DES MOINES, Iowa — Nearly a year after nations banned U.S. pork over fears about swine flu, China has become the last one to lift its embargo and is expected to accept shipments by early next month.

It's a move welcomed by an industry that has suffered several years of losses, but some experts caution farmers shouldn't expect to see a surge in exports. China still produces most of the pork it consumes and won't accept pork containing ractopamin, an additive used in the U.S. that causes hogs to turn feed to muscle instead of fat.

Still, lifting of the ban is good news for U.S. pork farmers, who were hit with a triple whammy of high feed costs, a drop in demand at home with the recession and import bans by more than two dozen countries worried about transmission of swine flu, also known as H1N1.

Before the bans, about 20 percent of U.S. pork was exported, and China and Russia were among the biggest buyers.