Hinny - Physical Description

Physical Description

Hinnies are on average slightly smaller than mules. There is much speculation about the size variances between the two types of hybrids. Some fanciers feel this size difference is merely physiological, due to the smaller size of the donkey dam, as compared with a much larger mare. Others claim it is genetic, but the view of the American Donkey and Mule Society is, "The genetic inheritance of the hinny is exactly the same as the mule."

Thus, hinnies are smaller because donkeys are, for the most part, smaller than horses, and growth potential of equine offspring is influenced by the size of the dam's womb. However, like mules, hinnies do come in many sizes. This is because donkeys come in many sizes, from miniatures, as small as 24 inches (610 mm) at the withers, to Mammoth jacks and jennies that may be over 15 hands (60 inches, 152 cm) at the withers. Thus, a hinny is restricted to being about the size of the largest breed of donkey. Mules, however, have a female horse as a parent, so they can be as large as the size of the tallest breed of horse. There are some very large mules, mostly from work horse breeds such as the Belgian.

Other than size, there are some minor differences that occur frequently between mules and hinnies. The head of a hinny resembles that of a horse, more so than mule heads. Hinnies often have shorter ears, although they are still longer than those of horses, and more horse-like manes and tails than mules. Certain traits, such as the popular gait that some horses and donkeys possess, seem to pass more readily through the male parent. Therefore, many people have tried to produce gaited hybrids by using gaited male horses with female donkeys, in hopes of creating gaited hinnies.