Hinny to the action of imprinted genes." A male hinny is properly called a "horse hinny", and a female hinny is properly called a "mare hinny", though in British English both female hinnies and female donkeys are sometimes called "jennets". Hinnies are difficult to obtain because of the differences in the number of chromosomes of the horse and the donkey. A donkey has 62 chromosomes, whereas a horse has 64. Hinnies, being hybrids of those two species, have 63 chromosomes and are sterile. The uneven number of chromosomes results in an incomplete reproductive system. According to the ADMS: "The equine hybrid
Mule the foal was indeed her offspring. A 1939 article in the "Journal of Heredity" describes two offspring of a fertile mare mule named "Old Bec", which was owned at the time by the A&M College of Texas (now Texas A&M University) in the late 1920s. One of the foals was a female, sired by a jack. Unlike its mother, it was sterile. The other, sired by a five-gaited Saddlebred stallion, exhibited no characteristics of any donkey. That horse, a stallion, was bred to several mares, which gave birth to live foals that showed no characteristics of the donkey. In the