3. small Anim. Pract. (1975)
16, 579-591.
First aid and veterinary treatment of wild birdsX J. E . C O O P E R Baringo, 33 Warrington Road, Harrow, Middlesex
ABSTRACT The first aid and veterinary treatment of wild birds is outlined and attention is drawn to the legal and scientific justifications for such work. Particular emphasis is laid upon the careful examination of such cases and the importance, in subsequent treatment, of good management and nursing. Specific topics discussed include the care of young birds and the treatment of infectious and parasitic diseases, traumatic injuries, poisoning and oiling. INTRODUCTION Large numbers of sick, injured and orphaned wild birds are picked up by the public each year. A number of these find their way to the veterinary surgeon, who is asked for advice on their care and treatment. Few veterinary surgeons are knowledgeable on wild birds. Such lack of expertise is understandable, since the treatment of wild species is usually time-consuming and rarely financially profitable, but it can be argued that some knowledge of the subject may prove advantageous. Whatever the feelings of the veterinary professioo-and there are, alas, many who offer only euthanasia as a solution to wild bird problems-the public are, in general, very concerned about such matters. There must be few households where an attempt has not been made to rear a fledgling bird and many people will devote considerable time and money to the treatment of a sick or injured individual. Such concern is reflected by the number of ‘wild bird hospitals’ which have sprung up all over the country, some of them financed by such organizations as the RSPCA and Wild Bird Hospital Society (WBHS). T h e majority of these hospitals lean heavily on the veterinary profession for guidance and expect
* Presented to 18th Annual Congress BSAVA. London, 579
1975.
580
J , E. COOPER
skilled advice. It is pertinent to note that in their booklet on the treatment of wild birds, the Royal Society for the Protection of Birds (RSPB) states that ‘Diseases or injuries should be treated by a veterinary surgeon as soon as possible’ (Anon, 1972a). Such an attitude is commonplace and it behoves us to consider whether, as a profession, we offer the service expected of us in this field. Much valuable information can be learned from the treatment of wild birds. The subject has been referred to only briefly in scientific texts (see, for example, Petrak, 1969) despite the attention paid to the veterinary treatment of captive birds, ranging from budgerigars to waterfowl. However, wild birds pose a particular challenge since they are almost invariably ‘poor risk’ patients and in the majority of cases need skill and patience in handling, feeding and treatment. Much of scientific or ecological importance has already been learned from wild birds including information on infectious and parasitic diseases and valuable data . on the cleaning and rehabilitation of oiled seabirds. I t would be pertinent to mention the legal position. The majority of the British wild birds are protected by law (The Protection of Birds Act, 1954)’ this stating that it is an offence to ‘kill, injure, or take, or attempt to kill, injure, or take’ such species. However, the Act does permit the taking of a wild bird by a person ‘if he satisfies the court before whom he is charged that the bird had been disabled otherwise than by his act and was taken or to be taken solely for the purpose of tending it and releasing it when no longer disabled’. The euthanasia of wild bird casualties is covered by Section 4(2) (c) which states that a personshall not be found guilty of an offence ‘by reason of the killing of any wild bird if he satisfies the court before whom he is charged that the bird had been so seriously disabled otherwise than by his act that there was no reasonable chance of its recovering’. I t could be argued therefore that the veterinary surgeon who destroys a young, but uninjured, owl brought to his surgery may, in fact, be contravening the law. This is, undoubtedly, a debatable topic but the salient point is that the majority of our native birds are afforded protection under the law and that indiscriminate destruction cannot be justified on either legal or scientific grounds. I n this paper the first aid and veterinary treatment of wild birds is outlined and discussed. TYPES OF PATIENT Wild bird casualties can be conveniently categorized as follows : (1) Youngsters (orphaned) (2) Injured (3) Diseased (infectious and parasitic) (4)Poisoned ( 5 ) Oiled Each of these groups poses its own problems and mention of these will be made.
58 1
TREATMENT OF WILD BIRDS
GENERAL EXAMINATION AND TREATMENT A plan for the examination of wild birds is given in Table 1. As can be seen, euthanasia may be indicated at each stage and factors which will influence whether or not a bird should be killed include: Humanitarian grounds. Is the bird in severe pain or discomfort? Presence of infectious disease. Is there a danger of spread of disease to man or other animals ? Species. Is the bird an agricultural pest, such as a wood pigeon (which can be legally destroyed) or, conversely, is it an uncommon or rare species which warrants particular conservation and protection ? Practical aspects. Care and treatment of a wild bird costs money and time and someone must be willing to spare both. Proposed facilities may not be suitable for treatment. Particularly important are the long-term prospects for the bird; will it finally be able to return to the wild and if not, who will care for it ? Euthanasia will not be discussed in detail. The most humane method for small birds is, probably, intra-peritoneal injection of pentobarbitone sodium (Fig. 1) or the head can be struck against a hard surface. Larger birds can have their necks dislocated as for poultry. Staff of bird hospitals often request guidance on euthanasia and here the veterinary surgeon can play an important part in ensuring that humane techniques are followed. Under certain conditions, a small quantity of pentobarbitone can be supplied but it is generally wiser for laymen to use a non-irritant and non-inflammable inhalation anaesthetic, such as methoxyflurane, or to be instructed in physical methods of destruction. If a wild bird is to be treated, a tentative diagnosis should be made at the initial examination. The bird should be carefully handled and examined. I n many cases the clinical picture will be vague, with non-specific signs of lethargy and depression, and such birds must be managed carefully until a detailed examination is possible. TABLE 1. Treatment of wild birds Initial examination
/ Euthanasia
1 Initial treatment
kih Nursing
Specific examination and treatment
Euthanasia
Retention in captivity
C
Release
582
J . E. C O O P E R
Initial treatment of all wild birds consists of nursing. As was emphasized before, such patients are always ‘poor risk’ and while certain first-aid procedures may be necessary, ambitious attempts at treatment at too early a stage will almost invariably result in disaster. Nursing involves four main factors-warmth, food, fluids and minimum disturbance. Birds have a high metabolic rate and must be maintained at high temperatures; wild bird casualties thrive best a t approximately 75-80°F. Food intake must be maintained, if necessary by force-feeding (see later). The administration of fluids is essential in cases of injury (especially haemorrhage) and enteritis. Glucose saline solution is recommended and its use is similar to that in other animals.
