining.

"Turkey plants have to be tested like everybody else," said Caroline Smith DeWaal of the Center for Science in the Public Interest, an advocacy group that has been critical of the industry’s uneven sanitation record. "The range in turkey processors between those that are really controlling salmonella and those that aren’t is huge."

In addition to the new testing program for turkey plants, the Agriculture Department’s anti-salmonella plan calls for informing processors of testing data more quickly and stepped-up scrutiny of plants that have problems.