Donkeys and Mules
Table of Contents
- Anatomical Differences Between Horses
- Nutrition and Pasture Management
- Hoof Care
- Genetics and Breeding
- Related Links
There are estimated to be 50 million donkeys (Equus asinus)
and as many mules worldwide. They can be used for such applications
as riding, driving, flock protection, companion, breeding, and training
calves. Donkeys and mules are not small horses. They have anatomical
and physiological differences compared to horses and their care
requires special consideration. Structural differences compared
to horses mean that they require specialized tack and harness for
riding and driving (1).
Jack: Male donkey
Jennet or Jenny (both pronounced the same): Female donkey
Donkey gelding: Castrated male donkey
Mule: The offspring of the mating of a jack with a mare (female
Hinny: The offspring of the mating of a stallion (male horse) with
Mature animals can be further designated into the following classifications
based on height measured at the withers:
Miniature: under 36 inches
Small Standard: from 36.01 to 48 inches
Large Standard: over 48 inches and under 54 inches for females;
over 48 inches and under 56 inches for jacks and geldings
Mammoth: 54 inches or over for females and 56 inches or over for
For more information on registration guidelines, contact the Canadian
Donkey and Mule Association.
Anatomical Differences Between Horses
A number of anatomical differences can challenge the first-time
donkey owner and their veterinarian. Two of these include:
- an obscured jugular furrow (the place where blood samples are
taken or tranquilizers are given). The cutaneous coli muscle is
much thicker than in the horse and hides the middle third of the
jugular vein. It is easier to find the upper third of the jugular.
- The nasolacrimal duct of the donkey is located on the flare
of the nostril rather than the floor of the nostril as it is in
the horse (2).
Donkeys and mules are known to be very stoic animals that are slow
to show pain and discomfort. While these characteristics may be
desirable in many cases, it can lead to problems identifying a sick
The attributes we assign to a donkey being stubborn and having
a lack of intelligence are actually from their natural responses
to new experiences and logical interpretation of a situation. Being
tough animals, they will kick easily and swiftly (2). Donkeys and
mules are very social animals and will benefit tremendously from
the companionship of other animals, such as horses, cattle, sheep
Nutrition and Pasture Management
Donkeys and mules can survive on coarser pastures than a horse.
Lush pastures suitable for horses may be too rich in protein and
energy and, therefore, unsuitable for donkeys. Dry matter intake
of feed as a percentage of body weight should be 1.75%-2.25% to
meet the metabolic demands for maintenance for most donkeys and
mules. Animals that are pregnant, nursing, growing, or used for
heavy work, will have additional feed requirements (rolled oats,
grain, hay or pasture) above their maintenance requirements (1).
Donkeys allowed to graze freely on rich pastures may be prone to
obesity, laminitis (founder) and hyperlipidemia (excess of fat in
the blood). When calculating the energy demands of your donkey,
it is important to know that their body weight cannot be estimated
using a girth weight tape intended for horses. Body condition scoring
of donkeys will also require a different mind set from that used
with horses since donkeys deposit fat somewhat differently than
Donkeys can be alternated with cattle and sheep on pasture. This
management helps maximize pasture usage and reduces the occurrence
of parasites, since the parasites are not generally shared between
species (1,3). Sheep and/or cattle grazing pastures after donkeys
consume the remaining grass along with hatched larvae that have
migrated from stool clumps up to the grass blades. Donkeys commonly
create an area where they can take dust and/or sand baths during
warm weather (4).
Donkeys and mules should always have access to clean water and
a salt. Loose salt is preferred over a salt block since they will
consume a greater volume of loose salt than from a block, especially
in below zero degree temperatures. Most animals will consume anywhere
from 10 to 25 litres of water per day. Snow will not provide these
animals with enough water to meet their needs. Care must be taken
to ensure an unfrozen water supply in ambient temperatures below
Donkeys and mules originated as desert animals and are well adapted
to warmer climates. They can do well in cooler climates, but they
do require shelters or barns in the colder and wet weather. Indoor
housing or run-in sheds are needed during periods of weather extremes,
especially for donkey mares and their foals. The coat of a donkey
does not provide the protection needed and the foals can become
chilled easily. Donkeys tend to grow longer, coarser coats that
lack the protective undercoat that horses have in the winter (4).
