Donkeys mate by a polygynous system, where one dominant male mates with several females. The males do not keep a harem, but do control territories that contain multiple females, as well as subordinate males that are not allowed to mate with the females.
Wild donkeys, known as wild asses, mate during the rainy season in their native desert habitats. Domestic donkeys mate during any season, as do some feral wild donkeys. Their young gestate for about 12 months and are born fully developed. Donkeys generally give birth to one foal that weighs between 19 and 30 pounds. Newborn donkeys can usually stand and nurse within 30 minutes after birth. They nurse for about 5 months before weaning. Both males and females can be sexually mature at about 2 years old, but males are usually not strong enough to control a mating territory until at least 3 or 4 years of age.
Donkeys are capable of mating and producing offspring with horses and zebras, although the offspring are sterile in both cases. The most well-known cross is between a male donkey and a female horse, which produces a mule. The cross between a male horse and a female donkey is known as a hinny.