LOS ANGELES (Kyodo) While restaurants in Japan serving "gyudon" beef on rice have been hit by the ban on U.S. beef, their counterparts in the United States are seeing increased sales despite the first case of mad cow disease in the U.S. in December.

"There is no negative effect from the discovery of the first BSE case," said Oliver Cortes, vice president of operations at Yoshinoya West Inc., which has more than 80 outlets in the U.S.

Cortes said sales at Yoshinoya West, an affiliate of Yoshinoya D&C Co., Japan's biggest gyudon chain, rose almost 4 percent in January from a year earlier.