BE IN RAPTURES TREATING RAPTORS WITH GUIDE TO USEFUL TECHNIQUES

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1 Vet Times The website for the veterinary profession BE IN RAPTURES TREATING RAPTORS WITH GUIDE TO USEFUL TECHNIQUES Author : JOHN E COOPER, MARGARET E COOPER Categories : Vets Date : June 16, 2008 JOHN E COOPER, MARGARET E COOPER step into the world of birds of prey with details on how to treat these predators effectively BIRDS of prey (raptors) have been kept in captivity for the purpose of falconry for hundreds, possibly thousands, of years. Many species are also displayed in public and private zoological collections. In recent years, increasing numbers of raptors have been maintained for aviculture, scientific research - for sick, injured or orphaned birds - treatment and rehabilitation back to the wild (Cooper, 2002). Birds of prey are commonly considered to be members of the orders Falconiformes (including hawks, falcons and eagles) and Strigiformes (owls) - two different groups of birds that exhibit similar feeding patterns and share certain morphological features. Although much of the biology of both orders of raptors appears comparable, there are significant anatomical and physiological differences that can affect how they are dealt with as patients - for example, falconiform species have a crop, whereas owls do not. The handling and treatment of all birds of prey needs to be properly planned and carried out with sensitivity - not least because of the requirements of the Animal Welfare Act Medical attention for falconiform birds of prey has a long history. Falconry texts, dating back 500 to 1 / 17

2 1,000 years, provide detailed advice on how to recognise certain diseases (Cooper, 2002) and, while many of the treatment methods that were advocated then are outdated, some of the authors recommendations for keeping hawks healthy remain sound. The past 35 years have seen an unprecedented amount of research on both infectious and noninfectious diseases of birds of prey, coupled with the appearance of several authoritative books, many theses and numerous scientific publications (Redig and Ackermann, 2000; Samour, 2008; Lumeij et al, 2000). As a result, raptor medicine is now a discipline in its own right, on a par with other areas of exotic animal veterinary work. Welfare considerations Minimising stressors is an adjunct to examination and treatment. This is important when dealing with casualties, but equally necessary to promote the welfare of any captive or free-living raptor. Reducing stressors starts when the bird is first hospitalised. Any hawk or owl that is regularly disturbed by noise, visual stimuli and the close proximity of humans and other animals can easily become stressed. The bird may also damage itself as a result of its attempts to move away from such stressors. It may be wise, initially, to keep the patient hooded, or in a closed, padded, cardboard box or cupboard, except when feeding or treatment has to be carried out. A balance has to be struck between the wish to reduce stressors and the need for regular monitoring. Handling and restraint Examination of a sick raptor, whether to make a diagnosis or to administer treatment, entails handling and this can easily serve as a stressor, to the detriment of the bird (see Figure 1). Prolonged restraint, in particular, must be carried out proficiently and be limited in duration. Facilities and equipment that are likely to be required, ranging from an examination table to items such as syringes, needles and specimen bottles, must be prepared and put in place before the procedure starts (see Figures 2, 3, 4 and 5). If necessary, the veterinary surgeon should be prepared to terminate or truncate the procedure(s) if the bird is showing signs of distress, such as excessive struggling or hyperpnoea. Making a diagnosis It is important that at least a provisional, but preferably a definitive, diagnosis is made before 2 / 17

3 specific treatment is given to a bird of prey. This may require a full clinical examination, supporting investigations (such as radiography, ultrasonography and endoscopy) and laboratory tests. Even apparently standard procedures, such as the administration of antibiotics, should, whenever possible, follow the taking of a swab and performance of a sensitivity test. At the very least, when infectious disease is suspected, there should be cytological examination of a smear, aspirate or washing to see the sort of organisms that appear to be involved and whether inflammatory or other cells are present. Administration of medicines Treatment methods for birds of prey can conveniently be divided into preventive or therapeutic techniques. Preventive medication for raptors remains limited in scope. Vaccines have been developed and used for certain infectious diseases, such as avian pox. Prophylactic anthelmintics, antibiotics and certain other agents play a role, from time to time, in the face of an outbreak of disease, or when birds are translocated or quarantined. Nutritional supplements probably help to protect birds of prey against certain disorders and immunostimulants may be beneficial. However, little controlled scientific research on this and similar topics has been reported. The value of therapeutic medication in raptors, on the other hand, is increasingly substantiated as a result of properly performed studies. Nevertheless, despite such work, it must be borne in mind that most medicinal agents that are administered to birds of prey are not specifically licensed for them. Therefore, caution must always be exercised in their use and the client made aware of the possible dangers or side effects. Special care needs to be taken with agents that are new on the market. These may appear to have potential for the treatment of raptors, but they have usually not been properly evaluated in such species. Use of a consent form is strongly advocated, whereby the bird s owner signs to confirm that he, or she, understands the situation and accepts the possible risks. Throughout, the requirements of the Veterinary Medicines Regulations and the RCVS Guide to Professional Conduct must be followed, giving particular attention to following the cascade, where there is no suitable authorised veterinary medicine for that particular species. Non-specific therapy, including pain relief This is an integral part of enhancing the welfare of the bird of prey. It includes such important tasks as the administration of fluids and electrolytes, or the palliative treatment of wounds. In contrast to 3 / 17