FIG. 1. Intra-peritoneal injection of barbiturate for euthanasia. The picture shows the correct method of handling a small bird, in this case a yellow-hammer (Emberira cilrimlla)
Full examination of a bird must be carried out carefully and thoroughly. Wild species will usually be frightened by handling and fear may be manifested by such features as tachycardia and tachypnoea. Most diurnal birds become calmei. when it is dark and therefore a subdued light or the covering of the eyes of the bird will help facilitate handling. Clinical aids to diagnosis include the stethoscope and the ophthalmoscope. The former is of only limited value but lung and air sac sounds may be detected. The ophthalmoscope will permit testing of the pupillary reflex and examination of intra-ocular structures, particularly blood clots. Certain laboratory tests may also prove of value in some cases. Haematology can be a useful guide to prognosis, lowered PCV values often being associated with blood loss. Anaemia in birds is often manifested by an increase in erythrocytes
T R E A T M E N T OF W I L D BIRDS
583
with basophilic staining to their cytoplasm (see for example, hfarkus & Oosthuizen, 1972), and examination may also reveal blood-born Protozoa or microfilariae. Faeces can be cultured for bacteria and examined parasitologically. FEEDING Birds vary greatly in their dietary requirements. Most young passerine (perching) birds will eat scrambled egg and convalescent diets such as ‘Farex’ and ‘Farlene’ (Glaxo Laboratories Ltd). T h e addition of chopped maggots, worms, meat or
FIG.2. X kestrel (Falco tinnunadus) showing signs of clinical osteodystrophy. The legs are twisted and fractured and there is cloaca1 impaction. The bird had received an all-meat diet.
fruit will aid acceptability by insectivorous and frugivorous species. Later, proprietary diets can be used, such as mixed seed for finches and insectivorous diets for robins, tits and thrushes. Birds of prey are best fed on laboratory mice or day-old chicks: failing these, raw meat can be used but it must be supplemented with bone meal to prevent osteodystrophy (Figs 2-4) and with feather, fur or
584
J. E. COOPER
FIG.3. X-ray of the previous kestrel showing lack of calcification of bones and multiple fractures..
FIG.4.X-ray of a normal kestrel for comparison with Fig. 3.
TREATMENT OF WILD BIRDS
585
cotton wool to facilitate pellet formation. Seabirds should be given chopped fish; and ducks, geese and swans given grain (e.g. wheat) plus commerical poultry (starter) food. Crows and gulls will take most types of animal food, including chopped meat, insects and tinned dog food. Waders need insects, worms and finely minced meat. It should be stressed that bread and milk is not a suitable diet for wild birds of any species although bread and water can be used as an emergency ration for passerines for a short period only. Nor should alcohol, such as brandy, be offered to ailing birds since it can prove dangerous. Many wild birds will not feed voluntarily on arrival and must be force-fed. This technique is not difficult but needs experience and, in the case of those birds with strong bills, some courage! Care must be taken to ensure that the food is pushed over the back of the tongue into the oesophagus and that none enters the trachea. I n some cases it may prove more satisfactory to use a piece of lubricated rubber tubing which is passed down the oesophagus into the crop or stomach. Semiliquid foods can then be squirted or poured down the tubing. A C C O M hIO D A T I O N Small birds can, if necessary, be kept in bird cages but they tend to damage themselves against the bars: this can be reduced by covering three sides of the cage with brown paper or a blanket. The heated ‘hospital cages’ used by aviculturists can prove useful but they are not easy to clean and a bird inside can become overheated. A simple box is preferable and cardboard boxes of various sizes can be adapted to suit a wide range of birds. The box should be lined with newspaper which can be replaced regularly and a perch should be installed for passerine species. Holes must be punched to admit light since the majority of birds cannot feed in the dark. For heating a variety of devices can be used including a hotwater bottle wrapped in a blanket (for recumbent seabirds, for example), an electric heater or a bulb suspended in the cage. The source of heat should be so positioned as to permit the bird to move away from the hot area when necessary. The accommodation of larger birds, such as waterfowl, cannot be discussed in detail. Suffice it to say that for initial treatment large boxes are again often suitable and thereafter thought must be given to the construction of pens in a room or garden shed. SPECIFIC CONDITIONS
Orphaned birds It is important to note that apparently abandoned young birds, whether nestlings or fledglings, are not necessarily ‘orphaned’. I n the majority of cases, if the bird is left alone it will usually be fed by its parents. The veterinary surgeon must therefore be careful to insist that young birds should, whenever possible, be
586
J. E. COOPER
returned to the spot where they were found. Such prompt action will help to ensure the survival of the bird and, at the same time; save the finder the distress of losing his charge, often in the first 24 hours, from cold, hunger or ‘shock’. At times, however, it is necessary to rear a young bird. Feeding and nursing are of paramount importance and were discussed earlier. Every effort should be made to encourage the bird to ‘gape’ for food after which it will usually feed readily. Young birds should be fed every 2-3 hours during daylight but not at night. The care of young birds is covered in a number of books in the lay press (e.g. Engholm, 1970; Knight, 1959) and the veterinary surgeon could refer clients to them. Injuries These are extremely common and whilst external injuries are readily detected, internal damage is frequently difficult to diagnose. The treatment of injuries in wild species is similar to that in cage birds and will not, therefore, be discussed. Generalized infectiom These are not common but usually pose problems of recognition. Since a number of infections are zoonoses, e.g. avian tuberculosis and salmonellosis, rapid diagnosis is advisable. The problems of zoonotic infections in bird hospitals are discussed elsewhere (Cooper, 1973). Avian tuberculosis is fairly common in wild birds but is rarely diagnosed in life. Affected birds are usually thin but frequently retain an appetite. The tuberculin test has been recommended for diagnosis in birds of prey (Stehle, 1965) but the author has not found it of value. Diagnoses have, however, been made on the basis of the finding of acid-fast organisms in faecal smears. I n the case of the wood pigeon (Columba palurnbus), there may be a darker plumage in affected birds (McDiarmid, 1948) and this can prove a useful diagnostic aid. I n general, however, any suspect case of avian tuberculosis should be killed, in view of its known hazard to man (Marks & Birn, 1963). Birds with enteritis pose particular problems. Often the cause is traumatic injury or a change of diet but in some cases bacteria appear to be involved, amongst them the ubiquitous E. coli and, occasionally, Salmonella spp. Bacteriological culture is therefore of value but in the interim therapy can commence with a suitable oral an&-diarrhoea1 agent, especially neomycin. Salmonellosis does not necessarily present with enteritis and should always be considered a potential hazard from wild birds. MacDonald & Cornelius (1969) discuss the disease in free-living species and draw attention to the probable existence of a carrier state. A number of respiratory infections may occur in wild birds. Rhinitis is usually mild and requires no specific treatment. Sinusitis however can on occasion prove fatal. Tylosin or spiramycin are useful in treatment but severe chronic cases may necessitate surgery in. order to remove caseous pus. Lung and air sac infections are
TREATMENT OF WILD BIRDS
587
not easy to distinguish but dyspnoea is probably more pronounced in the former. Tetracyclines are recommended for treatment but in the case of birds of prey, an air-sacculitis, characterized by tachypnoea and regurgitation, responds better to tylosin or spiramycin (Cooper, 1972). An important respiratory disease of wild birds, especially aquatic and raptorial species, is aspergillosis, usually due to Aspergillus fumigatus. Infections commonly supervene following loss of condition or intercurrent disease. Diagnosis is again difficult though a tentative diagnosis based on history may be confirmed by radiography (Ward et al., 1970). Treatment is of doubtful value; success has been claimed with a variety of antifungal drugs by a number of routes but there has rarely been a chance to confirm the diagnosis. Prevention of aspergillosis can be attempted by ensuring that spore counts do not rise too high (by fully ventilating bird rooms, for example) and by making every effort to prevent birds from losing condition too drastically.
