Plans to allow milk and meat from cloned cows to enter the food chain have moved a step closer in the US after the country's food safety watchdog issued draft guidance for the industry and opened a formal consultation.
Milk and meat from cloned cows, pigs and goats is as safe as that from conventionally bred herds, the Food and Drug Administration (FDA) confirmed. Sheep are excluded.
It opened a 90-day public consultation on this opinion, backed by several studies, and on how clones and their offspring could be managed and monitored in the food chain.
The consultation presents a dilemma for the US dairy industry, which will have to weigh up negative consumer attitudes against potential benefits greater use of cloning may bring. Dairy industries in Europe and beyond are also watching closely.
Consumer groups have continued to attack FDA proposals.
"Cloning will not produce safer or cheaper milk and meat," said the Consumer Federation of America (CFA), accusing the FDA of trying to force such products onto an unwilling public.
Almost two thirds of Americans said they were uncomfortable or strongly uncomfortable with animal cloning, in an independent survey last year.
The CFA also raised concerns over the health of cloned animals and their offspring, amid some evidence that animal cloning carries a higher risk of abnormalities and premature death in offspring.
Stephen Sundlof, director of the FDA's Center for Veterinary Medicine, said: "Cloning poses no unique risks to animal health when compared to other assisted reproductive technologies currently in use in U.S. agriculture."
Dairy industries must weigh up whether the potential benefits of cloning, such as breeding super-efficient herds that produce higher milk yields, make it worth tackling widespread public scepticism.
More large studies will be important to assess the effects and feasibility of using cloning technology in the dairy industry, said Xiangzhong Yang, animal cloning expert, told DairyReporter.com.
Yang led one of the main studies used by FDA officials in assessing the safety of food from cloned animals. He found no difference in milk quality, including protein, fat, antibody and lactose content, from cloned cows.
Europe's dairy industry remains cautious.
"This is a new development and something that may offer possibilities to improve milk production by cows, but there's no intention as far as I know to have this introduced into the EU in the short or medium term," Joop Kleibeuker, secretary general of the European Dairy Association, told DairyReporter.com recently.
"We don't see acceptance of this from EU citizens, and we are producing products for our consumers."