feeding

Laminitis in donkeys compared to horses - Recognition, treatment and prevention

Alexandra K. Thiemann
Presentation date

Laminitis is a relatively common, painful condition of donkeys, ponies and horses. The underlying principles of pathology, diagnosis and treatment are broadly similar, but there are features of donkey anatomy, behaviour and physiology that differ from the horse; understanding these will improve treatment outcomes (Thiemann et al, 2021).

A study of over 2500 donkeys in the UK, found a prevalence of 4% of donkeys presented with laminitis with 46% of cases acute and 54% chronic. This is likely to be an underestimate due to the high levels of obesity and poor detection of the disease.

Recognition of laminitis

Few donkeys in Europe work, most are companion equines. This often results in late detection of laminitis in this species. Typically, signs are subtle, and include altered posture, stiff or shuffling gait and lameness on turning. There may be increased digital pulses and pain to hoof testers. Many donkeys will just lie down, and some owners can misinterpret this as normal resting behaviour.

In chronic cases, there will be abnormal growth rings on the hoof, a flatter sole and, in severe cases upper limb muscle atrophy and flexor tendon breakdown.

Using the Donkey Facial and Donkey Composite pain score (Van Dierendock, et al 2020) enables clinicians to quantify donkey pain and monitor response to treatment and analgesia.

The anatomy of the donkey hoof varies from the horse- P3 sits further distal and there is typically 10mm “founder distance” as normal between the coronary band, and top of the extensor process. The frog tissue is further back on the distal border of P3, this makes use of a heart bar shoe inadvisable. A normal hoof should have at least 10mm sole depth. The external hoof wall is approximately 5° more upright than a horse, but the phalanges, pastern and dorsal hoof wall should align.

Radiographs of donkey hooves need interpreting using donkey parameters.

Obese donkeys suffer from Asinine Metabolic Syndrome (AMS) and donkeys with Body Condition Score >3 (scale 1-5) are at risk. Donkey specific BCS charts and weight nomograms are available (The Donkey Sanctuary, 2020a & 2020b) to assist with assessment. Basal insulin and karo lite testing can be used to confirm a diagnosis of AMS.

Elderly donkeys can develop PPID and, as in the horse, seasonally adjusted donkey specific reference ranges are available.

Treatment of laminitis

As in the horse, the basis of treatment consists of rest, analgesia, foot care and dietary adjustments. In the donkey acute pain and stress, or rapid change in diet may precipitate life- threatening hyperlipaemia (Burden et al, 2011). Ensure the donkey’s appetite and demeanour are closely monitored, and while it is appropriate to reduce the sugar content of any fibre being fed, a reduction in fibre or attempts to diet an obese donkey should be done in a gradual manner.

Donkeys metabolise all NSAIDs (except carprofen) faster than horses, and after a loading dose of 4.4mg/kg BID of phenylbutazone, long term use at 2.2mg/kg BID is considered safe with less risk of dorsal colon ulceration. Meloxicam has a short half- life in donkeys (6 hours) and there is little data on newer NSAIDS. Paracetamol is a useful adjunct at 20-25mg/kg BID. Miniature donkeys require TID dosing for adequate analgesia.

Digital hypothermia is well -tolerated by donkeys and can be useful in acute cases or as preventative in sepsis cases.

In acute cases foot support is best provided with a deep bed, and whole hoof padding or using a commercially available sole support.

Corrective farriery after an episode is an important part of rehabilitation of the hoof, and for chronic cases with flat soles the use of acrylic rim shoes may assist in providing comfort.

Medical support for underlying AMS or PPID is similar to in the horse. The Donkey Sanctuary has little experience yet with the use of levothyroxine to aid weight loss, or insulin lowering drugs such as ertuglifloxin. Pergolide for the reduction of ACTH is known to cause appetite suppression in some donkeys, so when used, the donkey needs careful monitoring.

