The main cause of the sterility of mules and hinnies is probably related to failure of pairing of homologous chromosomes at meiosis during
Mules can be either male or female, but, because of the odd number of chromosomes, they can't reproduce. However, a male mule should be gelded in order to make him a safe and sociable animal. Except for the long ears, mules look very similar to horses, but their muscle composition is different.
Those mismatched chromosomes make it hard to make viable sperm and eggs. So mules are sterile because horse and donkey chromosomes are just too different. But they are alive because horse and donkey chromosomes are similar enough to mate.
But while mules have turned out to be extremely valuable work animals, neither mules nor hinnies can mate among themselves to produce their own offspring because of their odd origins.
When a female horse meets a male donkey, the pitter-patter of little mule hooves often follows. Yet the offspring have an odd number of chromosomes, which nearly always means that they are sterile and can't reproduce.
Moreover, male ligers have lowered testosterone levels and sperm counts, rendering them infertile while females, though capable of reproducing with either a lion or a tiger, often give birth to sickly cubs that don?t survive.
Hinnies are less popular because people think they have bad attitudes, and it can be more difficult for a jenny to conceive and give birth. Donkeys also tend to have longer gestation periods than horses, and the size of the stallion is important for the health and safety of the jenny (and the foal).
A zorse is the offspring of a zebra stallion and a horse mare. This cross is also called a zebrose, zebrula, zebrule, or zebra mule. The rarer reverse pairing is sometimes called a hebra, horsebra, zebrinny, or zebra hinny. Like most other animal hybrids, the zorse is sterile.
Sex: Male is a 'horse mule' (also known as a 'john' or 'jack'). Female is a 'mare mule' (also known as a 'molly'). Young: A 'colt' (male) or 'filly' (female).
A hinny is the offspring of a male horse and a female donkey, while a mule is the offspring of a female horse and a male donkey.
As in men with DS, puberty appears to be normal in women with DS and starts at the same average age as in the healthy population. Women with DS are fertile, since many cases of maternity have been reported [29].
Mules - when a donkey and horse mate
Mules are the offspring of a male donkey (jack) and a female horse (mare).
As with other hybrid animals, including both Zonkeys and Mules, Zorses are sterile, meaning that although they still display normal breeding behavior, they are unable to produce offspring of their own.
A mule has 63 chromosomes, intermediate between the 64 of the horse and the 62 of the donkey. Mules are usually infertile for this reason. Pregnancy is rare, but can occasionally occur naturally, as well as through embryo transfer. A few mare mules have produced offspring when mated with a horse or donkey stallion.
Mules are a hybrid of a mare (female horse) and a male donkey, but a mule is more intelligent than either. This has been tested scientifically and shown. It is also an example of something called “hybrid vigor.” More on this below.
Mules have inherited the best qualities of both, being larger and faster-moving than donkeys but less picky about food and stabling than horses, and cheaper to keep. They will pull a cart or carry packs across their backs, and can be ridden.
Due to their parents' different numbers of chromosomes male mules are considered sterile and as such they have no reproductive potential. For these reasons it is always advisable to castrate male mules, and where practical to do it as young as possible.
Mules can live up to 50 years, with an average lifespan of 30-40 years.
A jackass is just a male donkey.
This derives from the male donkey's nickname "jack" paired with the original donkey terminology "ass." Female donkeys are called "jennies" or "jennets," but a female ready to breed is known as a "broodmare."
Breeding: A donkey bred to a donkey produces a donkey. Donkey jacks are crossed on horse mares to produce mules, while the opposite cross (stallion x donkey jennet) gives a hinny. There are few pure breeds of donkey in the United States, where they are known by their sizes and types.
Zebras backs aren't evolved to allow a human to ride a long, let alone to carry cargo or even saddle them. so, even if zebras were the nicest animals on the planet, we'd just cause them pain by riding them. This is not to say that there is no such thing as a tame zebra, just that they are not a domesticated species.
“A zonkey is a cross between a zebra and a donkey. Donkeys are closely related to zebras and both animals belong to the horse family. Zonkeys are very rare”.
Most documented cases of mules/hinnies being fertile have been in the female mule (molly/mare mule). A majority of male mules/hinnies are castrated, but one case of a fertile hinny producing live, mature spermatozoa was documented at Texas A&M in the 1950s. Also, mare mules have been used successfully as recipients.
Mules are sterile but female mules are known to produce milk.
A Jenny is a female donkey. A Mule is the offspring from a female horse and a male donkey. A Hinny is the offspring of a male horse and a female donkey. So a mare and a jack make a mule. A stallion and a jenny make a hinny.