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,
The Adventures of a Donkey Staples - Jemmy's fifth owner Juba - Donkey who shares Mr Staples' shed with Jemmy and Balaam Earl of Hampton - Jemmy's sixth owner Lady Hampton - Earl of Hampton's wife Lady Harriet - Earl and Lady Hampton's daughter Master Hubert - Lady Harriet's brother Mr Maxwell - Bricklayer; hires Jemmy from Mrs Staples for two months Thomas - Mr Staples' son Cousin Smith - Mr Staples cousin The Sandman - Jemmy's seventh owner Mrs Ellis - Laundress who cares for Jemmy Mr Turner - Jemmy's eighth owner Maria Turner - Mr Turner's eldest daughter Emma Turner - Mr Turner's