WASHINGTON — Super Chicken strutted a step closer to the dinner table Thursday.

The government said it will start considering proposals to sell genetically engineered animals as food, a move that could lead to faster-growing fish, cattle that can resist mad cow disease or perhaps heart-healthier eggs laid by a new breed of chickens.

The rules will also apply to drugs and other medical materials from genetically engineered animals, a field with explosive potential.

U.S. supermarkets currently sell no meat from genetically engineered animals. But a Boston-area company called Aqua Bounty Technologies hopes to win approval next year for its faster-growing salmon and make the fish available by 2011. "It tastes just like any other farm-raised salmon," said vice chairman Elliot Entis.

Reaction from consumer groups was mixed. They welcomed the government's decision to regulate genetically altered animals, but they cautioned that crucial details remain to be spelled out. For example, the Food and Drug Administration does not plan to require that all genetically engineered meat, poultry and fish be labeled as such. It would be labeled only if there was a change in the final product, such as low-cholesterol filet mignon.

"They are talking about pigs that are going to have mouse genes in them, and this is not going to be labeled?" said Jean Halloran, director of food policy for Consumers Union. "We are close to speechless on this." Consumers Union publishes Consumer Reports magazine.

Nonetheless, Gregory Jaffe, who heads the biotechnology project at the Center for Science in the Public Interest called the FDA's move a "good first step."

"This is the first time the federal government is announcing a comprehensive regulatory system that addresses the concerns from these animals," Jaffe said. "But it may not have addressed all the environmental concerns."

What would happen if a genetically engineered animal escaped and started reproducing with wild animals of the same species? asked Jaffe. The FDA said it would address that issue.

On Thursday, the FDA released a proposed legal framework for how it would resolve such questions as whether the altered animals are safe for human consumption and whether they pose any serious environmental risk. FDA officials said they were focusing on animals that will be used as food, or to produce medications to be consumed by people or by other animals.

Genetic engineering is already widely used in agriculture to produce higher-yielding or disease-resistant crops. But it's unclear how consumers will react to altered animals, even if they come with a government seal of approval.

Genetically engineered animals are manipulated by scientists to bring about a change in their characteristics. In years past, this was done by crossbreeding animals with desirable traits.