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Mule

In its common modern meaning, a mule is the offspring of a male donkey and a female horse. This can be compared with the offspring of a male horse with a female donkey, called a hinny. The term "mule" was formerly applied to the offspring of any two creatures of different species – in modern usage, a "hybrid". The mule, easier to breed and usually larger in size than a hinny, has monopolised the attention of breeders. The chromosome match-up more often occurs when the jack (male donkey) is the sire and the mare (female horse) is the dam. Mules and hinnies are almost always sterile.

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