Approach to the Dull Donkey

NORMAL BEHAVIOUR

Donkeys often live to advanced ages or in many countries are worked/ overworked to near exhaustion. For these reasons the common perception is that all donkeys tend to look dull or quiet. There can be a lack of appreciation of the normal full range of behaviours that healthy, pain-free donkeys engage in.

Familiarity with the normal behaviour of a donkey allows identification of subtle changes in behaviour and demeanour and earlier awareness of problems.

Young donkeys in particular, should be friendly, inquisitive and playful. Mature donkeys should still engage in behaviours such as mutual grooming, exploring new items and being part of a group.
 

Healthy donkeys will have a good appetite for forage, browsing and treats, and will chew excessively at wooden fences or logs if deprived of fibre.

In response to changes in temperature a healthy donkey will shiver and try to find shelter if cold, and seek shade if too hot.

As befits a herbivore and prey animal, a donkey should spend most of its day (12-20 hours) foraging over wide distances. It may sleep lying down, in short bouts (of approximately 15 minutes for a total of 2-6 hours), and relax standing up for approximately 2-6 hours while another member of its group is on guard.

Studies show that healthy donkeys do exhibit a wide range of behaviours relating to moving, resting, interacting with each other and the environment, and that by being familiar with these the observer can assess and understand when the donkey is in pain or unwell (Regan et al, 2014).

PAIN RELATED BEHAVIOURS

By understanding normal behaviours, it follows that an absence of these behaviours is a clue that the donkey may be in some form of pain or distress. If the owners of a donkey are only used to the behaviours exhibited by small companion animals then there is potential for delayed recognition of serious problems. For example, the prolonged recumbency of a donkey with colic or laminitis is not comparable to the resting behaviour of a dog, and the self-isolation of a sick donkey is not comparable to the normal solitary state preferred by many cats.

Detailed observational studies of working donkeys have shown that using pain relief improved general alertness and inquisitive behaviours and resulted in a higher head position and less restlessness. Donkeys were seen to rest more and show fewer weight shifting behaviours (Regan et al, 2014).

In contrast, when donkeys are overworked and exhausted and showing signs of physical problems they may “shut down”, showing apathy and a very limited range of behaviours. Animals in such a state have severely compromised welfare, although it may not be easily apparent which system is primarily involved.
 

In further studies, clinicians familiar with donkeys were asked to rate pain prior to euthanasia, and this was correlated with the presence of previously ascribed painful lesions at post-mortem examination (Olmos & Burden, 2012). This study found that up to 20% of donkeys were incorrectly identified as not being in pain, and that several subtle behaviours were not being recognised and acted upon by the clinicians.

Some important findings were that donkeys in pain:

• spent more time than controls with lowered head carriage
• had ears that were more static and unresponsive to changes in the environment
• spent up to 30% more time recumbent
• spent up to 40% less time eating.

Pain related behaviours in the donkey can be divided into general and system-specific behaviours.

General pain related behaviours of a dull donkey are to show a reduced normal behavioural repertoire and those found to be relating to pain include symptoms such as:

• general depression
• reduced interactions and self-isolation and a lack of social grooming
• lowered ears, ears that fail to move independently to stimuli, ears often being held horizontally or facing backwards
• lowered head and neck; they may be held below withers’ height
• ineffective (or sham) eating or drinking
• inappetence
• anxiety
• abnormal aggression
• reluctance to move or less general movement.
   

System-specific pain behaviours tend to be less obvious than in horses and ponies.

• Gradual weight shifting can be seen with foot pain.
• While lameness is evident with limb or hoof pain, it is also common for donkeys to lie down more and show reluctance to move.
• With abdominal pain it is more common for donkeys to show inappetence and recumbency rather than rolling and kicking at the abdomen.
   

Research is being directed at improving our ability to detect pain in donkeys using a modified Horse Grimace Scale. Early results appear promising.

CLINICAL EXAMINATION

Analgesia and supportive therapy, including fluids and nutrition, are the most important first-line treatments for a dull donkey. A detailed investigation for a final diagnosis of the problem can follow.

