Introduction

Stress is a very real consideration for the avian patient housed in a veterinary hospital and in some cases may contribute to a further decline in health. Wild birds are not familiar with close contact with people, whilst pet birds may find the environment unfamiliar and distressing.

The Veterinary Nurse can play a vital role in reducing anxiety for avian patients. Accurate identification of the species and a basic understanding of its natural biology enable the nurse to provide a conducive environment including appropriate caging, security, nutrition and general nursing care.

Daily records should be maintained whilst the bird is hospitalised. Relevant information will include food intake, urination and defecation, medications and general demeanour. Recording the bird's weight regularly is important as small losses of body weight may rapidly become significant. Initial body weight and subsequent weights provide accurate data to calculate doses and rates for accurate therapeutic delivery.

Heating

Birds fluff their feathers in an attempt to conserve body heat and to trap ambient temperature. Their body temperature is made up of absorbed ambient temperature and metabolic heat. The normal body temperature range in birds is 40°-44°C. Sick birds do not maintain their body temperature, therefore they often look fluffed up. Ambient temperature to house most sick adult birds is 28-33°C. Humidity plays an important role in rehydration and maintenance of water balance in debilitated birds. A relative humidity of 50-70% must be maintained.

By providing a warm environment we take the workload away from the bird and it can concentrate its energy on recovery and healing. In addition to keeping the ambient temperature warm in the room it is often necessary to provide a more direct source of heat positioned over or angled into the cage, a heat globe works well. Place a thermometer in the room to monitor the temperature.

Lighting

Birds do not require any special lighting needs. However all diurnal birds benefit from natural sunlight. It promotes feeding response and is essential for general wellbeing.

Perches

It is essential that the correct size perches be selected for the various species.

 For most species, perches should be made of untreated hardwood. The ideal perch allows the bird to grip without placing pressure on any one part of the foot and avoids the development of sores on the feet. Hard abrasive surfaces such as concrete, Astroturf or hard wood perches may contribute to pododermatitis (bumblefoot) in some species, e.g., water birds and birds of prey. A soft wood, e.g., paperbark or a padded perch is more appropriate for these species. Padding can be achieved by selecting a smaller diameter perch and wrapping it with a towel or bandaging.

 Where space permits, more than one perch should be supplied. One perch should go directly to a feed station. To avoid contamination by faecal droppings perches should not be placed above food and water bowls.

 To reduce excess soiling of perches they should not be placed directly above each other. If natural perches are used, ensure that they are not contaminated with pesticides or chemicals.

 Perches should be stable and not move in the cage, unless the bird is in rehabilitation and requires this type of physical therapy.

Types of Cages

There are many suitable inexpensive cages available. A cage may need some modification depending on the species of bird needing to be housed. Some general suggestions to cover the broad needs of a hospital environment include:

 A good quality hot box, preferably with heat coming from the side or the top, and a thermostat control. A small lined container, e.g., ice cream container, works well to secure small injured birds inside a hotbox.

 Various sized Petpaks work well for larger birds, e.g., ducks, swans and pelicans. This option is suitable if the bird is inactive and not able to perch. A rolled up towel in the shape of a horseshoe aids in keeping the bird upright.

 Standard budgie and cockatoo cages are frequently used. It is recommended that the door in the cockatoo cage is modified to a larger size to facilitate handling.

 Most clinics have solid stainless steel cages. These are good for larger birds, e.g., pelicans and birds of prey.

Some "Do Not's"

 Do not place an exposed cage on the floor with a bird in it. This is very threatening for the bird. Exceptions include stainless steel larger enclosed cages that are located at ground level.

 Do not place the cage in a cat/dog environment. Even if you have covered the cage over the bird will sense predators and will stress.

 Do not keep a cage covered over 24 hours a day. Most birds are diurnal and require some light to stimulate feeding. Cover them over at night for security.

Cage set up needs to be simple. Newspaper is an appropriate substrate for the base of the cage. If the bird is not able to stand or perch, pad the base to reduce trauma to the bird's keel. Avoid placing unnecessary items in the cage as this may hinder your ability to catch the bird efficiently. Wild birds benefit from having foliage to hide amongst for security.

Nutritional Needs

Birds often require supportive nutrition as a part of their care. This may include assisted feeding or crop tubing. Identifying the bird's nutritional needs based on the species and providing the correct diet in appropriate quantity/volume is an essential component of its care plan in the clinic. Very young birds or those with a rapid metabolism, such as nectar feeders, may need to be supplemented soon after they have been examined.

It is useful to keep a variety of commercially prepared diets in your clinic and some ingredients to make up a diet as required. Items such as glucose and commercial mixes (e.g., "Wombaroo" or "Roudybush" varieties) will last for some time if stored correctly. Small fresh amounts of natural foods, e.g., gum nuts, fresh grasses, blossoms should be offered frequently.

It is beyond the scope of this paper to cover all aspects of bird nutrition and techniques for feeding. Suggested references are included below.

Waste Material

You can tell a lot by looking at bird's droppings. Small birds will defecate more regularly than larger birds. Bird faeces has three components: faeces (green/brown, solid/semi-solid), urates (white to creamy white) and urine (clear and watery). The consistency varies with species and will vary according to the bird's diet.

 An important non-invasive observation tool is recognising normal versus abnormal faeces.

 Polyuria and polydipsia are important clinical conditions in birds. It is suggested that birds drink approximately 50ml/kg per day.Polyuria and diarrhoea can be difficult to distinguish from one another.

