A catfish by any other name would taste as good?

The catfish is the latest Asian import to threaten the USA-produced version.

If Vietnamese growers can be believed, tra may be the most efficient way on earth to make animal protein. It takes three acres of grazing land to grow a single 700-pound cow. That same land, flooded and turned over to channel catfish ponds will generate 25,000 pounds of catfish. But in Vietnam, those three acres will bring in up to 1 million pounds of tra. The question that fish farmers outside of Southeast Asia ask is whether the Vietnamese are competing on a level playing field. And if not, they wonder, are the Vietnamese grabbing up huge swaths of the global white-fish market at the expense of environmental and consumer safety?

Under pressure from the Chinese, the Vietnamese are even trying to cross the tra with the giant Mekong catfish, which grows up to ten feet long and can weigh 1000 pounds.

• food
• Vietnam