Hinny is easier to obtain when the lower chromosome count, the donkey, is in the male. Therefore breeding for hinnies is more hit-and-miss than breeding for mules." The male hinny or mule can and will mate, but the emission is not fertile. Male hinnies and mules are usually castrated to help control their behavior by eliminating their interest in females. Female hinnies and mules are not customarily spayed, and may or may not go through estrus. Female mules have been known, on rare occasions, to produce offspring when mated to a horse or donkey, although this is extremely uncommon. Since 1527,
Now What (horse) the 1952 American Co-Champion Older Female Horse. Now What (horse) Now What (foaled 1937, in Kentucky) was an American Thoroughbred Champion racehorse. Her dam was That's That, and her sire was the 1927 American Horse of the Year and two-time Leading sire in North America, Chance Play. Raced by Alfred G. Vanderbilt II, Now What was trained by Bud Stotler and was a champion at two. As a three-year-old, she finished second in the Molly Brant Handicap, Pimlico Nursery Stakes, and Juvenile Stakes. Now What served as a broodmare for Vanderbilt. Her most successful foal to race was Next Move,