Local infections Local abscesses can be opened surgically and the pus removed. Foot infections are a particular problem, especially in raptors and in birds such as auks which usually spend much time on the water but have been confined on solid floored cages for treatment. Foot infections often respond to appropriate antibiotic therapy or irrigation with a quaternary ammonium disinfectant, e.g. cetrimide, but surgery, with careful excision of infected material, may be necessary. Parasitic diseases Parasite burdens increase when wild birds come into captivity and clinical disease may result. Ecto-parasites may be killed with a pyrethrum-based insecticide or a 0.15% solution of the organo-phosphorus compound trichlorphon. Chlorinated hydrocarbon insecticides, such as DDT, BHC and dieldrin can prove toxic and should be avoided. Endo-parasites may also prove troublesome. Piperazine or thiabendazole can be used to treat intestinal nematodes and the latter also kills Syngamus trachea, the gapeworm. If Capillaria worms are present levamisole should be used, either orally or parenterally. Cestodes are probably rarely pathogenic but bunamidine hydrochloride can be used to expel them. Coccidia are often present in the avian alimentary tract and oocysts are frequently detected in faecal samples but as Keymer (1959) points out, they are rarely pathogenic in passerine birds. Coccidiosis is probably most common in gallinaceous birds and columbid (pigeon) species. Sulphadimidine can be used orally to control the parasites but therapy must be accompanied by a high standard of hygiene. Poisoning A number of substances may cause poisoning in wild birds. The clinical signs
588
J. E . COOPER
produced vary but enteritis and nervous signs often predominate. Treatment is usually palliative, with nursing of paramount importance. Nervous signs can be controlled with phenobarbitone or diazepam. If the poison has been ingested the crop or stomach can be washed out with saline. Antidotes and adsorbents can be given orally and A. G. Greenwood (in press) recommends a combination of activated charcoal, kaolin, light magnesium oxide and tannic acid as a general safe antidote. Specific antidotes are available in some cases-for example, atropine for the treatment of organo-phosphate insecticide poisoning-and these should be used when applicable. Oiling This subject has attracted great public interest, particularly following the Torrey Canyon disaster in 1967 when over 10,000 oiled birds were received for treatment by various organizations. The types of oil involved vary but the important point in all cases is that the oil can produce both external and internal effects. External effects are characterized by destruction or reduction of the water-proofing qualities of the plumage. As a result some birds actually drown but the majority suffer from severe heat loss and may finally succumb to the effects of chilling, exhaustion, and starvation. Internal effects are more variable but particularly include enteritis, toxic nephritis and hepatitis. Much research on the pathogenesis and treatment of oiling has been carried out by the Research Unit on the Rehabilitation of Oiled Seabirds at the Department of Zoology, University of Newcastle upon Tyne, which has produced a number ofvaluable reports and papers (Anon, 197213, 1972c, 1973, 1974; Croxall, 1972). Treatment is complex and time-consuming. First, further oil ingestion must be prevented and the bird nursed and treated palliatively. Cleaning itself is usually not performed until the bird is showing signs of improvement in condition. The choice of cleansing agent varies but the Newcastle Unit recommends (1972b) the use of a warm solution of a suitable washing-up liquid followed by rinsing and drying. REHABILITATION The rehabilitation of wild birds is an exceedingly difficult task. The popular image of ‘releasing a bird to the wild’ is a sentimental one. The fact is that the natural mortality rate of wild birds is very high; for example 60430% of birds of prey die in their first year (Brown & Amadon, 1968). As a general rule, the bird that is less efficient at feeding, flying or any other activity than its fellows is likely to die. There are exceptions such as garden species, which may be able to rely on man for food or protection-but the majority must be 100% fit if they are tosurvive. It follows therefore that release of wild bird patients, whatever their history is a
589
TREATMENT OF WILD BIRDS
hazardous business. Those most likely to survive are adult birds which have spent the minimum time receiving treatment. Young birds and those that have received long-term treatment, often with less than perfect results, are at great risk. Various other factors are also important; for example, a bird should always be released in the early morning when it has several hours of daylight in which to feed and establish itself, rather than in the evening. The choice of habitat for release depends upon the species involved but in general it should be one that offers food and shelter. In some cases, e.g. birds of prey and crows, it may be possible to continue to supply food for sometime, thus enabling the bird to adapt itself to the wild slowly. Release of cases is not, strictly, the domain of the veterinary surgeon but he may be asked for a professional opinion as to whether a bird (particularly an uncommon or heavily protected species) is fit enough to be released. Generally it is true to say that if in doubt, a bird should not be released. I t is the author’s view that a wild bird casualty may serve a more useful function in captivity-as a breeding bird, for example-than being released to a n almost certain death in the wild. Opinions vary, however, and the veterinary surgeon must follow his own conscience.
