Prominent owner Zayat Stables has directed the scratching of all of the stable's horses entered for this weekend's races under the name of trainer Steve Asmussen.
The action by Zayat is the first major fallout from a New York Times article published Thursday and based on a 2013 undercover investigation by People for the Ethical Treatment of Animals within the Asmussen operation.
In a tweet, Zayat Stable's Justin Zayat said the action to scratch the horses was "pending further investigation from our side with these matters."
Ahmed Zayat said in a text message that he was traveling early Friday morning and would issue a statement later in the day.
According to Equibase, Zayat had entered two horses trained by Asmussen -- Skinny in the second race at Fair Grounds Racing & Slots and Selway in the second at Oaklawn Park, both Sunday.
Hall of Fame trainer D. Wayne Lukas has two Zayat-owned horses entered Saturday at Oaklawn -- Gridlock in the seventh and Brewing in the featured Gazebo Stakes.
The Jockey Information Systems shows Zayat and Asmussen have teamed for at least nine stakes races since 2007, including with Grade 1 winner Justin Phillip and Grade 2 winners J Be K, Prayer for Relief, and Soul Warrior.
Information reported by PETA and included in the Times story alleges overmedication of and cruelty to horses, as well as use of electrical devices on them.
The newspaper said it wrote the story on the condition it not publish the name of the investigator, who is said to have worked for Asmussen and his assistant, Scott Blasi, for four months at Churchill Downs and Saratoga Race Course.
Prominently mentioned in the Times article was Zayat-owned Nehro, who was known to have hoof issues and reportedly died from colic on the way to an equine hospital the day of last year's Kentucky Derby at Churchill.
The PETA investigator also alleged Asmussen employed undocumented workers and encouraged use of false documents, according to the Times.
The National Museum of Racing and Hall of Fame announced Friday that the nomination of Asmussen for possible induction into the shrine this year has been tabled.
"It is certainly a surprise to Mr. Asmussen and Mr. Blasi that anyone would deceptively get a job and keep surveillance and their notes on their conduct for the agenda of others," Asmussen and Blasi's attorney, Clark Brewster, told the Times. "They will reserve comment with regard to any accusations until they have had the opportunity to fully review them. Then they will respond factually."