Prevention of laminitis

Preventative medicine in donkeys is often poor (Barrio et al, 2020), and engaging with owners about correct nutrition, weight management and farrier care is a good strategy. The Donkey sanctuary provides an online resource “The Donkey Academy” with free courses for owners, vets and farriers to assist in this area, as well as fact sheets and handbooks: https://www.thedonkeysanctuary.org.uk/research/what-we-do/knowledge-and-advice/donkey-academy

Donkeys with good dentition cope well on a high fibre, low starch diet where straw provides the bulk of the forage, supplemented by a small amount of vitamin/mineral balancer (Burden et al, 2019). If dieting is needed, suitable mental stimulation helps with prevention of stereotypic behaviour developing (The Donkey Sanctuary, 2020c).

In many cases severe chronic laminitis is undetected and vets and owners can work together to understand the impact of this on Quality of life and End of life Decision-making. The stoic nature of donkeys can results in prolonged unacceptable suffering.

References

1) Thiemann, A. K., Buil, J.and Rickards, K.(2021). A review of laminitis in the donkey. Equine Veterinary Education. 34(10) 553-560. Available from: doi.org/10.1111/eve.13533

2) Van Dierendonck M.C., Burden, F.A. and Rickards, K. (2020). Monitoring acute pain in donkeys with the Equine Utrecht University Scale for Donkeys Composite Pain (EQUUS-DONKEY-COMPASS) and the Equine Utrecht University Scale for Donkey Facial Assessment of Pain (EQUUS-DONKEY-FAP) Animals.10(2) 354. Available from: doi.org/10.3390/ani10020354

3) The Donkey Sanctuary (2020a) Donkey Body Condition Score chart. Available from: https://www.thedonkeysanctuary.org.uk/research/sites/uk/files/2020-01/body-scoring-chart-revised-01-2020.pdf.

4) The Donkey Sanctuary (2020b) Donkey weight nomogram. Available from: https://www.thedonkeysanctuary.org.uk/research/sites/uk/files/2020-01/donkey-weight-estimator-chart-revised-january-2020.pdf

5) Burden, F. A., Du Toit, N., and Hazell-Smith, E. (2011). Hyperlipaemia in a population of aged donkeys: description, prevalence, and potential risk factors. Journal of Veterinary Internal Medicine. 25(6)1420-5.

6) Barrio, E., De Blas Giral, I., Thiemann, A. K. and Vasquez Bringas, F. J. (2020) Demography, preventative health care and reasons for relinquishment of donkeys to an equine charity. Equine Veterinary Journal. 53(2) 324-330. Available from: doi.org/10.1111/evj.13310

7) Burden, F. A. and Bell, N. (2019) Nutrition and Malnutrition of donkeys. Veterinary Clinics of North America Equine Practice 35(3) 469-479.

8) The Donkey Sanctuary (2020c). Environment Enrichment: The Donkey Sanctuary’s Guide to Enriching the Lives of Donkeys and Mules. Available at: https://view.pagetiger.com/EnvironmentalEnrichmentforDonkeys/EnvironmentEnrichmentfordonkeys [Accessed September 19 2020].

Nutrition and dental care of donkeys

The domestic donkey is descended from wild asses and has evolved to live in some of the most inhospitable places on earth. Little research has been carried out to address the specific needs of the donkey, which has traditionally been viewed as a small horse. The donkey is different from the horse in many ways; of particular note is its ability to thrive on highly fibrous feeds. This article discusses the nutritional requirements of donkeys and how dental disease may play a role in determining their nutritional requirements.

Journal
Volume
35
Start page
405
End page
410
Publication date
Country

Donkey nutrition and malnutrition

The domestic donkey is a unique equid species with specific nutritional requirements. This article examines the importance of feeding strategies that mimic the donkey's natural environment using poor nutritional quality fibers and access to browsing materials. The relationship between nutrition and health is examined and practical approaches to the healthy and sick donkey are discussed.

Published online ahead of print.

