NASHVILLE (AP) - A Tennessee walking horse group that is suing the U.S. Agriculture Department over new rules to stop soring says it has received notice of decertification from the USDA.

The SHOW Horse Industry Organization needs the certification to perform inspections at horse shows. It received the notice after failing to meet a July deadline to adopt tougher inspection rules.

Soring is the practice of causing injuries to a horse's legs or hooves to exaggerate the high-stepping gait that wins prizes at horse shows.

The decertification process is not complete, and SHOW said in a news release on Tuesday that it will have inspectors at the Tennessee Walking Horse National Celebration later this month in Shelbyville.

USDA spokesman Dave Sacks said he could not comment on SHOW because of the lawsuit.