TABLE 2. Dosages of some drugs for wild birds Name Oxytetracycline Chlortetracycline Tylosin Spiramycin
Route Oral In tra-muscular Oral In tra-muscular Oral Intra-muscular Oral In tra-muscular Oral Oral Oral Oral Oral or sub-cutaneous Oral Oral In tra-muscular In tra-muscular In tra-muscular In tra-venous
Sulphadimidine Neomycin Piperazine Thiabendazole Levamisole Bunamidine Phenobarbi tone Diazepam Metomidate Ketamine C T 1341 Glucose saline (5% dextrose, Sub-cu taneous 0.85% saline) Intra-peritoneal
Dose 250 mg/kg bodyweight 15 mgjkg bodyweight 250 mg/kg bodyweight 15 mg/kg bodyweight 200 mg/kg bodyweight 15 mg/kg bodyweigh t 250 mg/kg bodyweight 20 mg/kg bodyweight 500 mg/kg bodyweight 15 mg/kg bodyweight 100 mg/kg bodyweight 500 mg/kg bodyweight 10 mg/kg bodyweight 25 mg/kg bodyweight 30 mg/kg bodyweight 0.25 mg/kg bodyweight 10 mg/kg (approximately) 50 mg/kg (approximately) 10 mg/kg (approximately) 4% of bodyweight 2 % of bodyweight
590
J. E. COOPER
DRUGS The main drugs named in this paper are listed, together with recommended dosages, in Table 2. Contraindicated drugs in wild birds include streptomycin, neomycin, and chlorinated hydrocarbon insecticides. The procaine group is probably toxic to most birds and should only be used in small doses in the larger birds (Cooper, 1972). Parenteral administration of antibiotics appears, clinically, to be preferable to oral and it seems probable that absorption by the latter route is as poor in wild birds as it is in poultry (Smith, 1954). The anaesthetics regularly used by the author are listed in Table 3. Special care must be taken with the anaesthesia of wild birds since although the agents listed are all relatively safe, assessment of depth of anaesthesia is not always easy. TABLE 3. Some recommended anaesthetics for wild birds Local analgesics
Ethyl chloride spray Lignocaine hydrochloride (large species only)
General anaesthetics
(A) Inhalation Methoxyflurane (‘Penthrane’) Halothane (‘Fluothane’) Trichlorethylene (‘Trilene’)
(B) Parmtcral Metornidate (‘Hypnodil’) Ketamine hydrochloride (‘Vetalar’) C T 1341 (‘Saffan’)
For small birds, below 150 g in weight, the author prefers inhalation anaesthetics, especially methoxyflurane. For larger birds intra-venous C T 1341 is ideal for short anaesthesia (Cooper & Frank, 1973) and intra-muscular metomidate or ketamine for longer procedures. CONCLUSIONS The treatment of wild birds is not an easy task and presents a challenge to the veterinary profession. The subject is poorly documented and treatment must be based largely on data from cagebirds and the practical experience of those who handle wild birds frequently. Public concern over wild birds is widespread and while some of it stems from sentimentality, there is increasing evidence of the scientific significance of the treatment of such species.
TREATMENT OF WILD BIRDS
59 1
ACKNOWLEDGMENTS
I am grateful to M r A. Common and Miss P. Ashbolt of the Wild Bird Hospital Society for their co-operation on many occasions, to M r A. G. Greenwood for permission to quote from his unpublished manuscript, to Dr L. Kreel for the X-ray photographs and to my wife for her practical assistance with numerous wild bird patients.
R E F E R E N C ES ANON(1972a) Treatment of Sick and Injured Wild Birds. Royal Society for the Protection of Birds, Sandy, Bedfordshire. ANON(1972b) Recommended Treatment of Oiled Seabirds. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1972~)Second Annual Report, 1971. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1973) Third Annual Report, 1972. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1974) Fourth Annual Report, 1973. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. BROWN,L.H. & AMADON, D. (1968) Eagles, Hawks and Falcons of the World. Country Life Books, Hamlyn House, Middlesex. COOPER, J.E. (1972) Veterinary Aspects of Captive Birds of Prey. The Hawk Trust, Newent, Glos. COOPER, J.E. (1973) Annual Proceedings of the American Association of z o o Veterinariam, 1972 Houston, Texas and 1973, Columbus, Ohio, 28. COOPER, J.E. & FRANK,L. (1973) Vet. Rec. 92, 474. CROXALL, J.P. (1972). Petrol Rev. 26, 362. ENGHOLM, E. (1970) Company of Birds. Neville Spearman, London. A.G. (in press) Poisons. In Cooper, J.E. Ed. Handbook on the First Aid and Care GREENWOOD, of Wild Birds. KEYMER,I.F. (1959) Mod. Vet. Pract. 40, 45. KNIGHT,M. (1959) Taming and Handling Animals. G. Bell and Sons Ltd, London. MCDIARMID, A. (1948) J . comp. Path. 58, 128. MACDONALD, J.W. & CORNELIUS, L.W. (1969) British Birds 62, 28. J. & BIRN,K.J. (1963) Brit. med. J . ii, 1503. MARKS, J.H. (1972). Trans. R. SOC.hop. filed. Hyc. 66, 186. MARKUS, M.B. & OOSTHUIZER, PETRAK,MARGARET L. ( 1 969) Diseases of Cage and Aviary Birds. Lea and Febiger, Philadelphia. SMITH,H.W. (1954) J . comp. Path. 64, 225. STEHLE,S. (1965) Krankheiter bei Greifvogeln (AcciPitres) und bei Eden (Striges) mi& Ausnahme der parasituren Erkrankungen. Inaugural Dissertation Tierarztliche Hochschule, Hannover. WARD,F.P., FAIRCHILD, D.C. & VUICICH, JEANNE V. (1970) Bull. Wildlfe Disease Assoc. 6, 80.
16, 579-591.
