Dr. Doherr also recommends more stringent regulations for meat that is mechanically stripped from carcasses in processing plants. A small test conducted by the Agriculture Department in 1997 showed that of the 13 samples of meat stripped by machinery, two contained spinal cord tissue. The meat stripped mechanically is used in hamburgers, hot dogs and other sausage products. As a result, the department began requiring processors to remove the spinal cord before putting the carcass in the machine, and it said it would randomly inspect the meat for traces of nervous system tissue. Ms. DeWaal said the United States should adopt European-style rules banning the spinal column that encases the cord from use in mechanical meat recovery systems.
Cattle feed can also be hazardous.
Regulatory authority over animal feed rests with the Food and Drug Administration. In 1997 the agency outlawed the feeding of meat and bone meal from mammals to cattle and sheep. But chickens, pigs and farm-raised fish are still given feed made from slaughterhouse waste. When those animals are slaughtered, their waste is, in turn, fed to cattle and sheep. Also, the F.D.A. recently reported that more than 20 percent of the companies inspected over the last three years were either keeping inadequate records, not labeling their products to distinguish feed containing mammal products from others or had no method to prevent waste from cows and sheep from being mixed with waste of chickens or fish.