4 the specific therapy referred to previously, such nonspecific treatment often needs to be carried out at an early stage, especially if the bird s survival or welfare is compromised. For example, stabilisation of an incoming sick raptor should be considered an essential prerequisite to specific medical or surgical treatment. Stabilisation must encompass fluids and electrolytes and can include the administration of corticosteroids (dexamethasone), iron dextran, B-vitamin complex, high calorific enteral preparation and enrofloxacin or another antibiotic (Forbes, 1996). Another important, sometimes essential, part of nonspecific therapy of birds of prey is pain relief. The past few years have seen the appearance, use and testing of a number of efficacious analgesic agents. The correct use of these will not only enhance the welfare of the bird, but also encourage feeding, preening and other important activities that may aid recovery (Cooper, 2002). Nursing One of the key components of supportive therapy for birds - especially (but not exclusively) wild bird casualties - is nursing. This is a practical subject, as much an art as a science. It is often the bird s owner, a wildlife rehabilitator or the veterinary nurse who has the particular skills that make for the successful care of a sick raptor. Our understanding of the value of nursing has advanced greatly in recent years. Nursing can be divided into five main areas: minimising physical, visual and audible stressors (see earlier); metabolic management; carefully formulated administration of analgesics (see earlier); thermoregulation, implying the provision of warmth; and continuous or regular monitoring of the bird. Medication Medicinal compounds can be administered to birds of prey by a variety of techniques: topically (on the skin or into the nares, ears or conjunctival sac - see Figures 6 and 7); orally (in food or by hand); intracloacally; 4 / 17

5 intratracheally; by intramuscular, intravenous, subcutaneous or intraosseous injection; and by nebulisation. Each of the above techniques has its own advantages and drawbacks. Some are more stressful than others. As a general rule, any raptor that needs to be treated should be weighed and given a health check prior to medication. When calculating dosages of medicinal agents, attention has to be paid, not only to the weight (body mass) of the bird of prey, but also to its metabolic rate (MR). As a general rule, the MR of a bird increases as its bodyweight declines. The result is that, in a small raptor, the agent is likely to be absorbed, metabolised and excreted more rapidly than in a larger bird. It is, therefore, good practice not to base dosages on bodyweight alone. Use of allometric scaling (Pokras et al, 1993) permits a more correct calculation of dose and helps to determine how frequently the medicine needs to be administered for optimal effect. Some standard agents appear to be contraindicated or are known to be significantly toxic in raptors (and, sometimes, other avian species). For instance, particular care should be taken with the use of gentamicin, procaine penicillin, amphotericin B, ketoconazole and mebendazole. Other drugs may have local, rather than systemic, effects on the bird - for instance, tetracyclines can cause significant muscle damage when given intramuscularly (Cooper, 2002). Emergencies Emergency medication is an important consideration when working with raptors and, again, it is relevant to welfare. It will be needed, for example, if respiratory or cardiac arrest occurs during anaesthesia. The veterinary surgeon who deals regularly with birds of prey should have an emergency kit to hand and formulate resuscitation protocols for both respiratory and cardiac arrest, for immediate use in the practice. Emergencies are not confined to cases that are undergoing anaesthesia. The problems that are seen frequently in raptors and that warrant urgent attention include low condition and anorexia, respiratory disease with dyspnoea, nervous disorders and life-threatening haemorrhage. Prolonged clinical examination of such birds is often unwise, because of the risk of jeopardising a patient s survival. The critically sick raptor may be treated while conscious but, sometimes, light isoflurane anaesthesia can be beneficial, as it minimises stress during evaluation and therapy. 5 / 17