First aid and veterinary treatment of wild birdsX J. E . C O O P E R Baringo, 33 Warrington Road, Harrow, Middlesex
ABSTRACT The first aid and veterinary treatment of wild birds is outlined and attention is drawn to the legal and scientific justifications for such work. Particular emphasis is laid upon the careful examination of such cases and the importance, in subsequent treatment, of good management and nursing. Specific topics discussed include the care of young birds and the treatment of infectious and parasitic diseases, traumatic injuries, poisoning and oiling. INTRODUCTION Large numbers of sick, injured and orphaned wild birds are picked up by the public each year. A number of these find their way to the veterinary surgeon, who is asked for advice on their care and treatment. Few veterinary surgeons are knowledgeable on wild birds. Such lack of expertise is understandable, since the treatment of wild species is usually time-consuming and rarely financially profitable, but it can be argued that some knowledge of the subject may prove advantageous. Whatever the feelings of the veterinary professioo-and there are, alas, many who offer only euthanasia as a solution to wild bird problems-the public are, in general, very concerned about such matters. There must be few households where an attempt has not been made to rear a fledgling bird and many people will devote considerable time and money to the treatment of a sick or injured individual. Such concern is reflected by the number of ‘wild bird hospitals’ which have sprung up all over the country, some of them financed by such organizations as the RSPCA and Wild Bird Hospital Society (WBHS). T h e majority of these hospitals lean heavily on the veterinary profession for guidance and expect
* Presented to 18th Annual Congress BSAVA. London, 579
1975.
580
J , E. COOPER
skilled advice. It is pertinent to note that in their booklet on the treatment of wild birds, the Royal Society for the Protection of Birds (RSPB) states that ‘Diseases or injuries should be treated by a veterinary surgeon as soon as possible’ (Anon, 1972a). Such an attitude is commonplace and it behoves us to consider whether, as a profession, we offer the service expected of us in this field. Much valuable information can be learned from the treatment of wild birds. The subject has been referred to only briefly in scientific texts (see, for example, Petrak, 1969) despite the attention paid to the veterinary treatment of captive birds, ranging from budgerigars to waterfowl. However, wild birds pose a particular challenge since they are almost invariably ‘poor risk’ patients and in the majority of cases need skill and patience in handling, feeding and treatment. Much of scientific or ecological importance has already been learned from wild birds including information on infectious and parasitic diseases and valuable data . on the cleaning and rehabilitation of oiled seabirds. I t would be pertinent to mention the legal position. The majority of the British wild birds are protected by law (The Protection of Birds Act, 1954)’ this stating that it is an offence to ‘kill, injure, or take, or attempt to kill, injure, or take’ such species. However, the Act does permit the taking of a wild bird by a person ‘if he satisfies the court before whom he is charged that the bird had been disabled otherwise than by his act and was taken or to be taken solely for the purpose of tending it and releasing it when no longer disabled’. The euthanasia of wild bird casualties is covered by Section 4(2) (c) which states that a personshall not be found guilty of an offence ‘by reason of the killing of any wild bird if he satisfies the court before whom he is charged that the bird had been so seriously disabled otherwise than by his act that there was no reasonable chance of its recovering’. I t could be argued therefore that the veterinary surgeon who destroys a young, but uninjured, owl brought to his surgery may, in fact, be contravening the law. This is, undoubtedly, a debatable topic but the salient point is that the majority of our native birds are afforded protection under the law and that indiscriminate destruction cannot be justified on either legal or scientific grounds. I n this paper the first aid and veterinary treatment of wild birds is outlined and discussed. TYPES OF PATIENT Wild bird casualties can be conveniently categorized as follows : (1) Youngsters (orphaned) (2) Injured (3) Diseased (infectious and parasitic) (4)Poisoned ( 5 ) Oiled Each of these groups poses its own problems and mention of these will be made.
58 1
TREATMENT OF WILD BIRDS
GENERAL EXAMINATION AND TREATMENT A plan for the examination of wild birds is given in Table 1. As can be seen, euthanasia may be indicated at each stage and factors which will influence whether or not a bird should be killed include: Humanitarian grounds. Is the bird in severe pain or discomfort? Presence of infectious disease. Is there a danger of spread of disease to man or other animals ? Species. Is the bird an agricultural pest, such as a wood pigeon (which can be legally destroyed) or, conversely, is it an uncommon or rare species which warrants particular conservation and protection ? Practical aspects. Care and treatment of a wild bird costs money and time and someone must be willing to spare both. Proposed facilities may not be suitable for treatment. Particularly important are the long-term prospects for the bird; will it finally be able to return to the wild and if not, who will care for it ? Euthanasia will not be discussed in detail. The most humane method for small birds is, probably, intra-peritoneal injection of pentobarbitone sodium (Fig. 1) or the head can be struck against a hard surface. Larger birds can have their necks dislocated as for poultry. Staff of bird hospitals often request guidance on euthanasia and here the veterinary surgeon can play an important part in ensuring that humane techniques are followed. Under certain conditions, a small quantity of pentobarbitone can be supplied but it is generally wiser for laymen to use a non-irritant and non-inflammable inhalation anaesthetic, such as methoxyflurane, or to be instructed in physical methods of destruction. If a wild bird is to be treated, a tentative diagnosis should be made at the initial examination. The bird should be carefully handled and examined. I n many cases the clinical picture will be vague, with non-specific signs of lethargy and depression, and such birds must be managed carefully until a detailed examination is possible. TABLE 1. Treatment of wild birds Initial examination
/ Euthanasia
1 Initial treatment
kih Nursing
Specific examination and treatment
Euthanasia
Retention in captivity
C
Release
582
J . E. C O O P E R
Initial treatment of all wild birds consists of nursing. As was emphasized before, such patients are always ‘poor risk’ and while certain first-aid procedures may be necessary, ambitious attempts at treatment at too early a stage will almost invariably result in disaster. Nursing involves four main factors-warmth, food, fluids and minimum disturbance. Birds have a high metabolic rate and must be maintained at high temperatures; wild bird casualties thrive best a t approximately 75-80°F. Food intake must be maintained, if necessary by force-feeding (see later). The administration of fluids is essential in cases of injury (especially haemorrhage) and enteritis. Glucose saline solution is recommended and its use is similar to that in other animals.
