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 Mr Carter and whilst under his care Jemmy falls and breaks his knees. After the accident Mr Carter has no further use for Jemmy and sells him to a Laundress from Kensington named Mrs Dawes. During the care of Mrs Dawes Jemmy see Jenkins break into the yard and try to steal some linen, he is apprehended and transported overseas. After this incident Jemmy meets another donkey named Bobby who knows Balaam. He tells Jemmy that Balaam is ill and Jemmy contemplates escaping to be with him. Jemmy is sent to work for Mr Ford at a fair near Hampstead,