A study on the causes of dullness in a herd of donkeys found that colic and hyperlipaemia accounted for over a third of cases presented. Lameness, liver disease and respiratory disorders were the next most prevalent causes identified. There was a long list of diseases, in all organ systems, that accounted for non-specific dullness in donkeys (Theimann, 2013).

Due to the wide range of conditions that may present with subtle signs when a donkey is ill, a full detailed clinical examination is needed for diagnosis. This should include a rectal examination, a full oral examination with an oral speculum, and a blood sample to check for hyperlipaemia.

If it is not clear which system is involved, then a full blood screen should be run, particularly to assess hepatic and renal function.

The difficulties with carrying out a rectal examination in a small patient can be overcome by the use of good restraint and sedation if necessary. Good lubrication will aid the procedure and spasmolytic medication can be used at the standard equine dose where this is appropriate. In cases where this is really not possible an ultrasound examination of the abdomen may be needed.

Key points in the examination of a dull donkey include:

• observe behaviours including attitude towards food before examining
• check history, including any possible recent stressors in the previous two weeks such as changes in diet, management or loss of companions
• check vaccination status, deworming history and dental care records. Many donkeys have poor, or absent, preventative health programmes
• keep closely-bonded donkeys together for examination and treatment where possible
• be aware of normal donkey-specific physiological parameters
• a full clinical examination should include rectal and oral examination
• respiratory examination may need to include a rebreathing bag due to the non-athletic nature of the donkey
• a lameness examination, including mobility assessment, may be difficult. Donkeys may follow companions more easily than being led.

Geriatric donkeys may have age-related conditions and may be on medication to manage these. It is always challenging in these cases to identify and diagnose new pain-related behaviours or discomfort.
 

The use of objective assessments for quality of life to monitor the aged donkey is a valuable tool in determining when to change medication and management, or to consider euthanasia.

TREATMENT

In many cases the primary cause of dullness or pain may not be readily apparent. The first aim should be to stabilise and support the patient, provide adequate analgesia, and plan to re-examine and perform further tests at an appropriate interval.

Donkeys with depressed appetite, ineffective (‘sham’) eating or anorexia can be assumed to be hyperlipaemic or on the way to becoming so. Fluid and nutritional support is required either by naso-gastric intubation or intravenously where appropriate, for example if ileus is present.

It is good practice to provide this following blood sampling but prior to blood results to avoid delays in treatment.

These patients will also need gastroprotectants as they are at high risk of developing gastric ulceration.

PAIN MANAGEMENT

Analgesia at a dosage and frequency that is appropriate for the donkey should be given. The response to treatment must be evaluated regularly.

• Many of the commonly used Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) will need to be given at a higher dose rate as drugs are metabolised differently in the donkey as compared to that in horses and ponies.
• Adjunct analgesia may be required but there is little or no donkey specific data.
• Use opioids, ketamine, lidocaine, paracetamol at quoted equine dose rates, and monitor the quality of analgesia.
• Fentanyl patches may need changing more frequently in the donkey.
• Local anaesthetic blocks should be used where possible - for example, for dental extractions, castration or lameness.

Many donkeys respond well to good nursing care but this can be complicated where the specific requirements necessary for a donkey may not be available in a hospital.

Improving the mental well-being of the sick donkey is important for recovery:

• keep any companion(s) close by and preferably together
• maintain a calm environment
• allow access to grazing if possible.

PREVENTION

In the majority of cases, donkeys only demonstrate subtle indications of pain or changes in behaviour and may only show obvious signs in the advanced stages of a condition or when suffering severe pain. Therefore, the dull donkey is often an emergency.

If donkey owners learn to regularly assess their donkey’s normal behaviour patterns, they can be quick to respond to any subtle changes indicating dullness.

The regular use of good up-to-date programmes of preventative health care will help reduce the incidence of many problems. Most important are:

• parasite control
• dental examinations and care
• foot care
• weight control
• vaccination.

It cannot always be achieved but care should be taken to reduce stressful situations, and this includes changes to feeding and management. Where possible, changes should be made slowly and the health of the donkey monitored throughout.