Volume
35
Issue
3
Start page
469
End page
479
Publication date
Country

Digstible energy requirements of mexican donkeys fed oat straw and maize stover

The limited availability of food, together with the constraints that traditional management systems impose on the natural foraging behaviour of donkeys, often results in severe under-nutrition. Few studies have been conducted into the digestibility of different forages and little information exists on nutritional requirements of donkeys. In order to measure digestible energy requirements of donkeys under tropical conditions, an experiment was carried out at the Centre for Research in Agricultural Science (CICA) and the Faculty of Veterinary Medicine of the Universidad Autónoma del Estado de México located in the Toluca valley, Central México. Thirty-two donkeys of a body condition typical for Central México were divided into four groups of 8 animals each according to their sex and live weight: group 1 (Gl) comprised male donkeys below the average body weight (102 ± 5 kg); group 2 (G2) comprised male donkeys of average body weight (121.5 ± 4 kg); group 3 (G3) comprised female donkeys below average weight (111.8 ± 5 kg); and group 4 (G4) comprised female donkeys of average weight (127.6 ± 5 kg). A diet of oat straw or maize stover and 15% alfalfa hay was offered to meet exact maintenance requirements. The donkeys were monitored for 13 months. The live weight of all animals was recorded daily in order to monitor whether maintenance requirements were being met. Mean daily digestible energy (DE) requirements were measured during the winter, spring, summer and autumn of 2003–2004. Digestible energy requirements of all four sex and liveweight groups were significantly (p > 0.05) higher during the spring than during the other seasons of the year (13.5, 18.0, 10.4 and 14.3 MJ DE per day during winter, spring, summer and autumn, respectively). Predicted DE requirements of donkeys with a live weight range betweenn 90 and 150 kg using the data from the present study were less than those predicted using scaled-down horse feeding standards.

Volume
37
Issue
Supp 1
Start page
123
End page
142
Publication date
Country

Dietary management to improve the gastrointestinal health of the donkey

Faith A. Burden
Nikki Stradling
Presentation date

The Donkey Sanctuary is a welfare organisation which cares for over 2500 donkeys. Donkeys may require additional feeding due to dental disease, ill health or previous neglect. Research in 2005 highlighted that impaction colics (IC) were a significant cause of mortality in resident donkeys (50 cases, 16% of total euthanasias or deaths) and gastric ulceration (GU) was common in donkeys examined post mortem (PM) (41%). Further studies established that feeding practices were contributing to the incidence of IC and GU. Cox et al.1, (2007) demonstrated that donkeys fed concentrate rations were at an increased risk of developing IC (Odds Ratio=2.5, P<0.001). Research in to GU by Burden et al.2, (2009) showed an increased risk of donkeys developing GU when fed cereal concentrate rations (OR=2.4, P<0.001).

Feeding practices were changed from 2008 onwards; prior to this cereal-based rations were fed in meals to donkeys requiring additional feed. They were replaced with fibre-based concentrates fed ad libutum or in small meals. The incidence of GU and IC have been monitored since these changes through PM examination of all animals that die or are euthanased. Prevalence at PM of IC in 2011(5% (n=13)) was significantly lower (P<0.001) than in 2005 (16% (n=50)), univariable logistic regression analysis indicated that donkeys fed concentrate rations are no longer at a greater risk of IC (P>0.05) when compared with those not fed concentrates. Active GU was seen in 7% (n=25) of donkeys at PM in 2011 compared to 41% in 2005, Univariable logistic regression analysis indicated that donkeys fed fibre-based concentrate rations were at no greater risk of developing GU than those not fed concentrates (P>0.05). During this time period the only significant management changes made were those related to feeding; however the effect of other variables on the prevalence of GU and IC at PM warrants further investigation.