6 Under such circumstances, anaesthesia must be carried out with caution and with concurrent use of nitrous oxide, if this is available. Non-conventional therapy The correct treatment of a sick raptor can be further complicated by other factors. For example, some falconers, bird-keepers and rehabilitators use or ask their veterinarian for homoeopathic or other nonconventional( complementary and alternative ) medicines. The practitioner may, or may not, agree personally with the use of such therapy and, with the current emphasis in veterinary medicine on employing evidence-based therapy, employing such methods may present practical, ethical and legal dilemmas. For centuries, before the advent of modern therapy, falconers treated their birds with traditional medicines - locally concocted compounds that included herbs and minerals. There are some anecdotal (non-evidence-based) indications that a few of these were efficacious. Some falconers, especially (but not exclusively) in Arabia, still use such traditional medicines to treat their birds, but there are very few cases where any of these substances have been scientifically assessed. In fact, some are known to be dangerous - ammonium chloride is just one example (Samour et al, 1995). Conclusions Despite great advances in recent years, the care of birds of prey continues to present the veterinary surgeon with challenges and dilemmas. The practitioner who treats these valuable and important patients needs to be familiar with the biology and natural history of raptors and know how best to carry out clinical examinations efficiently and humanely. Treatment should be based upon a thorough review of the literature, a scientific but cautious approach to the choice and mode of administration of medicinal agents, and a properly formulated cost-benefit analysis. The words of an Arabic falconry treatise (AD ) are perhaps germane: The recognition of diseases is refined by the observation of symptoms. Do not change the disease through medicines before its recognition and diagnosis... but ascertain and investigate until you understand the disease. As soon as you are firmly convinced of your diagnosis, quickly start the treatment and do not hesitate. 6 / 17

7 References 1. Cooper J E (2002). Birds of Prey: Health and Disease. Blackwell, Oxford. 2. Redig P T and Ackermann J (2000). Raptors. In Tully T N, Lawton M P C and Dorrestein G M (eds), Avian Medicine, Butterworth-Heinemann, Oxford. 3. Samour J H (2008). Avian Medicine. Mosby, London. 4. Lumeij J T, Remple J D, Redig P T, Lierz M and Cooper J E (2000). Raptor Biomedicine III, Zoological Education Network, Lake Worth, USA. 5. Forbes N (1996). Chronic weight loss, vomiting and dysphagia. In Beynon P H, Forbes N A and Harcourt- Brown N H (eds), Manual of Raptors, Pigeons and Waterfowl, BSAVA, Cheltenham. 6. Pokras M, Karas A M, Kirkwood J K and Sedgwick C J (1993). An introduction to allometric scaling and its uses in raptor medicine. In Redig P T, Cooper J E, Remple J D and Hunter D B (eds), Raptor Biomedicine, University of Minnesota Press, USA. 7. Samour J H, Bailey T A and Keymer I F (1995). Use of ammonium chloride in falconry in the Middle East, The Veterinary Record 137: / 17

8 Figure 1. A merlin ( Falco columbarius) is manually restrained for clinical examination. Handling the animal in the pictured manner is stressful and may compromise the bird s welfare. Photos courtesy of MARGARET E COOPER. 8 / 17

9 Figures 2 to 5. Examination and treatment of a chronically injured South American crab hawk ( Buteogallus species ) housed in an outdoor aviary. Figure 2 (above). The examination table is set up in close proximity to, and within sight of, the hawk - but without disturbing it. 9 / 17

Figures 2 to 5. Examination and treatment of a chronically injured South American crab hawk (Buteogallus species) housed in an outdoor aviary. Figure 3 (above).

10 Figures 2 to 5. Examination and treatment of a chronically injured South American crab hawk (Buteogallus species) housed in an outdoor aviary. Figure 3 (above). Items of equipment likely to be needed for the examination are prepared, ready for use. Note, among other things, the hood, gloves and clipboard for notes. 10 / 17

11 Figures 2 to 5. Examination and treatment of a chronically injured South American crab hawk (Buteogallus species) housed in an outdoor aviary. Figure 4 (left). The hawk has been brought over to the table, in preparation for work to begin. 11 / 17

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13 Figures 2 to 5. Examination and treatment of a chronically injured South American crab hawk (Buteogallus species) housed in an outdoor aviary. Figure 5. With the help of an assistant, clinical examination of the hawk commences. 13 / 17

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15 Figure 6 (above). A blood sample for diagnostic haematology is taken from the bird s basilic vein. The bird is gently restrained with a towel, the assistant spreading her fingers like a net to minimise direct pressure on the body cavity. 15 / 17

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17 Figure 7 (right). An ophthalmological preparation is applied to the left eye. Note how the hawk is handled to reduce damage to it or to personnel. 17 / 17 Powered by TCPDF (

ASSESSMENT Theory and knowledge are tested through assignments and examinations.

ASSESSMENT Theory and knowledge are tested through assignments and examinations. Level 2 Diploma for Veterinary Nursing Assistants 600/9504/0 QUALIFICATION PURPOSE The Veterinary Nursing Assistant qualification aims to prepare and support students for a career as a veterinary nursing