Hoof care for donkeys and mules is required every 6-8 weeks. There
are differences in the conformation of the donkey hoof compared
to the horse. In general, the hooves are more upright, tougher,
and more elastic than those of a horse. The bulbs of the donkey
hoof are less developed and the fusion of the bulbs of the heel
is less complete. The heels are naturally long. The pastern angles
are greater than the horse. The frog of the donkey hoof is not meant
to be weight-bearing (5). Overall, mules will have varying degrees
of resemblance to either donkeys or horses (6).
Genetics and Breeding
Horses have 64 chromosomes, while donkeys have 62. When horses
and donkeys are mated, the mule offspring have 63 chromosomes. The
gestation period in donkeys is 12 months on average, but it may
vary from 11 to 14 months. Despite being considered sterile, mare
mules and mare hinnies will have estrus cycles. These cycles can
be regular, or erratic and variable. Female hinnies and mules can
be used as embryo transfer recipients but care must be given to
compatibility of donor and recipient. There have been documented
cases of fertility in the female mule but not the female hinny (7).
A report from Morocco indicates that a mule mare produced a foal
with 62 chromosomes. The cells of the mule mare were a mosaic, some
carrying 63 chromosomes while others carried 62. The foal has 62
and is believed to be fathered by a donkey. This is the fourth female
mule to be confirmed to be fertile (8).
Intact male donkeys and mules can be quite "stallion-like"
or aggressive in behaviour. If they are not being used for breeding
purposes or as a teaser, it is highly recommended that they be castrated.
Castration must be performed by a veterinarian.
Donkeys and mules can also be infested by ectoparasites (skin parasites)
such as flies, lice, ticks, mites and warbles. Refer to Lice
on Horses for further information.
The internal parasites that affect donkeys and mules are typical
for other equid species and, therefore, the recommendations for
control and treatment are those that we use for horses. However,
lungworms are reported to be more common in donkeys than horses.
A comprehensive parasite control program should include pasture
management and environmental sanitation, and regular anthelmintic
wormer administration. Performing routine fecal egg counts will
help to determine the efficacy of treatment and control programs.
Anthelmintics should be chosen conscientiously and their use should
be rotated slowly to decrease the occurrence of resistance. A slow
rotation of wormers is recommended (the same wormer over the course
of a year or more). Your veterinarian can help to determine the
correct parasite control program for you.
The use of horse vaccines for donkeys and mules is necessary because
there are no vaccines specifically developed for them. Protocols
for a vaccination program are usually adapted from those recommended
for horses. The chance of adverse reactions to vaccines are assumed
to be the same as in horses. It is important that donkeys and mules
are vaccinated to aid in controlling the spread of disease.
The above recommendations are intended to introduce basic concepts
of management for your donkey or mule. For more information on donkey,
mule and horse care and management, refer to the
horse secton of the website.
- Svendsen ED. The Professional Handbook of the Donkey. England:
Sovereign Printing Group, 1989.
- Burnham SL. Anatomical differences of the donkey and mule.
Proceedings of the 48th Annual AAEP Convention 2002: 102-109.
- Peregrine A. (2003) Personal communication.
- The Donkey. Alberta Agriculture and Rural Development
- Fowler J. Trimming donkey feet. Equine Veterinary Education
1995; 7: 18-21.
- Jackson J. Naturally shaped hooves. Mules and More 1998; 8
- Taylor TS, Matthews NS, Blanchard TL. Introduction to Donkeys
in the US, Elementary Assology. Texas A&M University College
of Veterinary Medicine
- Kay G. A foal from a mule in Morocco. Vet Record 2003;152 (3):
Donkey and Mule Association
Donkey. Alberta Agriculture and Rural Development