FIG. 1. Intra-peritoneal injection of barbiturate for euthanasia. The picture shows the correct method of handling a small bird, in this case a yellow-hammer (Emberira cilrimlla)
Full examination of a bird must be carried out carefully and thoroughly. Wild species will usually be frightened by handling and fear may be manifested by such features as tachycardia and tachypnoea. Most diurnal birds become calmei. when it is dark and therefore a subdued light or the covering of the eyes of the bird will help facilitate handling. Clinical aids to diagnosis include the stethoscope and the ophthalmoscope. The former is of only limited value but lung and air sac sounds may be detected. The ophthalmoscope will permit testing of the pupillary reflex and examination of intra-ocular structures, particularly blood clots. Certain laboratory tests may also prove of value in some cases. Haematology can be a useful guide to prognosis, lowered PCV values often being associated with blood loss. Anaemia in birds is often manifested by an increase in erythrocytes
T R E A T M E N T OF W I L D BIRDS
583
with basophilic staining to their cytoplasm (see for example, hfarkus & Oosthuizen, 1972), and examination may also reveal blood-born Protozoa or microfilariae. Faeces can be cultured for bacteria and examined parasitologically. FEEDING Birds vary greatly in their dietary requirements. Most young passerine (perching) birds will eat scrambled egg and convalescent diets such as ‘Farex’ and ‘Farlene’ (Glaxo Laboratories Ltd). T h e addition of chopped maggots, worms, meat or
FIG.2. X kestrel (Falco tinnunadus) showing signs of clinical osteodystrophy. The legs are twisted and fractured and there is cloaca1 impaction. The bird had received an all-meat diet.
fruit will aid acceptability by insectivorous and frugivorous species. Later, proprietary diets can be used, such as mixed seed for finches and insectivorous diets for robins, tits and thrushes. Birds of prey are best fed on laboratory mice or day-old chicks: failing these, raw meat can be used but it must be supplemented with bone meal to prevent osteodystrophy (Figs 2-4) and with feather, fur or
584
J. E. COOPER
FIG.3. X-ray of the previous kestrel showing lack of calcification of bones and multiple fractures..
FIG.4.X-ray of a normal kestrel for comparison with Fig. 3.
TREATMENT OF WILD BIRDS
585
cotton wool to facilitate pellet formation. Seabirds should be given chopped fish; and ducks, geese and swans given grain (e.g. wheat) plus commerical poultry (starter) food. Crows and gulls will take most types of animal food, including chopped meat, insects and tinned dog food. Waders need insects, worms and finely minced meat. It should be stressed that bread and milk is not a suitable diet for wild birds of any species although bread and water can be used as an emergency ration for passerines for a short period only. Nor should alcohol, such as brandy, be offered to ailing birds since it can prove dangerous. Many wild birds will not feed voluntarily on arrival and must be force-fed. This technique is not difficult but needs experience and, in the case of those birds with strong bills, some courage! Care must be taken to ensure that the food is pushed over the back of the tongue into the oesophagus and that none enters the trachea. I n some cases it may prove more satisfactory to use a piece of lubricated rubber tubing which is passed down the oesophagus into the crop or stomach. Semiliquid foods can then be squirted or poured down the tubing. A C C O M hIO D A T I O N Small birds can, if necessary, be kept in bird cages but they tend to damage themselves against the bars: this can be reduced by covering three sides of the cage with brown paper or a blanket. The heated ‘hospital cages’ used by aviculturists can prove useful but they are not easy to clean and a bird inside can become overheated. A simple box is preferable and cardboard boxes of various sizes can be adapted to suit a wide range of birds. The box should be lined with newspaper which can be replaced regularly and a perch should be installed for passerine species. Holes must be punched to admit light since the majority of birds cannot feed in the dark. For heating a variety of devices can be used including a hotwater bottle wrapped in a blanket (for recumbent seabirds, for example), an electric heater or a bulb suspended in the cage. The source of heat should be so positioned as to permit the bird to move away from the hot area when necessary. The accommodation of larger birds, such as waterfowl, cannot be discussed in detail. Suffice it to say that for initial treatment large boxes are again often suitable and thereafter thought must be given to the construction of pens in a room or garden shed. SPECIFIC CONDITIONS
Orphaned birds It is important to note that apparently abandoned young birds, whether nestlings or fledglings, are not necessarily ‘orphaned’. I n the majority of cases, if the bird is left alone it will usually be fed by its parents. The veterinary surgeon must therefore be careful to insist that young birds should, whenever possible, be
586
J. E. COOPER
returned to the spot where they were found. Such prompt action will help to ensure the survival of the bird and, at the same time; save the finder the distress of losing his charge, often in the first 24 hours, from cold, hunger or ‘shock’. At times, however, it is necessary to rear a young bird. Feeding and nursing are of paramount importance and were discussed earlier. Every effort should be made to encourage the bird to ‘gape’ for food after which it will usually feed readily. Young birds should be fed every 2-3 hours during daylight but not at night. The care of young birds is covered in a number of books in the lay press (e.g. Engholm, 1970; Knight, 1959) and the veterinary surgeon could refer clients to them. Injuries These are extremely common and whilst external injuries are readily detected, internal damage is frequently difficult to diagnose. The treatment of injuries in wild species is similar to that in cage birds and will not, therefore, be discussed. Generalized infectiom These are not common but usually pose problems of recognition. Since a number of infections are zoonoses, e.g. avian tuberculosis and salmonellosis, rapid diagnosis is advisable. The problems of zoonotic infections in bird hospitals are discussed elsewhere (Cooper, 1973). Avian tuberculosis is fairly common in wild birds but is rarely diagnosed in life. Affected birds are usually thin but frequently retain an appetite. The tuberculin test has been recommended for diagnosis in birds of prey (Stehle, 1965) but the author has not found it of value. Diagnoses have, however, been made on the basis of the finding of acid-fast organisms in faecal smears. I n the case of the wood pigeon (Columba palurnbus), there may be a darker plumage in affected birds (McDiarmid, 1948) and this can prove a useful diagnostic aid. I n general, however, any suspect case of avian tuberculosis should be killed, in view of its known hazard to man (Marks & Birn, 1963). Birds with enteritis pose particular problems. Often the cause is traumatic injury or a change of diet but in some cases bacteria appear to be involved, amongst them the ubiquitous E. coli and, occasionally, Salmonella spp. Bacteriological culture is therefore of value but in the interim therapy can commence with a suitable oral an&-diarrhoea1 agent, especially neomycin. Salmonellosis does not necessarily present with enteritis and should always be considered a potential hazard from wild birds. MacDonald & Cornelius (1969) discuss the disease in free-living species and draw attention to the probable existence of a carrier state. A number of respiratory infections may occur in wild birds. Rhinitis is usually mild and requires no specific treatment. Sinusitis however can on occasion prove fatal. Tylosin or spiramycin are useful in treatment but severe chronic cases may necessitate surgery in. order to remove caseous pus. Lung and air sac infections are
TREATMENT OF WILD BIRDS
587
not easy to distinguish but dyspnoea is probably more pronounced in the former. Tetracyclines are recommended for treatment but in the case of birds of prey, an air-sacculitis, characterized by tachypnoea and regurgitation, responds better to tylosin or spiramycin (Cooper, 1972). An important respiratory disease of wild birds, especially aquatic and raptorial species, is aspergillosis, usually due to Aspergillus fumigatus. Infections commonly supervene following loss of condition or intercurrent disease. Diagnosis is again difficult though a tentative diagnosis based on history may be confirmed by radiography (Ward et al., 1970). Treatment is of doubtful value; success has been claimed with a variety of antifungal drugs by a number of routes but there has rarely been a chance to confirm the diagnosis. Prevention of aspergillosis can be attempted by ensuring that spore counts do not rise too high (by fully ventilating bird rooms, for example) and by making every effort to prevent birds from losing condition too drastically.
