Jenny (donkey)
Encyclopedia
A jenny is the term used to describe a female ass
or donkey
. Occasionally, a female mule
is referred to as a jenny, but more often, the term "molly," "mare
" or "mule mare" is used. In western Canada, the term "jennet" is sometimes used instead of "jenny," though the term Jennet
usually refers to a type of horse
popular in the Middle Ages
. One archaic
term for a jenny was "she-ass." An intact male donkey is called a "Jack."
Jennies have a 12 month gestation
period, longer than the 11 month gestation period of the horse mare
. Their actual gestation can range from 11 to 14 months. They also have a conception rate that is lower than the approximately 60-65% rate for mares. Twins are rare, but occur more frequently among donkeys than horses. They have a seasonal estrus (heat) cycle, which, in the Northern Hemisphere
, begins in March and occurs every 21 to 28 days.
A jenny will come back into heat nine to ten days after foaling. However, unlike mares, jennies are usually not bred back on this "foal heat" because their rate of conception is low, probably because the reproductive tract has not returned to normal. Jennies are usually very protective of their foals
, and some will not even come into estrus while they have a foal at side. The time lapse involved in rebreeding, combined with the length of a jennet's gestation, means that a jenny will produce less than one foal per year. Breeders plan for three foals in a four-year period.
Asinus
The subgenus Asinus encompasses four species and several subspecies of Equidae characterized by long ears, a lean, straight-backed build, a scant tail, and a reputation for considerable toughness and endurance....
or donkey
Donkey
The donkey or ass, Equus africanus asinus, is a domesticated member of the Equidae or horse family. The wild ancestor of the donkey is the African Wild Ass, E...
. Occasionally, a female mule
Mule
A mule is the offspring of a male donkey and a female horse. Horses and donkeys are different species, with different numbers of chromosomes. Of the two F1 hybrids between these two species, a mule is easier to obtain than a hinny...
is referred to as a jenny, but more often, the term "molly," "mare
Mare (horse)
A mare is an adult female horse or other equine.In most cases, a mare is a female horse over the age of three, and a filly is a female horse age three and younger. However, in Thoroughbred horse racing, a mare is defined as a female horse more than four years old; in harness racing a mare is a...
" or "mule mare" is used. In western Canada, the term "jennet" is sometimes used instead of "jenny," though the term Jennet
Jennet
A Jennet or Spanish Jennet was a small Spanish horse. It was noted for a smooth naturally ambling gait, compact and well-muscled build, and a good disposition...
usually refers to a type of horse
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
popular in the Middle Ages
Horses in the Middle Ages
Horses in the Middle Ages differed in size, build and breed from the modern horse, and were, on average, smaller. They were also more central to society than their modern counterparts, being essential for war, agriculture, and transport....
. One archaic
Archaism
In language, an archaism is the use of a form of speech or writing that is no longer current. This can either be done deliberately or as part of a specific jargon or formula...
term for a jenny was "she-ass." An intact male donkey is called a "Jack."
Jennies have a 12 month gestation
Gestation
Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during pregnancy can have one or more gestations at the same time ....
period, longer than the 11 month gestation period of the horse mare
Mare
Female horses are called mares.Mare is the Latin word for "sea".The word may also refer to:-People:* Ahmed Marzooq, also known as Mare, a footballer and Secretary General of Maldives Olympic Committee* Mare Winningham, American actress and singer...
. Their actual gestation can range from 11 to 14 months. They also have a conception rate that is lower than the approximately 60-65% rate for mares. Twins are rare, but occur more frequently among donkeys than horses. They have a seasonal estrus (heat) cycle, which, in the Northern Hemisphere
Northern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...
, begins in March and occurs every 21 to 28 days.
A jenny will come back into heat nine to ten days after foaling. However, unlike mares, jennies are usually not bred back on this "foal heat" because their rate of conception is low, probably because the reproductive tract has not returned to normal. Jennies are usually very protective of their foals
Foal
A foal is an equine, particularly a horse, that is one year old or younger. More specific terms are colt for a male foal and filly for a female foal, but these terms are used until the horse is age three or four. When the foal is nursing from its dam , it may also be called a suckling...
, and some will not even come into estrus while they have a foal at side. The time lapse involved in rebreeding, combined with the length of a jennet's gestation, means that a jenny will produce less than one foal per year. Breeders plan for three foals in a four-year period.
Sources
- http://www.springerlink.com/content/y5377tn46k45h3t2/
- http://www3.interscience.wiley.com/journal/121506577/abstract?CRETRY=1&SRETRY=0