Dispute, an Ogden Mills Phipps homebred who won the 1993 Kentucky Oaks, was humanely euthanized on April 24 at Pattons Creek Farm near Goshen, Ky., due to the effects of a neurological issue. The Danzig mare was 23.

Dispute won or placed in 17 of 19 starts over three racing seasons and earned more than $1.1 million for Phipps and trainer Shug McGaughey. In addition to her Oaks victory, in which she defeated 1992 champion juvenile filly Eliza by 1 1/4 lengths, Dispute won the Grade 1 Beldame and Gazelle in 1993 and the Grade 1 Spinster in 1994.

When Giant’s Causeway was retired to Coolmore’s Irish division for the 2001 breeding season, he immediately became one of the most sought-after young sires of his era due to his excellent pedigree and his even-better ability as a racehorse.

The Kentucky-bred son of Storm Cat out of Grade 3 winner Mariah’s Storm had proven to be competitive at the highest level after relocating to Europe for the bulk of his racing career, taking on all comers at distances ranging from six furlongs to about 1 5/16 miles.

The month of April has been a productive one for the broodmare Lisa Danielle.

Last spring, owner-breeder Terry Lovingier faced a pivotal decision with Willa B Awesome, the winner of the 2012 Santa Anita Oaks.

Lovingier and his partners debated whether to run Willa B Awesome in the prestigious Kentucky Oaks at Churchill Downs or take a slightly unconventional approach with a Grade 1 winner and stay in California for the $300,000 Melair Stakes for state-breds at Betfair Hollywood Park.

In a decision based on economics and competition, they opted to keep the filly at home and watched her record her fourth and final career stakes win.

Montbrook, a Grade 3 winner and a successful Florida-based sire who was pensioned earlier this month, was humanely euthanized on April 12 at J. Michael O’Farrell, Jr.’s Ocala Stud in Ocala, Fla., due to declining health. The Buckaroo horse was 23.

Montbrook was the state’s leading sire in 2002, 2003, 2008, and 2009. The stallion, who was born, raised, and stood his entire career at Ocala Stud, was pensioned after only getting one mare in foal from 12 bred earlier this breeding season.

Group 1 winner Art Connoisseur was represented by his first winner April 23, when Der Blaue Reiter won his career debut at Great Yarmouth Racecourse in England.

Trained by George Baker for owner Clive Washbourne, Der Blaue Reiter covered five furlongs on turf rated good in 1:03.16. The Irish-bred chestnut colt is the ninth winner from 12 starters out of the Secreto mare Kafayef.

Top racemare and broodmare Air Groove, the 1997 Horse of the Year in Japan who went on to produce two Group 1 winners, died after giving birth to a King Kamehameha colt at Northern Farm on the island of Hokkaido, Japan April 23. The Tony Bin mare was 20.

"She was the most successful horse in my farm, both in her racing and breeding careers," Northern Farm's Katsumi Yoshida told the Racing Post. "She had always been at the center of the Northern Farm history. I want to say thanks again to her many fans who cheered her on."

Belmont Stakes winner Colonial Affair, who helped jockey Julie Krone make history in the classic, died in his stall the morning of April 23 at Haras El Paraiso in Capitan Sarmiento, Argentina, where he had stood for the last decade. The Pleasant Colony horse was 23.

Storm Cat, the prominent American stallion who sired champions on both sides of the Atlantic and inspired multi-million-dollar bidding wars for his foals, died Wednesday at age 30.

With both Thoroughbred racetracks in south Florida scheduled to begin hosting competing year-round race meets this summer, the Florida HBPA and Florida Thoroughbred Breeders and Owners Association have requested the two tracks settle their differences for the sake of the state’s population of horses and horsemen, which risk being over-extended.