Country
Published as conference proceedings

Some factors affecting the digestible energy requirements and dry matter intake of mature donkeys and a comparison with normal husbandry practices

The purpose of this study was to compile practical feeding guidelines for donkeys in the UK. Current guidelines are to feed 0.75 of horse feeding recommendations on a body weight basis. However, the superior digestive efficiency of donkeys, compared to horses, may render the use of horse recommendations inappropriate. The formulation of guidelines specific to donkeys would enable owners to calculate their donkey‟s requirements with greater accuracy and prevent overfeeding.

A postal survey, used to gain information on the body condition score of donkeys in the UK, and the husbandry and feeding practices used to manage them, indicated that approximately 24% of donkeys in the UK are overweight. Feeding practices indicated that although owners were aware of their donkey‟s requirement for fibrous forages, the practice of feeding unnecessary concentrates, chaffs and high energy forages, in addition to grazing, was the likely cause of donkeys becoming overweight. The finding that the majority (85 – 90%) of donkeys were kept as non-working companion animals also reduced the need for owners to feed higher energy foods to their donkeys. Results also suggested that owners were unsure of how to adjust their donkey‟s diet to account for seasonal changes in requirements and pasture availability, as most owners‟ adjusted grazing access, and not the feeding of supplementary feeds.

From a study of dry matter (DM) and digestible energy (DE) intakes by 20 mature donkeys maintaining weight during each UK season, the maintenance DE requirements of donkeys were calculated. Results showed no effect of sex on DM or DE intake. Season significantly (P<0.001) affected DM and DE intakes, implying increased requirements in winter compared to spring, summer and autumn. Dry matter intakes (DMI) increased from 51g/kg BW0.75 in spring, summer and autumn to 66g/kg BW0.75 in winter. Digestible energy requirements increased from 0.32MJ/kg BW0.75 in spring, summer and autumn to 0.43MJ/kg BW0.75 in winter. Comparison of results with horse recommendations showed considerably reduced requirements by donkeys. Horse recommendations overestimated DE requirements in summer and winter by 82 and 30%, respectively, making horse recommendations unsuitable for calculating donkey energy requirements.

Husbandry practices commonly used by owners to manage their donkeys grazing access (grazing time, grazing area, strip grazing), were assessed for their effect on DMI by grazing donkeys in summer and autumn, using n-alkanes. The effect of grazing time was assessed by restricting donkeys to 8, 12 or 23 hours grazing per day. Season significantly affected food intake with donkeys in the 8 and 23 hour grazing groups eating more during summer when pasture availability was greater. Donkeys responded to the poorer quality summer pasture by grazing more intensively but less selectively, increasing the rate at which food was consumed. Grazing time was only influential over grass intake in summer, when pasture was more abundant. Restricting donkeys to 12 hours or less grazing per day significantly (P<0.001) reduced their grass intake compared to that of donkeys with 23 hours access. When grazing sparse pastures (autumn), grazing time did not influence grass intake, indicating an effect of herbage mass on grazing behaviour. Herbage mass was the most influential factor over diet composition (percentage of grass and straw consumed) in a second grazing study assessing the affect of strip grazing and set stocking systems on intake by grazing donkeys during summer and autumn. Herbage mass per donkey was higher in the set stocking system during both seasons, resulting in higher grass intakes. Determining if either grazing system was more effective at regulating grass intake was prevented due to differences in pasture availability between study sites.

It is concluded that donkeys have lower DMI and maintenance DE requirements than horses, requiring donkey feeding guidelines to be formulated. Excess body weight in donkeys is caused in part, by the feeding of energy dense feeds in addition to low energy forages. Most owners place little nutritional importance on pasture, despite its potential to provide a large percentage of daily DM, DE and nutrient intake. Therefore nutritional guidelines must include advice on how to manage access to grazing, and how to feed donkeys with access to pasture. Restricting grazing time to 8 hours a day did reduce grass intake by donkeys, but was only effective when grazing abundant pastures. Providing ad libitum straw to grazing donkeys allows them to satisfy their DM and dietary fibre requirements without consuming excess energy.

Subscribe to feeding