'The cost is incredible' says a dismayed O'Brien after missing out on Arc

Aidan O'Brien has hinted at the huge financial and emotional cost of being forced to scratch all his runners from Sunday's Prix de l'Arc de Triomphe card at Longchamp due to contaminated feed.

But the trainer revealed that he hoped to be free to have runners again as early as this Wednesday in Ireland.

O'Brien and his sons Joseph and Donnacha withdrew runners from all meetings after urine samples that were sent to a French lab returned positive for the prohibited substance Zilpaterol.

Longchamp card and betting

It followed news that Gain Equine Nutrition had advised its customers to stop using their feed products after batches had become contaminated with Zilpaterol, which is unlicensed in Europe but is used in the US and elsewhere to promote weight gain, mainly in cattle.

Aidan O'Brien had been due to have four runners in the £2.5million Arc alone, including the Derby winner Serpentine who, was supplemented for 72,000 Euro, and he expressed his sympathy for the Coolmore axis that bankrolls the Ballydoyle operation.

"I feel sorry for the lads," he said on Luck On Sunday. "They put so much in and the cost is incredible.

"Everyone's working so hard to try to breed the horses, to sell the horses, to train them, to race them, They put in so much to get the horses to this stage, they try and make it happen, I feel so sorry for them. I hope we're all able to work it out.

"This morning it is very quiet here."

Gain Equine Nutrition tweeted their sympathy for this affected and said: "The team at GAIN Equine Nutrition are hugely disappointed to learn that some of our customers have withdrawn their horses from important equine events this weekend, including the Prix de l'Arc de Triomphe in Paris.

"We are continuing to work closely with all appropriate agencies, including the Irish Department of Agriculture, to fully investigate the source, nature and extent of this contamination.

"We are also in close contact with horse racing regulatory bodies. We will provide a more detailed update once further information is available."

Looking ahead, O'Brien has entries in Ireland this week and many top two-year-olds entered in the Group 1 Fillies' Mile at Newmarket on Friday and Dewhurst Stakes there on Saturday.

"I suppose the best case scenario is we would have to have a two or three-day withdrawal stage and that maybe we could be back racing on Wednesday or Thursday," he said.

"We may have runners on Wednesday, Thursday and Friday in Ireland and hopefully runners over the weekend. We would have to do blood and urine samples from the horse probably starting tomorrow and do them every day all the way up to the weekend.

"But everyone in Ireland and England has to see are they going to do the tests, and if they do how low the bar is going to be? There's an awful lot of questions that have to be answered. We're going to start testing on Monday and we'll do it every day, probably using the French labs until there are some labs in England or Ireland that we can use."

How the drama developed:

O'Brien Arc runners among those in doubt due to contaminated feed

Aidan O'Brien and sons forced to withdraw all Longchamp runners on Sunday

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