Local infections Local abscesses can be opened surgically and the pus removed. Foot infections are a particular problem, especially in raptors and in birds such as auks which usually spend much time on the water but have been confined on solid floored cages for treatment. Foot infections often respond to appropriate antibiotic therapy or irrigation with a quaternary ammonium disinfectant, e.g. cetrimide, but surgery, with careful excision of infected material, may be necessary. Parasitic diseases Parasite burdens increase when wild birds come into captivity and clinical disease may result. Ecto-parasites may be killed with a pyrethrum-based insecticide or a 0.15% solution of the organo-phosphorus compound trichlorphon. Chlorinated hydrocarbon insecticides, such as DDT, BHC and dieldrin can prove toxic and should be avoided. Endo-parasites may also prove troublesome. Piperazine or thiabendazole can be used to treat intestinal nematodes and the latter also kills Syngamus trachea, the gapeworm. If Capillaria worms are present levamisole should be used, either orally or parenterally. Cestodes are probably rarely pathogenic but bunamidine hydrochloride can be used to expel them. Coccidia are often present in the avian alimentary tract and oocysts are frequently detected in faecal samples but as Keymer (1959) points out, they are rarely pathogenic in passerine birds. Coccidiosis is probably most common in gallinaceous birds and columbid (pigeon) species. Sulphadimidine can be used orally to control the parasites but therapy must be accompanied by a high standard of hygiene. Poisoning A number of substances may cause poisoning in wild birds. The clinical signs
588
J. E . COOPER
produced vary but enteritis and nervous signs often predominate. Treatment is usually palliative, with nursing of paramount importance. Nervous signs can be controlled with phenobarbitone or diazepam. If the poison has been ingested the crop or stomach can be washed out with saline. Antidotes and adsorbents can be given orally and A. G. Greenwood (in press) recommends a combination of activated charcoal, kaolin, light magnesium oxide and tannic acid as a general safe antidote. Specific antidotes are available in some cases-for example, atropine for the treatment of organo-phosphate insecticide poisoning-and these should be used when applicable. Oiling This subject has attracted great public interest, particularly following the Torrey Canyon disaster in 1967 when over 10,000 oiled birds were received for treatment by various organizations. The types of oil involved vary but the important point in all cases is that the oil can produce both external and internal effects. External effects are characterized by destruction or reduction of the water-proofing qualities of the plumage. As a result some birds actually drown but the majority suffer from severe heat loss and may finally succumb to the effects of chilling, exhaustion, and starvation. Internal effects are more variable but particularly include enteritis, toxic nephritis and hepatitis. Much research on the pathogenesis and treatment of oiling has been carried out by the Research Unit on the Rehabilitation of Oiled Seabirds at the Department of Zoology, University of Newcastle upon Tyne, which has produced a number ofvaluable reports and papers (Anon, 197213, 1972c, 1973, 1974; Croxall, 1972). Treatment is complex and time-consuming. First, further oil ingestion must be prevented and the bird nursed and treated palliatively. Cleaning itself is usually not performed until the bird is showing signs of improvement in condition. The choice of cleansing agent varies but the Newcastle Unit recommends (1972b) the use of a warm solution of a suitable washing-up liquid followed by rinsing and drying. REHABILITATION The rehabilitation of wild birds is an exceedingly difficult task. The popular image of ‘releasing a bird to the wild’ is a sentimental one. The fact is that the natural mortality rate of wild birds is very high; for example 60430% of birds of prey die in their first year (Brown & Amadon, 1968). As a general rule, the bird that is less efficient at feeding, flying or any other activity than its fellows is likely to die. There are exceptions such as garden species, which may be able to rely on man for food or protection-but the majority must be 100% fit if they are tosurvive. It follows therefore that release of wild bird patients, whatever their history is a
589
TREATMENT OF WILD BIRDS
hazardous business. Those most likely to survive are adult birds which have spent the minimum time receiving treatment. Young birds and those that have received long-term treatment, often with less than perfect results, are at great risk. Various other factors are also important; for example, a bird should always be released in the early morning when it has several hours of daylight in which to feed and establish itself, rather than in the evening. The choice of habitat for release depends upon the species involved but in general it should be one that offers food and shelter. In some cases, e.g. birds of prey and crows, it may be possible to continue to supply food for sometime, thus enabling the bird to adapt itself to the wild slowly. Release of cases is not, strictly, the domain of the veterinary surgeon but he may be asked for a professional opinion as to whether a bird (particularly an uncommon or heavily protected species) is fit enough to be released. Generally it is true to say that if in doubt, a bird should not be released. I t is the author’s view that a wild bird casualty may serve a more useful function in captivity-as a breeding bird, for example-than being released to a n almost certain death in the wild. Opinions vary, however, and the veterinary surgeon must follow his own conscience.
