Meat and milk from cloned cattle are virtually identical to the same products from prize animals bred the old-fashioned way, researchers in Japan and the United States reported on Tuesday.

While cautioning that their study is not the definitive report on whether it is safe to eat cloned animals, the researchers said it suggested they might be.

Xiangzhong Yang of the University of Connecticut and colleagues at the National Institute of Agrobiological Science and National Institute of Animal Health in Kagoshima, Japan, cloned beef and dairy cattle and examined their meat and milk.

They compared the meat and milk from the clones to that of animals of similar age, breed and genetics bred naturally.

“We found no significant differences in the composition of milk from cloned animals compared with the comparator animals managed under the same conditions,” the researchers wrote in their report, to be published this week in the Proceedings of the National Academy of Sciences.

The differences found in meat related to levels of fat and fatty acids and muscle qualities.

Their analysis also suggested that the clones were healthy and normal based on examination of their chromosomes, which carry the genes, as well as development and behavior.

In 2002 a National Academy of Sciences panel said it appeared that products from cloned animals were safe to eat but noted there had been very few studies. The U.S. Food and Drug Administration is expected to issue its initial guidance on the safety of cloned animals products soon.

The FDA’s Center for Veterinary Medicine has asked companies not to allow clones, their offspring, or their milk, meat or other products to enter either the human or animal food supply in the meantime.

The idea behind cloning livestock is to create herds of standardized prize animals that then could be bred more conventionally. Animals are also cloned for medical use; for instance, to produce human therapeutic proteins in their milk.

But cloned animals often appear abnormal and can die at or just after birth. There is some evidence that the cloning process itself can activate genes that should not be active and no one knows what the effects of that may be.

It may be a technical issue - cloning is tricky and some labs are better at it than others. Yang’s team set out to see if it was cloning itself that caused the problems.

They analyzed the protein, fat, and other variables routinely assessed by the dairy and meat industries and found no significant differences.

There were 12 differences seen in meat - eight of them showed higher levels of fat and fatty acids, which are valued in Japanese beef cattle and within industry standards, the researchers said.

“The fact that both clones had consistently higher amounts of mesentery fat and fatty acids compared with the comparators is hardly surprising because these two clones are genetic copies of a top breeding bull and they both exhibited the most preferable values as expected,” Yang’s team wrote.

The other four had to do with muscle qualities and also were within standards, they said.