Sheikh Mohammed's Dubai Millennium, who has been diagnosed with an acute case of equine grass sickness, remains in stable condition at a Newmarket clinic. The 5-year-old stallion was sent there Monday, April 21, from Sheikh Mohammed's Dalham Hall Stud near Newmarket and underwent surgery that day and the following day because of complications."On Monday morning, Dubai Millennium covered a mare," said Sheikh Mohammed's bloodstock advisor John Ferguson in a prepared statement. "He appeared in great shape, perfect in every way. After lunch, Liam O'Rourke (Dalham Hall stud director) came to me as he suspected a case of colic. Vets Huw Neal and James Crowhurst agreed with Liam, and Dubai Millennium was rushed into Greenwood, Ellis, and Partners in Newmarket."The decision was made to operate immediately and an impaction was found in the small intestine. Dubai Millennium came round well from the anaesthetic and was in good shape."He was fairly sprightly on Tuesday morning, but by 11 a.m., the vets had become increasingly worried as there was no action from the intestine. I spoke with Sheikh Mohammed again on Tuesday. The message was that we had to operate again."After the second operation, no further impaction was found. A biopsy was taken and rushed to the Animal Health Trust for analysis. It came back positive for grass sickness."Sheikh Mohammed flew in on Wednesday morning and our team of experts continued to try and find a solution to this very serious problem."Grass sickness is believed to be caused by a toxin picked up from grass, which then attacks the nervous system of the intestine. Not a great deal is known about it, and Dubai Millennium has an acute case. Everything is being done to solve what is a very, very serious problem."The key is to keep Dubai Millennium stable. If we can keep him in a stable condition and eliminate all the toxins, we hope the healthy nerves can then start to compensate for the ones that have died. If the horse is no longer stable and is suffering, then we'll have to do the right thing by him."Dubai Millennium (Seeking the Gold--Colorado Dancer, by Shareef Dancer) won nine of 10 races and earned $4.4 million. He began his stallion career this year for a reported £100,000 (about $150,000).