In his decision judicial committee chairman Murray McKechnie said the offending was serious and unsatisfactory explanations were given by McDonald and Donaldson.
"For its part the committee believes that a clear signal must be sent to the industry making it plain that breaches of the prohibited-substance rules will be met with a significant consequence.
"Phenylbutazone was administered to four horses in breach of the rule.
"The explanations of how the administration of phenylbutazone came to take place were unconvincing. There were multiple breachings of the prohibited-drug rule.
"The committee considers the offending to be serious."
Donaldson told the hearing she had administered the bute at 4.30am before the horses left Cambridge for the trials.
She said she frequently administered the drug at the direction of McDonald and knew it had a 10-day withholding period. However, she was insistent this time that McDonald had no idea she gave the drug, evidence which could not be reconciled with what the trainer said himself.
Costs were awarded against both with the JCA to receive $3000 and the RIU $2500 from each party. The disqualifications will begin on May 1 to allow horses in their care to be relocated. NZ Racing Desk