Tests following Silva's second-round stoppage of Eilers in Stockton, Calif., revealed the presence of the banned substance used primarily in horses.
Silva, a 6-foot-4 former super heavyweight who recently dropped down in weight to the 265-pound limit, has endured his share of medical issues. In 2007, the CSAC declined to license Silva because of concerns stemming from a benign tumor located near his pituitary gland. A year later, the 28-year-old American Top Team heavyweight was granted a license to fight.
Silva and his manager, Alex Davis, vehemently deny any wrongdoing by the fighter and intend to appeal the CSAC's findings.
"It's not our intention to go to war with the commission, but we believe they've made an error here and we're going to do our best to prove that," Davis said. "[Silva] is very, very, very strong in his opinion about these kinds of products. Besides not being able to use any of them because of his acromegaly, he is a guy of very high principles. He doesn't believe in cheating. He doesn't believe in this kind of stuff."
CSAC executive officer Armando Garcia also confirmed to SI.com that Edwin Dewees, who fought up in weight at 205 pounds at against Antonio Rogerio Nogueira at Affliction: Banned on July 19, tested positive for nandrolone. A short-notice replacement for Vernon White, Dewees, 26, lost in the opening round to Nogueira.
According to Garcia, Dewees had nine times as much of the banned substance in his system than that of Royce Gracie, who registered an "off the charts" sample of close to 70 ng/ml last year. By comparison, former UFC lightweight champion Sean Sherk was deemed positive by the CSAC after testing at 12 ng/ml following a bout in Sacramento 13 months ago.
Both Silva (11-1) and Dewees (35-13, 1 NC) were handed one-year suspensions and fines of $2,500 by the CSAC. Neither fighter has previously tested positive for banned substances.
Because of a backlog at the commission-hired testing facilities, the CSAC was forced to wait several weeks before follow-up analysis on "B" Samples could be revealed.
Quest Diagnostics and a World Anti-Doping Association facility in Montreal, Quebec, delivered the official results on Wednesday.