 Urine should only extend a few mm past droppings. Anything in excess may be polyuria.

 Consider stress-related polyuria.

Endo and Ectoparasites

Many wild birds present with lice, ticks or flat fly. Although ectoparasite burdens are a normal finding in healthy wild birds, an unwell bird may not cope with such a burden and treatment is recommended. Apply powders or sprays sparingly and wear appropriate protective clothing.

Endoparasitic burdens can be very debilitating. A simple faecal flotation and a direct examination test can be performed on fresh faeces or from an oral or cloacal swab to identify parasitic ova and larvae.

Pain in Birds

It is not always easy to identify signs of pain in birds. The following are signs that you should be aware of:

 Less response to humans (particularly in pet birds);

 Picking, feather plucking over painful area;

 Spending additional time on cage floor;

 Increased respiration;

 Increased aggression;

 Abnormal posture, locomotion; and

 Immobile, collapse.

Regardless of identifying signs of pain, analgesia therapy must be implemented if the presenting condition is likely to be painful. Non steroidal anti-inflammatory drugs are used effectively in birds.

Shock

Sick or injured birds will generally present in some degree of shock. There are limitations as to how much nursing a bird can cope with, therefore efficiency and selective care must be considered. Birds do benefit from supportive therapy, including the provision of fluids to increase circulatory volumes, a warm, stress-free environment and non-invasive observation.

Therapeutics in General

Clinical signs of dehydration in birds may be missed by the untrained eye. Assume that a sick/injured bird is a minimum of 10% dehydrated.

Signs include:

 Dull sunken eyes, turgor of eyelid skin;

 Dry and wrinkly skin;

 Turgescence/filling time of the basilic (cutaneous ulnar) vein; and

 Dry mucous membranes.

Hartmann's solution (sodium lactate) is the preferred choice of fluid therapy in birds. Daily maintenance requirement for a bird is approx 50-60ml/kg/day. The volume is based on size, the smaller size birds and juveniles requiring a higher fluid replacement. All fluids being delivered regardless of the route must be warmed to body temperature.

Most common antibiotics used in companion animals are suitable to use in birds. Consideration must be given to the route of delivery and frequency, with advantages to medicating no more than twice a day unless the bird requires supportive feeding frequently and you can medicate a bird at the same time.

Nebulising some drugs is considered an effective delivery method. Most commercially available nebulisers do not break down the pharmaceuticals to particles small enough to penetrate the lower respiratory tract. Particles must be no more than 3 microns to deposit in the lungs and air sacs, 3-7 microns deposit in the trachea and mucosal surface of the nasal cavity. Minimising the dead space volume in the nebulising chamber will also improve the delivery.

Probiotics are being used in many cases now. If the bird requires crop or stomach feeding you may consider making a stock solution of electrolytes with probiotics mixed in and use this stock as your fluid to mix into your choice of feeding formula.

Administering Therapeutics

Air sacs are distributed throughout the body cavity and neck region. To ensure you do not inject directly into an air sac, select a spot where you can visualise a belly of muscle under the skin.

The recommended volume for all intramuscular injections is <0.2ml volume per 100gm of animal. The recommended volume for all subcutaneous injections is 1-3ml volume per 100gm of animal. Unless you are experienced at avian venipuncture you should not consider intravenenous delivery on a conscious bird. Consider a brief mask down to access the vein to reduce stress on the bird.

Aseptic preparation of the injection site requires slightly dampening the feathers to visualise the area. Birds chill quickly and unnecessary wetting of the bird is not recommended. Birds have thin skin, so use the smallest gauge needle whilst allowing the therapeutic to be delivered effectively. Good haemostasis is essential when accessing a vein.

Summary

Avian patients pose a challenge in the hospital environment. They are fragile, difficult to assess and can deteriorate rapidly with few outward signs of illness. A nursing care plan provides a logical approach to work with.

References

1.  Altman R, Clubb S, Dorrestein G, Quensberry K: Avian Medicine and Surgery. W.B.Saunders, 1997.

2.  Forbes & Lawton: Manual of Psittacine Bird. British Small Animal Veterinary Association

3.  Fowler M: Zoo and Wild Animal Medicine Current Therapy 3. W.B. Saunders Company, 1993.

4.  Fowler M: Zoo and Wild Animal Medicine Current Therapy 4. W.B. Saunders Company, 1999.

5.  Hotston Morre A: Manual of Advanced Veterinary Nursing. British Small Animal Veterinary Association

6.  Proceedings 233. Post Graduate Committee in Veterinary Science. Wildlife, The TG Hungerford Refresher Course for Veterinarians: University of Sydney. 1994.

7.  Proceedings 104, Post Graduate Committee in Veterinary Science. Australian Wildlife, The TG Hungerford Refresher Course for Veterinarians: University of Sydney.

8.  Proceedings 36, Post Graduate Committee in Veterinary Science. Fauna, The TG Hungerford Refresher Course for Veterinarians: University of Sydney.

9.  Proceedings 327, Post Graduate Committee in Veterinary Science. Wildlife in Australia, The TG Hungerford Refresher Course for Veterinarians: University of Sydney.

10. Pratt P: Principles and Practices of Veterinary Technology, 1998. Mosby.

11. Rouffignac M, Joy R: A Collaborative Medical and Husbandry Approach to the Conservation of Black Cockatoos in Western Australia. Australian Zookeeping Association Proceedings, 2005.

12. Stocker L: Practical Wildlife Care. 2000. Blackwell Science