TABLE 2. Dosages of some drugs for wild birds Name Oxytetracycline Chlortetracycline Tylosin Spiramycin
Route Oral In tra-muscular Oral In tra-muscular Oral Intra-muscular Oral In tra-muscular Oral Oral Oral Oral Oral or sub-cutaneous Oral Oral In tra-muscular In tra-muscular In tra-muscular In tra-venous
Sulphadimidine Neomycin Piperazine Thiabendazole Levamisole Bunamidine Phenobarbi tone Diazepam Metomidate Ketamine C T 1341 Glucose saline (5% dextrose, Sub-cu taneous 0.85% saline) Intra-peritoneal
Dose 250 mg/kg bodyweight 15 mgjkg bodyweight 250 mg/kg bodyweight 15 mg/kg bodyweight 200 mg/kg bodyweight 15 mg/kg bodyweigh t 250 mg/kg bodyweight 20 mg/kg bodyweight 500 mg/kg bodyweight 15 mg/kg bodyweight 100 mg/kg bodyweight 500 mg/kg bodyweight 10 mg/kg bodyweight 25 mg/kg bodyweight 30 mg/kg bodyweight 0.25 mg/kg bodyweight 10 mg/kg (approximately) 50 mg/kg (approximately) 10 mg/kg (approximately) 4% of bodyweight 2 % of bodyweight
590
J. E. COOPER
DRUGS The main drugs named in this paper are listed, together with recommended dosages, in Table 2. Contraindicated drugs in wild birds include streptomycin, neomycin, and chlorinated hydrocarbon insecticides. The procaine group is probably toxic to most birds and should only be used in small doses in the larger birds (Cooper, 1972). Parenteral administration of antibiotics appears, clinically, to be preferable to oral and it seems probable that absorption by the latter route is as poor in wild birds as it is in poultry (Smith, 1954). The anaesthetics regularly used by the author are listed in Table 3. Special care must be taken with the anaesthesia of wild birds since although the agents listed are all relatively safe, assessment of depth of anaesthesia is not always easy. TABLE 3. Some recommended anaesthetics for wild birds Local analgesics
Ethyl chloride spray Lignocaine hydrochloride (large species only)
General anaesthetics
(A) Inhalation Methoxyflurane (‘Penthrane’) Halothane (‘Fluothane’) Trichlorethylene (‘Trilene’)
(B) Parmtcral Metornidate (‘Hypnodil’) Ketamine hydrochloride (‘Vetalar’) C T 1341 (‘Saffan’)
For small birds, below 150 g in weight, the author prefers inhalation anaesthetics, especially methoxyflurane. For larger birds intra-venous C T 1341 is ideal for short anaesthesia (Cooper & Frank, 1973) and intra-muscular metomidate or ketamine for longer procedures. CONCLUSIONS The treatment of wild birds is not an easy task and presents a challenge to the veterinary profession. The subject is poorly documented and treatment must be based largely on data from cagebirds and the practical experience of those who handle wild birds frequently. Public concern over wild birds is widespread and while some of it stems from sentimentality, there is increasing evidence of the scientific significance of the treatment of such species.
TREATMENT OF WILD BIRDS
59 1
ACKNOWLEDGMENTS
I am grateful to M r A. Common and Miss P. Ashbolt of the Wild Bird Hospital Society for their co-operation on many occasions, to M r A. G. Greenwood for permission to quote from his unpublished manuscript, to Dr L. Kreel for the X-ray photographs and to my wife for her practical assistance with numerous wild bird patients.
R E F E R E N C ES ANON(1972a) Treatment of Sick and Injured Wild Birds. Royal Society for the Protection of Birds, Sandy, Bedfordshire. ANON(1972b) Recommended Treatment of Oiled Seabirds. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1972~)Second Annual Report, 1971. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1973) Third Annual Report, 1972. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. ANON(1974) Fourth Annual Report, 1973. Research Unit on the Rehabilitation of Oiled Seabirds, Dept of Zoology, University of Newcastle upon Tyne. BROWN,L.H. & AMADON, D. (1968) Eagles, Hawks and Falcons of the World. Country Life Books, Hamlyn House, Middlesex. COOPER, J.E. (1972) Veterinary Aspects of Captive Birds of Prey. The Hawk Trust, Newent, Glos. COOPER, J.E. (1973) Annual Proceedings of the American Association of z o o Veterinariam, 1972 Houston, Texas and 1973, Columbus, Ohio, 28. COOPER, J.E. & FRANK,L. (1973) Vet. Rec. 92, 474. CROXALL, J.P. (1972). Petrol Rev. 26, 362. ENGHOLM, E. (1970) Company of Birds. Neville Spearman, London. A.G. (in press) Poisons. In Cooper, J.E. Ed. Handbook on the First Aid and Care GREENWOOD, of Wild Birds. KEYMER,I.F. (1959) Mod. Vet. Pract. 40, 45. KNIGHT,M. (1959) Taming and Handling Animals. G. Bell and Sons Ltd, London. MCDIARMID, A. (1948) J . comp. Path. 58, 128. MACDONALD, J.W. & CORNELIUS, L.W. (1969) British Birds 62, 28. J. & BIRN,K.J. (1963) Brit. med. J . ii, 1503. MARKS, J.H. (1972). Trans. R. SOC.hop. filed. Hyc. 66, 186. MARKUS, M.B. & OOSTHUIZER, PETRAK,MARGARET L. ( 1 969) Diseases of Cage and Aviary Birds. Lea and Febiger, Philadelphia. SMITH,H.W. (1954) J . comp. Path. 64, 225. STEHLE,S. (1965) Krankheiter bei Greifvogeln (AcciPitres) und bei Eden (Striges) mi& Ausnahme der parasituren Erkrankungen. Inaugural Dissertation Tierarztliche Hochschule, Hannover. WARD,F.P., FAIRCHILD, D.C. & VUICICH, JEANNE V. (1970) Bull. Wildlfe Disease Assoc. 6, 80.
