Management recommendations for donkeys and mules

Introduction

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^{footnote 1[1]}).

Terminology

• 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 horse)
• Hinny: the offspring of the mating of a stallion (male horse) with a jennet

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 male

For more information on registration guidelines, contact the Canadian Donkey and Mule Association.

Anatomical differences between horses and donkeys

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^{footnote 2[2]}.

Behaviour

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 animal.

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^{footnote 2[2]}. Donkeys and mules are very social animals and will benefit tremendously from the companionship of other animals, such as horses, cattle, sheep or goats.

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^{footnote 1[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 horses.

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^{footnote 1[1]footnote 3[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^{footnote 4[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 0°C.

Shelter

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^{footnote 4[4]}.

Hoof care

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^{footnote 5[5]}. Overall, mules will have varying degrees of resemblance to either donkeys or horses^{footnote 6[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^{footnote 7[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^{footnote 8[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.

Parasites

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.

Vaccination

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.

Summary

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 section of the website.